Document:

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                                                                     EXHIBIT 4.5
                               PURCHASE AGREEMENT

         This PURCHASE AGREEMENT (this "Agreement"), dated as of March 6, 2002,
is entered into by and between Trinity Industries, Inc., a Delaware corporation
(the "Company"), and Acqua Wellington Private Placement Fund, Ltd., a company
organized under the laws of the Commonwealth of the Bahamas (the "Purchaser"),
for the purchase and sale of shares of the common stock, par value $1.00 per
share (the "Common Stock"), of the Company by the Purchaser, in the manner, and
upon the terms, provisions and conditions set forth in this Agreement.

         WHEREAS, the parties desire that, upon the terms and subject to the
conditions contained herein, the Company shall issue and sell to the Purchaser
and Purchaser shall purchase shares of the Common Stock; and

         WHEREAS, such purchase and sale will be made in reliance upon the
provisions of Section 4(2) or Regulation S ("Regulation S") of the United States
Securities Act of 1933, as amended and regulations promulgated thereunder (the
"Securities Act"), and/or upon such other exemption(s) from the registration
requirements of the Securities Act as may be available with respect to any or
all of the purchases of Common Stock to be made hereunder.

         NOW, THEREFORE, in consideration of the representations, warranties and
agreements contained herein and other good and valuable consideration, the
receipt and legal adequacy of which is hereby acknowledged by the parties, the
Company and the Purchaser hereby agree as follows:

         1. PURCHASE PRICE.

                  (a) Upon the following terms and subject to the conditions
contained herein, the Purchaser hereby agrees to purchase 620,000 shares of the
Company's Common Stock from the treasury of the Company (the "Shares") at a per
share price of $21.00 and for an aggregate purchase price of $13,020,000 (the
"Purchase Price").

                  (b) The Company has authorized and has reserved and covenants
to continue to reserve, free of preemptive rights and other similar contractual
rights of stockholders, a sufficient number of its authorized but unissued
shares of its Common Stock, to effect the issuance of the Shares.

                  (c) The closing (the "Closing") under this Agreement shall
take place at the offices of the Jenkens & Gilchrist Parker Chapin LLP, The
Chrysler Building, 405 Lexington Avenue, New York, New York 10174 at 1:00 p.m.
(eastern time) upon the satisfaction of each of the conditions set forth in
Section 4 hereof (the "Closing Date").

                  (d) The Company shall deliver to the Purchaser on or prior to
the Closing Date a certificate representing the Shares. Upon receipt of the
certificate representing the Shares,

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the Purchaser shall pay the Purchase Price therefor by check, wire transfer or
such other form of payment as shall be mutually agreed upon by the Company and
the Purchaser.

         2. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PURCHASER. The
Purchaser represents and warrants to the Company, and covenants for the benefit
of the Company, as follows:

                  (a) This Agreement has been duly authorized, validly executed
and delivered by the Purchaser and is a valid and binding agreement and
obligation of the Purchaser enforceable against the Purchaser in accordance with
its terms, subject to limitations on enforcement by general principles of equity
and by bankruptcy or other laws affecting the enforcement of creditors' rights
generally, and the Purchaser has full power and authority to execute and deliver
this Agreement and the other agreements and documents contemplated hereby and to
perform its obligations as provided hereunder and thereunder.

                  (b) The Purchaser has received and carefully reviewed copies
of the Public Documents (as hereinafter defined) and has access to the
Commission Documents (as hereinafter defined). The Purchaser understands that no
federal, state, local or foreign governmental body or regulatory authority has
made any finding or determination relating to the fairness of an investment in
any of the Shares and that no federal, state, local or foreign governmental body
or regulatory authority has recommended or endorsed, or will recommend or
endorse, any investment in any of the Shares. The Purchaser, in making the
decision to purchase the Shares, has relied upon independent investigation made
by it and its advisors, if any, and has not relied on any information or
representations made by third parties or by the Company or its officers,
directors, employees, agents, accountants or attorneys. The Purchaser and its
advisors, if any, have been furnished with all materials relating to the
business, finances and operations of the Company and materials relating to the
offer and sale of the Shares which have been requested by the Purchaser. The
Purchaser and its advisors, if any, have been afforded the opportunity to ask
questions of the Company. The Purchaser has sought such accounting, legal and
tax advice as it has considered necessary to make an informed investment
decision with respect to its acquisition of the Shares. The Purchaser
understands that it (and not the Company) shall be responsible for its own tax
liabilities that may arise as a result of this investment or the transactions
contemplated by this Agreement.

                  (c) The Purchaser understands that the Shares are being
offered and sold to it in reliance on specific provisions of federal and state
securities laws and that the Company is relying upon the truth and accuracy of
the representations, warranties, agreements, acknowledgments and understandings
of the Purchaser set forth herein for purposes of qualifying for exemptions from
registration under the Securities Act, and applicable state securities laws.

                  (d) The Purchaser is, and at all times relevant to the offer
to sell the Shares was, an "accredited investor" as defined under Rule 501 of
Regulation D promulgated under the Securities Act.

                  (e) The Purchaser is and will be acquiring the Shares for such
Purchaser's own account, for investment, and not with a view to any resale or
distribution of the Shares in

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whole or in part, in violation of the Securities Act or any applicable
securities laws. The Purchaser is not a "U.S. person" within the meaning of
Regulation S under the Securities Act and the Purchaser has executed this
Agreement outside the United States within the meaning of Regulation S under the
Securities Act. To the extent that the instrument representing the Shares is
registered in the name of the Purchaser's nominee, the Purchaser confirms that
such nominee is acting as custodian for the Purchaser of the securities
represented thereby.

                  (f) The offer and sale of the Shares is intended to be exempt
from registration under the Securities Act. The Purchaser understands that the
Shares purchased hereunder have not been, and may never be, registered under the
Securities Act and that none of the Shares can be sold or transferred unless
they are first registered under the Securities Act and such state and other
securities laws as may be applicable or, in the opinion of counsel reasonably
acceptable to the Company, an exemption from registration under the Securities
Act is available (and then the Shares may be sold or transferred only in
compliance with such exemption and all applicable state and other securities
laws to the reasonable satisfaction of counsel for the Company). The Purchaser
will not sell any of the Shares in violation of this Section 2(f).

                  (g) The Purchaser (i) has such knowledge and experience in
financial and business matters as to be capable of evaluating the merits and
risks of an investment in the Company; and (ii) recognizes that such Purchaser's
investment in the Company involves a high degree of risk.

                  (h) The Purchaser is capable of evaluating the risks and
merits of an investment in the Shares by virtue of its experience as an investor
and its knowledge, experience, and sophistication in financial and business
matters and such Purchaser is capable of bearing the entire loss of its
investment in the Shares.

                  (i) The Purchaser is neither a registered broker-dealer nor an
affiliate of a registered broker-dealer.

                  (j) Neither the Purchaser nor any of its affiliates, officers
or agents will solicit any material non-public information from the Company.

                  (k) The Purchaser has no agreement or arrangement with the
Company or with any third party for the sale or disposition of the Common Stock
to be purchased pursuant to this Agreement.

                  (l) The Purchaser covenants with the Company as follows: The
Purchaser's trading and distribution activities with respect to the Shares will
be in compliance with all applicable state and federal securities laws, rules
and regulations (including, without limitation, regulation M promulgated under
the Securities Act) and the rules and regulations of the New York Stock
Exchange. Neither the Purchaser nor any of its affiliates (as that term is
defined in Rule 405 promulgated under the Securities Act) has taken, nor will
any of them take, directly or indirectly, any action designed to cause or that
would result in, or which constitutes or that might reasonably be expected to
constitute, the stabilization or manipulation of the price of the Common Stock
to facilitate the purchase, sale or resale of the Common Stock or the Shares.

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                  (m) The Purchaser is a company duly organized, validly
existing and in good standing under the laws of the Commonwealth of the Bahamas.

                  (n) The execution and delivery of this Agreement and the
Registration Rights Agreement, the acquisition of any of the Shares and the
consummation of the transactions contemplated by this Agreement and the
Registration Rights Agreement by the Purchaser, will not (i) conflict with or
result in a breach of or a default under any of the terms or provisions of
Purchaser's organizational documents, or (ii) result in a violation of any
material provision of any law, statute, rule, regulation, or any existing
applicable decree, judgment or order by any court, federal or state regulatory
body, administrative agency, or other governmental body having jurisdiction over
the Purchaser.

         3. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY. The
Company represents and warrants to the Purchaser, and covenants for the benefit
of the Purchaser, as of the date of this Agreement, that except as set forth in
the disclosure schedule of even date hereof delivered to Purchaser by the
Company (the "Disclosure Schedule"), which exceptions shall be deemed to be a
part of and to qualify the representations and warranties to which they refer as
if made hereunder:

                  (a) The Company has been duly incorporated and is validly
existing and in good standing under the laws of the state of Delaware, with full
corporate power and authority to own, lease and operate its properties and to
conduct its business as currently conducted, and is duly registered and
qualified to conduct its business and is in good standing in each jurisdiction
or place where the nature of its properties or the conduct of its business
requires such registration or qualification, except where the failure to
register or qualify would not have a Material Adverse Effect. For purposes of
this Agreement, "Material Adverse Effect" shall mean any effect on the business,
prospects, operations, properties or financial condition of the Company that is
material and adverse to the Company and its subsidiaries, taken as a whole.

                  (b) The Company has furnished the Purchaser with copies of the
Company's most recent Annual Report on Form 10-K for fiscal year ended March 31,
2001 (the "Form 10-K") filed with the Securities and Exchange Commission (the
"Commission") and its Form 10-Q for the quarterly period ended September 30,
2001 as amended by its Form 10-Q/A filed with the Commission on November 21,
2001 (the "Form 10-Q" and its current reports on Form 8-K filed on the following
dates: August 1, 2001, August 16, 2001, September 18, 2001 and October 29, 2001
(as amended by its Form 8-K/A filed on December 28, 2001) (collectively, the
"Form 8-Ks," and together with the Form 10-K and the Form 10-Q, the "Public
Documents"). The Public Documents at the time of their filing did not include
any untrue statement of a material fact or omit to state any material fact
necessary in order to make the statements contained therein, in light of the
circumstances under which they were made, not misleading. As used herein,
"Commission Documents" means all reports, schedules, forms, statements and other
documents filed by the Company with the Commission pursuant to the reporting
requirements of the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), including material filed pursuant to Section 13(a) or 15(d) of the
Exchange Act.

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                  (c) The Shares have been duly authorized by all necessary
corporate action and, when paid for by the Purchaser and issued in accordance
with the terms hereof, the Shares shall be validly issued, will be fully paid
and non-assessable.

                  (d) Each of this Agreement and the Registration Rights
Agreement attached hereto as Exhibit A (the "Registration Rights Agreement") has
been duly authorized, validly executed and delivered on behalf of the Company
and is a valid and binding agreement and obligation of the Company enforceable
against the Company in accordance with its terms, subject to limitations on
enforcement by general principles of equity and by bankruptcy or other laws
affecting the enforcement of creditors' rights generally, and the Company has
full power and authority to execute and deliver this Agreement and the other
agreements and documents contemplated hereby and to perform its obligations
hereunder and thereunder.

                  (e) The execution and delivery of this Agreement and the
Registration Rights Agreement, the issuance of any of the Shares and the
consummation of the transactions contemplated by this Agreement and the
Registration Rights Agreement by the Company, will not (i) conflict with or
result in a breach of or a default under any of the terms or provisions of, (A)
the Company's certificate of incorporation or by-laws, or (B) of any provision
of any material indenture, mortgage, deed of trust or other material agreement
or instrument to which the Company is a party or by which it or any of its
material properties or assets is bound, (ii) result in a violation of any
material provision of any law, statute, rule, regulation, or any existing
applicable decree, judgment or order by any court, federal or state regulatory
body, administrative agency, or other governmental body having jurisdiction over
the Company, or any of its material properties or assets or (iii) result in the
creation or imposition of any material lien, charge or encumbrance upon any
material property or assets of the Company or any of its subsidiaries pursuant
to the terms of any agreement or instrument to which any of them is a party or
by which any of them may be bound or to which any of their property or any of
them is subject except in the case of clauses (i)(B) or (iii) for any such
conflicts, breaches, or defaults or any liens, charges, or encumbrances which
would not have a Material Adverse Effect.

                  (f) The sale and issuance of the Shares in accordance with the
terms and on the basis of the representations and warranties set forth in this
Agreement will be exempt from the registration requirements of the Securities
Act.

                  (g) No consent, approval or authorization of or designation,
declaration or filing with any governmental authority on the part of the Company
is required in connection with the valid execution and delivery of this
Agreement or the offer, sale or issuance of the Shares or the consummation of
any other transaction contemplated by this Agreement (other than any filings
which may be required to be made by the Company with the Commission, or New York
Stock Exchange or pursuant to any state or "blue sky" securities laws, and, any
registration statement which have been made or may be filed pursuant to this
Agreement).

                  (h) There is no action, suit, claim or proceeding before or by
any court or governmental agency or body, domestic or foreign, now pending
against or affecting the Company, or any of its properties, which questions the
validity of this Agreement, the Registration Rights Agreement or the
transactions contemplated thereby or any action taken or to

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be take pursuant thereto. Except as described in the Public Documents, there is
no action, suit, claim or proceeding before or by any court or governmental
agency or body, domestic or foreign, now pending against or affecting the
Company, or any of its properties, which, if adversely determined, is reasonably
likely to result in a Material Adverse Effect.

                  (i) Subsequent to the last date as of which information is
given in the Public Documents, except as contemplated herein, the Company has
not incurred any material liabilities or material obligations, direct or
contingent, or entered into any material transactions not in the ordinary course
of business.

                  (j) The Company has complied and will comply with all
applicable federal and state securities laws in connection with the offer,
issuance and sale of the Shares hereunder. Neither the Company nor anyone acting
on its behalf, directly or indirectly, has or will sell, offer to sell or
solicit offers to buy any of the Shares or solicit offers with respect thereto
from, or enter into any preliminary conversations or negotiations relating
thereto with, any person, or has taken or will take any action so as to bring
the issuance and sale of any of the Shares under the registration provisions of
the Securities Act and any other applicable federal and state securities laws.
Neither the Company nor any of its affiliates, nor any person acting on its or
their behalf, has engaged in (1) any form of general solicitation or general
advertising (within the meaning of Regulation D under the Securities Act) or (2)
any directed selling efforts (within the meaning of Regulation S under the
Securities Act) in connection with any of the Shares.

                  (k) None of this Agreement, the Disclosure Schedule or the
Registration Rights Agreement contains any untrue statement of a material fact
or omits to state a material fact necessary in order to make the statements made
herein or therein, in the light of the circumstances under which they were made
herein or therein, not misleading.

                  (l) The authorized capital stock of the Company and the shares
thereof issued and outstanding as of February 28, 2002 are set forth on Schedule
3(l) of the Disclosure Schedule. All of the outstanding shares of the Company's
Common Stock have been duly and validly authorized, and are fully paid and
non-assessable. Except as set forth in this Agreement, the Public Documents, the
Commission Documents or on Schedule 3(l) of the Disclosure Schedule, as of
February 28, 2002, no shares of Common Stock are entitled to preemptive rights
or registration rights and there are no outstanding options, warrants, scrip,
rights to subscribe to, call or commitments of any character whatsoever relating
to, or securities or rights convertible into, any shares of capital stock of the
Company. Furthermore, except as set forth in this Agreement, in the Public
Documents, the Commission Documents or on Schedule 3(l) of the Disclosure
Schedule, as of the date hereof, there are no contracts, commitments,
understandings, or arrangements by which the Company is or may become bound to
issue additional shares of the capital stock of the Company or options,
securities or rights convertible into shares of capital stock of the Company.
Except as disclosed in the Commission Documents or on Schedule 3(l) of the
Disclosure Schedule, and except for customary transfer restrictions contained in
agreements entered into by the Company in order to sell restricted securities,
as of the date hereof, the Company is not a party to any agreement granting
registration rights to any person with respect to any of its equity or debt
securities. Except as disclosed in the Commission Documents, the Company is not
a party to, and it has no knowledge of, any agreement restricting

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the voting or transfer of any shares of the capital stock of the Company. The
offer and sale of all capital stock, convertible securities, rights, warrants,
or options of the Company issued prior to the Closing complied in all material
respects with all applicable federal and state securities laws, and no
stockholder has a right of rescission or damages with respect thereto which is
reasonably likely to have a Material Adverse Effect. The Company has furnished
or made available to the Purchaser true and correct copies of the Company's
Certificate of Incorporation as in effect on the date hereof (the
"Certificate"), and the Company's Bylaws as in effect on the date hereof (the
"Bylaws").

                  (m) Prior to the effectiveness of the Registration Statement
(as defined in the Registration Rights Agreement), the Company will use all
reasonable commercial best efforts to list the Shares for trading on the New
York Stock Exchange or any relevant market or system on which the Shares are
listed or quoted, if applicable, and will comply in all material respects with
the Company's reporting, filing and other obligations under the bylaws or rules
of the New York Stock Exchange or any relevant market or system.

                  (n) The Company may not issue a press release or otherwise
make a public statement or announcement with respect to the transaction
contemplated hereby prior to the Closing Date without the consent of the
Purchaser, which consent shall not be unreasonably withheld, delayed or
conditioned. In the event that the Company is required by law or regulations to
issue a press release or otherwise make a public statement or announcement with
respect to this Agreement prior to or after the Closing Date, the Company shall
reasonably consult with the Purchaser on the form and substance of such press
release or other disclosure.

                  (o) Neither the Company nor any of its officers or agents
shall disclose any material non-public information about the Company to the
Purchaser.

         4. CONDITIONS PRECEDENT: The obligations hereunder of both the Company
and the Purchaser to enter into this Agreement are subject to their satisfaction
or waiver, at or before the Closing, of each of the conditions set forth below.
These conditions are for the Company's and the Purchaser's sole benefit
respectively, and they may waive their own rights at any time in their sole
discretion.

                  (a) The parties shall have executed and delivered this
Agreement and the Registration Rights Agreement.

                  (b) The Company shall have delivered certificates evidencing
the Shares to the Purchaser.

                  (c) Upon receipt of the certificates evidencing the Shares,
the Purchaser shall have delivered to the Company immediately available funds as
payment in full of the Purchase Price for the Shares.

                  (d) The Purchaser shall have received a legal opinion to be
rendered by inside counsel of the Company or Haynes and Boone, LLP in
substantially the form annexed hereto as Exhibit A, which opinion shall include
reasonable and customary qualifications and limitations

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and, if rendered by Haynes and Boone, LLP, shall be in reliance upon certain
information contained in an officer's certificate from the Company.

         5. LEGENDS. Unless otherwise provided below, each certificate
representing the Shares shall be stamped or otherwise imprinted with a legend
substantially in the following form (the "Legend"):

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
                  "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS AND MAY NOT BE
                  SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF UNLESS REGISTERED
                  UNDER THE SECURITIES ACT AND UNDER APPLICABLE STATE SECURITIES
                  LAWS OR TRINITY INDUSTRIES, INC. (THE "COMPANY") SHALL HAVE
                  RECEIVED AN OPINION, IN FORM, SCOPE AND SUBSTANCE REASONABLY
                  ACCEPTABLE TO THE COMPANY, OF COUNSEL WHO IS REASONABLY
                  ACCEPTABLE TO THE COMPANY THAT REGISTRATION OF SUCH SECURITIES
                  UNDER THE SECURITIES ACT AND UNDER THE PROVISIONS OF
                  APPLICABLE FEDERAL AND STATE SECURITIES LAWS IS NOT REQUIRED."

         6. FEES AND EXPENSES. Each of the Company and the Purchaser shall pay
its respective fees and expenses related to the transactions contemplated by
this Agreement and the Registration Rights Agreement; except that the Company
shall pay on the Closing Date, all reasonable legal fees and expenses, exclusive
of disbursements and out-of-pocket expenses, incurred by the Purchaser of up to
$17,500 in connection with the preparation, negotiation, execution and delivery
of this Agreement and the Registration Rights Agreement. In lieu of the
foregoing payment, the Purchaser may retain such amount at the Closing or
require the Company to pay such amount directly to Purchaser's counsel.

         7. INDEMNIFICATION.

                  (a) The Company hereby agrees to indemnify and hold harmless
the Purchaser and its officers, directors, shareholders, employees, agents,
accountants and attorneys against any and all losses, claims, damages,
liabilities and reasonable expenses incurred by each such person in connection
with defending or investigating any such claims or liabilities, whether or not
resulting in any liability to such person, to which any such indemnified party
may become subject, insofar as such losses, claims, demands, liabilities and
expenses arise out of or are based upon any breach of any representation or
warranty made by the Company in this Agreement.

                  (b) The Purchaser hereby agrees to indemnify and hold harmless
the Company and its officers, directors, shareholders, employees, agents,
accountants and attorneys against any and all losses, claims, damages,
liabilities and expenses incurred by each such person in connection with
defending or investigating any such claims or liabilities, whether or not

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resulting in any liability to such person, to which any such indemnified party
may become subject under the Securities Act, or under any other statute, at
common law or otherwise, insofar as such losses, claims, demands, liabilities
and expenses arise out of or are based upon (i) any untrue statement or alleged
untrue statement of a material fact made by the Purchaser, (ii) any omission or
alleged omission of a material fact with respect to the Purchaser or (iii) any
breach of any representation, warranty or agreement made by the Purchaser in
this Agreement.

         8. GOVERNING LAW; CONSENT TO JURISDICTION. This Agreement shall be
governed by and interpreted in accordance with the laws of the State of New York
without giving effect to the rules governing the conflicts of laws. Each of the
parties consents to the exclusive jurisdiction of the federal courts whose
districts encompass any part of the County of New York located in the City of
New York in connection with any dispute arising under this Agreement and hereby
waives, to the maximum extent permitted by law, any objection, including any
objection based on forum non conveniens, to the bringing of any such proceeding
in such jurisdictions. Each party waives its right to a trial by jury. Each
party to this Agreement irrevocably consents to the service of process in any
such proceeding by the mailing of copies thereof by registered or certified
mail, postage prepaid, to such party at its address set forth at Section 9
herein. Nothing herein shall affect the right of any party to serve process in
any other manner permitted by law.

         9. NOTICES. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, express overnight
courier, registered first class mail, or telecopier, initially to the address
set forth below, and thereafter at such other address, notice of which is given
in accordance with the provisions of this Section.

                           (a)      if to the Company:

                                    Trinity Industries, Inc.
                                    2525 Stemmons Freeway
                                    Dallas, TX 75207
                                    Tel. No.: (214) 631-4420
                                    Fax No.: (214) 589-8824
                                    Attn: Michael G. Fortado

                                    with a copy to:

                                    Haynes and Boone, LLP
                                    901 Main Street, Suite 3100
                                    Dallas, TX 75202
                                    Tel. No.: (214) 651-5587
                                    Fax No.: (214) 200-0674
                                    Attn: W. Scott Wallace, Esq.

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                           (b)      if to the Purchaser:

                                    Acqua Wellington Private Placement Fund,
                                    Ltd.
                                    c/o Fortis Fund Services (Bahamas) Ltd.
                                    Montague Sterling Centre
                                    East Bay Street, P. O. Box SS-6238
                                    Nassau, Bahamas
                                    Tel. No.: (242) 394-2700
                                    Fax No.: (242) 394-9667

                                    with a copy to:

                                    Jenkens & Gilchrist Parker Chapin LLP
                                    The Chrysler Building
                                    405 Lexington Avenue
                                    New York, New York 10174
                                    Attn: Christopher S. Auguste
                                    Tel. No.: (212) 704-6000
                                    Fax No.: (212) 704-6288

         All such notices and communications shall be deemed to have been duly
given: when delivered by hand, if personally delivered; when receipt is
acknowledged, if telecopied; or when actually received or refused if sent by
other means.

         10. ENTIRE AGREEMENT. This Agreement and the Registration Rights
Agreement constitute the entire understanding and agreement of the parties with
respect to the Shares to be purchased hereby and supersede all prior and/or
contemporaneous oral or written proposals or agreements relating thereto all of
which are merged herein. This Agreement may not be amended or any provision
hereof waived in whole or in part, except by a written amendment signed by both
of the parties.

         11. COUNTERPARTS. This Agreement may be executed by facsimile signature
and in counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                                  [END OF PAGE]

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         IN WITNESS WHEREOF, this Agreement was duly executed on the date first
written above.

                                       TRINITY INDUSTRIES, INC.

                                       By: /s/ John L. Adams
                                          --------------------------------------
                                          Name: John L. Adams
                                          Title: Executive Vice President

                                       ACQUA WELLINGTON PRIVATE PLACEMENT FUND,
                                       LTD.

                                       By: /s/ R. Perry Pinder
                                          --------------------------------------
                                          Name: R. Perry Pinder
                                          Title: Vice President

11<PAGE>
                                                                     EXHIBIT 4.6
                               PURCHASE AGREEMENT

         This PURCHASE AGREEMENT (this "Agreement"), dated as of March 6, 2002,
is entered into by and between Trinity Industries, Inc., a Delaware corporation
(the "Company"), and Acqua Wellington Opportunity I Limited, a company organized
under the laws of the Commonwealth of the Bahamas (the "Purchaser"), for the
purchase and sale of shares of the common stock, par value $1.00 per share (the
"Common Stock"), of the Company by the Purchaser, in the manner, and upon the
terms, provisions and conditions set forth in this Agreement.

         WHEREAS, the parties desire that, upon the terms and subject to the
conditions contained herein, the Company shall issue and sell to the Purchaser
and Purchaser shall purchase shares of the Common Stock; and

         WHEREAS, such purchase and sale will be made in reliance upon the
provisions of Section 4(2) or Regulation S ("Regulation S") of the United States
Securities Act of 1933, as amended and regulations promulgated thereunder (the
"Securities Act"), and/or upon such other exemption(s) from the registration
requirements of the Securities Act as may be available with respect to any or
all of the purchases of Common Stock to be made hereunder.

         NOW, THEREFORE, in consideration of the representations, warranties and
agreements contained herein and other good and valuable consideration, the
receipt and legal adequacy of which is hereby acknowledged by the parties, the
Company and the Purchaser hereby agree as follows:

         1. PURCHASE PRICE.

                  (a) Upon the following terms and subject to the conditions
contained herein, the Purchaser hereby agrees to purchase 880,000 shares of the
Company's Common Stock from the treasury of the Company (the "Shares") at a per
share price of $21.00 and for an aggregate purchase price of $18,480,000 (the
"Purchase Price").

                  (b) The Company has authorized and has reserved and covenants
to continue to reserve, free of preemptive rights and other similar contractual
rights of stockholders, a sufficient number of its authorized but unissued
shares of its Common Stock, to effect the issuance of the Shares.

                  (c) The closing (the "Closing") under this Agreement shall
take place at the offices of the Jenkens & Gilchrist Parker Chapin LLP, The
Chrysler Building, 405 Lexington Avenue, New York, New York 10174 at 1:00 p.m.
(eastern time) upon the satisfaction of each of the conditions set forth in
Section 4 hereof (the "Closing Date").

                  (d) The Company shall deliver to the Purchaser on or prior to
the Closing Date a certificate representing the Shares. Upon receipt of the
certificate representing the Shares,

<PAGE>

the Purchaser shall pay the Purchase Price therefor by check, wire transfer or
such other form of payment as shall be mutually agreed upon by the Company and
the Purchaser.

         2. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PURCHASER. The
Purchaser represents and warrants to the Company, and covenants for the benefit
of the Company, as follows:

                  (a) This Agreement has been duly authorized, validly executed
and delivered by the Purchaser and is a valid and binding agreement and
obligation of the Purchaser enforceable against the Purchaser in accordance with
its terms, subject to limitations on enforcement by general principles of equity
and by bankruptcy or other laws affecting the enforcement of creditors' rights
generally, and the Purchaser has full power and authority to execute and deliver
this Agreement and the other agreements and documents contemplated hereby and to
perform its obligations as provided hereunder and thereunder.

                  (b) The Purchaser has received and carefully reviewed copies
of the Public Documents (as hereinafter defined) and has access to the
Commission Documents (as hereinafter defined). The Purchaser understands that no
federal, state, local or foreign governmental body or regulatory authority has
made any finding or determination relating to the fairness of an investment in
any of the Shares and that no federal, state, local or foreign governmental body
or regulatory authority has recommended or endorsed, or will recommend or
endorse, any investment in any of the Shares. The Purchaser, in making the
decision to purchase the Shares, has relied upon independent investigation made
by it and its advisors, if any, and has not relied on any information or
representations made by third parties or by the Company or its officers,
directors, employees, agents, accountants or attorneys. The Purchaser and its
advisors, if any, have been furnished with all materials relating to the
business, finances and operations of the Company and materials relating to the
offer and sale of the Shares which have been requested by the Purchaser. The
Purchaser and its advisors, if any, have been afforded the opportunity to ask
questions of the Company. The Purchaser has sought such accounting, legal and
tax advice as it has considered necessary to make an informed investment
decision with respect to its acquisition of the Shares. The Purchaser
understands that it (and not the Company) shall be responsible for its own tax
liabilities that may arise as a result of this investment or the transactions
contemplated by this Agreement.

                  (c) The Purchaser understands that the Shares are being
offered and sold to it in reliance on specific provisions of federal and state
securities laws and that the Company is relying upon the truth and accuracy of
the representations, warranties, agreements, acknowledgments and understandings
of the Purchaser set forth herein for purposes of qualifying for exemptions from
registration under the Securities Act, and applicable state securities laws.

                  (d) The Purchaser is, and at all times relevant to the offer
to sell the Shares was, an "accredited investor" as defined under Rule 501 of
Regulation D promulgated under the Securities Act.

                  (e) The Purchaser is and will be acquiring the Shares for such
Purchaser's own account, for investment, and not with a view to any resale or
distribution of the Shares in

                                       2
<PAGE>

whole or in part, in violation of the Securities Act or any applicable
securities laws. The Purchaser is not a "U.S. person" within the meaning of
Regulation S under the Securities Act and the Purchaser has executed this
Agreement outside the United States within the meaning of Regulation S under the
Securities Act. To the extent that the instrument representing the Shares is
registered in the name of the Purchaser's nominee, the Purchaser confirms that
such nominee is acting as custodian for the Purchaser of the securities
represented thereby.

                  (f) The offer and sale of the Shares is intended to be exempt
from registration under the Securities Act. The Purchaser understands that the
Shares purchased hereunder have not been, and may never be, registered under the
Securities Act and that none of the Shares can be sold or transferred unless
they are first registered under the Securities Act and such state and other
securities laws as may be applicable or, in the opinion of counsel reasonably
acceptable to the Company, an exemption from registration under the Securities
Act is available (and then the Shares may be sold or transferred only in
compliance with such exemption and all applicable state and other securities
laws to the reasonable satisfaction of counsel for the Company). The Purchaser
will not sell any of the Shares in violation of this Section 2(f).

                  (g) The Purchaser (i) has such knowledge and experience in
financial and business matters as to be capable of evaluating the merits and
risks of an investment in the Company; and (ii) recognizes that such Purchaser's
investment in the Company involves a high degree of risk.

                  (h) The Purchaser is capable of evaluating the risks and
merits of an investment in the Shares by virtue of its experience as an investor
and its knowledge, experience, and sophistication in financial and business
matters and such Purchaser is capable of bearing the entire loss of its
investment in the Shares.

                  (i) The Purchaser is neither a registered broker-dealer nor an
affiliate of a registered broker-dealer.

                  (j) Neither the Purchaser nor any of its affiliates, officers
or agents will solicit any material non-public information from the Company.

                  (k) The Purchaser has no agreement or arrangement with the
Company or with any third party for the sale or disposition of the Common Stock
to be purchased pursuant to this Agreement.

                  (l) The Purchaser covenants with the Company as follows: The
Purchaser's trading and distribution activities with respect to the Shares will
be in compliance with all applicable state and federal securities laws, rules
and regulations (including, without limitation, regulation M promulgated under
the Securities Act) and the rules and regulations of the New York Stock
Exchange. Neither the Purchaser nor any of its affiliates (as that term is
defined in Rule 405 promulgated under the Securities Act) has taken, nor will
any of them take, directly or indirectly, any action designed to cause or that
would result in, or which constitutes or that might reasonably be expected to
constitute, the stabilization or manipulation of the price of the Common Stock
to facilitate the purchase, sale or resale of the Common Stock or the Shares.

                                       3
<PAGE>

                  (m) The Purchaser is a company duly organized, validly
existing and in good standing under the laws of the Commonwealth of the Bahamas.

                  (n) The execution and delivery of this Agreement and the
Registration Rights Agreement, the acquisition of any of the Shares and the
consummation of the transactions contemplated by this Agreement and the
Registration Rights Agreement by the Purchaser, will not (i) conflict with or
result in a breach of or a default under any of the terms or provisions of
Purchaser's organizational documents, or (ii) result in a violation of any
material provision of any law, statute, rule, regulation, or any existing
applicable decree, judgment or order by any court, federal or state regulatory
body, administrative agency, or other governmental body having jurisdiction over
the Purchaser.

         3. REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY. The
Company represents and warrants to the Purchaser, and covenants for the benefit
of the Purchaser, as of the date of this Agreement, that except as set forth in
the disclosure schedule of even date hereof delivered to Purchaser by the
Company (the "Disclosure Schedule"), which exceptions shall be deemed to be a
part of and to qualify the representations and warranties to which they refer as
if made hereunder:

                  (a) The Company has been duly incorporated and is validly
existing and in good standing under the laws of the state of Delaware, with full
corporate power and authority to own, lease and operate its properties and to
conduct its business as currently conducted, and is duly registered and
qualified to conduct its business and is in good standing in each jurisdiction
or place where the nature of its properties or the conduct of its business
requires such registration or qualification, except where the failure to
register or qualify would not have a Material Adverse Effect. For purposes of
this Agreement, "Material Adverse Effect" shall mean any effect on the business,
prospects, operations, properties or financial condition of the Company that is
material and adverse to the Company and its subsidiaries, taken as a whole.

                  (b) The Company has furnished the Purchaser with copies of the
Company's most recent Annual Report on Form 10-K for fiscal year ended March 31,
2001 (the "Form 10-K") filed with the Securities and Exchange Commission (the
"Commission") and its Form 10-Q for the quarterly period ended September 30,
2001 as amended by its Form 10-Q/A filed with the Commission on November 21,
2001 (the "Form 10-Q" and its current reports on Form 8-K filed on the following
dates: August 1, 2001, August 16, 2001, September 18, 2001 and October 29, 2001
(as amended by its Form 8-K/A filed on December 28, 2001) (collectively, the
"Form 8-Ks," and together with the Form 10-K and the Form 10-Q, the "Public
Documents"). The Public Documents at the time of their filing did not include
any untrue statement of a material fact or omit to state any material fact
necessary in order to make the statements contained therein, in light of the
circumstances under which they were made, not misleading. As used herein,
"Commission Documents" means all reports, schedules, forms, statements and other
documents filed by the Company with the Commission pursuant to the reporting
requirements of the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), including material filed pursuant to Section 13(a) or 15(d) of the
Exchange Act.

                                       4
<PAGE>

                  (c) The Shares have been duly authorized by all necessary
corporate action and, when paid for by the Purchaser and issued in accordance
with the terms hereof, the Shares shall be validly issued, will be fully paid
and non-assessable.

                  (d) Each of this Agreement and the Registration Rights
Agreement attached hereto as Exhibit A (the "Registration Rights Agreement") has
been duly authorized, validly executed and delivered on behalf of the Company
and is a valid and binding agreement and obligation of the Company enforceable
against the Company in accordance with its terms, subject to limitations on
enforcement by general principles of equity and by bankruptcy or other laws
affecting the enforcement of creditors' rights generally, and the Company has
full power and authority to execute and deliver this Agreement and the other
agreements and documents contemplated hereby and to perform its obligations
hereunder and thereunder.

                  (e) The execution and delivery of this Agreement and the
Registration Rights Agreement, the issuance of any of the Shares and the
consummation of the transactions contemplated by this Agreement and the
Registration Rights Agreement by the Company, will not (i) conflict with or
result in a breach of or a default under any of the terms or provisions of, (A)
the Company's certificate of incorporation or by-laws, or (B) of any provision
of any material indenture, mortgage, deed of trust or other material agreement
or instrument to which the Company is a party or by which it or any of its
material properties or assets is bound, (ii) result in a violation of any
material provision of any law, statute, rule, regulation, or any existing
applicable decree, judgment or order by any court, federal or state regulatory
body, administrative agency, or other governmental body having jurisdiction over
the Company, or any of its material properties or assets or (iii) result in the
creation or imposition of any material lien, charge or encumbrance upon any
material property or assets of the Company or any of its subsidiaries pursuant
to the terms of any agreement or instrument to which any of them is a party or
by which any of them may be bound or to which any of their property or any of
them is subject except in the case of clauses (i)(B) or (iii) for any such
conflicts, breaches, or defaults or any liens, charges, or encumbrances which
would not have a Material Adverse Effect.

                  (f) The sale and issuance of the Shares in accordance with the
terms and on the basis of the representations and warranties set forth in this
Agreement will be exempt from the registration requirements of the Securities
Act.

                  (g) No consent, approval or authorization of or designation,
declaration or filing with any governmental authority on the part of the Company
is required in connection with the valid execution and delivery of this
Agreement or the offer, sale or issuance of the Shares or the consummation of
any other transaction contemplated by this Agreement (other than any filings
which may be required to be made by the Company with the Commission, or New York
Stock Exchange or pursuant to any state or "blue sky" securities laws, and, any
registration statement which have been made or may be filed pursuant to this
Agreement).

                  (h) There is no action, suit, claim or proceeding before or by
any court or governmental agency or body, domestic or foreign, now pending
against or affecting the Company, or any of its properties, which questions the
validity of this Agreement, the Registration Rights Agreement or the
transactions contemplated thereby or any action taken or to

                                       5
<PAGE>

be take pursuant thereto. Except as described in the Public Documents, there is
no action, suit, claim or proceeding before or by any court or governmental
agency or body, domestic or foreign, now pending against or affecting the
Company, or any of its properties, which, if adversely determined, is reasonably
likely to result in a Material Adverse Effect.

                  (i) Subsequent to the last date as of which information is
given in the Public Documents, except as contemplated herein, the Company has
not incurred any material liabilities or material obligations, direct or
contingent, or entered into any material transactions not in the ordinary course
of business.

                  (j) The Company has complied and will comply with all
applicable federal and state securities laws in connection with the offer,
issuance and sale of the Shares hereunder. Neither the Company nor anyone acting
on its behalf, directly or indirectly, has or will sell, offer to sell or
solicit offers to buy any of the Shares or solicit offers with respect thereto
from, or enter into any preliminary conversations or negotiations relating
thereto with, any person, or has taken or will take any action so as to bring
the issuance and sale of any of the Shares under the registration provisions of
the Securities Act and any other applicable federal and state securities laws.
Neither the Company nor any of its affiliates, nor any person acting on its or
their behalf, has engaged in (1) any form of general solicitation or general
advertising (within the meaning of Regulation D under the Securities Act) or (2)
any directed selling efforts (within the meaning of Regulation S under the
Securities Act) in connection with any of the Shares.

                  (k) None of this Agreement, the Disclosure Schedule or the
Registration Rights Agreement contains any untrue statement of a material fact
or omits to state a material fact necessary in order to make the statements made
herein or therein, in the light of the circumstances under which they were made
herein or therein, not misleading.

                  (l) The authorized capital stock of the Company and the shares
thereof issued and outstanding as of February 28, 2002 are set forth on Schedule
3(l) of the Disclosure Schedule. All of the outstanding shares of the Company's
Common Stock have been duly and validly authorized, and are fully paid and
non-assessable. Except as set forth in this Agreement, the Public Documents, the
Commission Documents or on Schedule 3(l) of the Disclosure Schedule, as of
February 28, 2002, no shares of Common Stock are entitled to preemptive rights
or registration rights and there are no outstanding options, warrants, scrip,
rights to subscribe to, call or commitments of any character whatsoever relating
to, or securities or rights convertible into, any shares of capital stock of the
Company. Furthermore, except as set forth in this Agreement, in the Public
Documents, the Commission Documents or on Schedule 3(l) of the Disclosure
Schedule, as of the date hereof, there are no contracts, commitments,
understandings, or arrangements by which the Company is or may become bound to
issue additional shares of the capital stock of the Company or options,
securities or rights convertible into shares of capital stock of the Company.
Except as disclosed in the Commission Documents or on Schedule 3(l) of the
Disclosure Schedule, and except for customary transfer restrictions contained in
agreements entered into by the Company in order to sell restricted securities,
as of the date hereof, the Company is not a party to any agreement granting
registration rights to any person with respect to any of its equity or debt
securities. Except as disclosed in the Commission Documents, the Company is not
a party to, and it has no knowledge of, any agreement restricting

                                       6
<PAGE>

the voting or transfer of any shares of the capital stock of the Company. The
offer and sale of all capital stock, convertible securities, rights, warrants,
or options of the Company issued prior to the Closing complied in all material
respects with all applicable federal and state securities laws, and no
stockholder has a right of rescission or damages with respect thereto which is
reasonably likely to have a Material Adverse Effect. The Company has furnished
or made available to the Purchaser true and correct copies of the Company's
Certificate of Incorporation as in effect on the date hereof (the
"Certificate"), and the Company's Bylaws as in effect on the date hereof (the
"Bylaws").

                  (m) Prior to the effectiveness of the Registration Statement
(as defined in the Registration Rights Agreement), the Company will use all
reasonable commercial best efforts to list the Shares for trading on the New
York Stock Exchange or any relevant market or system on which the Shares are
listed or quoted, if applicable, and will comply in all material respects with
the Company's reporting, filing and other obligations under the bylaws or rules
of the New York Stock Exchange or any relevant market or system.

                  (n) The Company may not issue a press release or otherwise
make a public statement or announcement with respect to the transaction
contemplated hereby prior to the Closing Date without the consent of the
Purchaser, which consent shall not be unreasonably withheld, delayed or
conditioned. In the event that the Company is required by law or regulations to
issue a press release or otherwise make a public statement or announcement with
respect to this Agreement prior to or after the Closing Date, the Company shall
reasonably consult with the Purchaser on the form and substance of such press
release or other disclosure.

                  (o) Neither the Company nor any of its officers or agents
shall disclose any material non-public information about the Company to the
Purchaser.

         4. CONDITIONS PRECEDENT: The obligations hereunder of both the Company
and the Purchaser to enter into this Agreement are subject to their satisfaction
or waiver, at or before the Closing, of each of the conditions set forth below.
These conditions are for the Company's and the Purchaser's sole benefit
respectively, and they may waive their own rights at any time in their sole
discretion.

                  (a) The parties shall have executed and delivered this
Agreement and the Registration Rights Agreement.

                  (b) The Company shall have delivered certificates evidencing
the Shares to the Purchaser.

                  (c) Upon receipt of the certificates evidencing the Shares,
the Purchaser shall have delivered to the Company immediately available funds as
payment in full of the Purchase Price for the Shares.

                  (d) The Purchaser shall have received a legal opinion to be
rendered by inside counsel of the Company or Haynes and Boone, LLP in
substantially the form annexed hereto as Exhibit A, which opinion shall include
reasonable and customary qualifications and limitations

                                       7
<PAGE>

and, if rendered by Haynes and Boone, LLP, shall be in reliance upon certain
information contained in an officer's certificate from the Company.

         5. LEGENDS. Unless otherwise provided below, each certificate
representing the Shares shall be stamped or otherwise imprinted with a legend
substantially in the following form (the "Legend"):

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
                  "SECURITIES ACT"), OR ANY STATE SECURITIES LAWS AND MAY NOT BE
                  SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF UNLESS REGISTERED
                  UNDER THE SECURITIES ACT AND UNDER APPLICABLE STATE SECURITIES
                  LAWS OR TRINITY INDUSTRIES, INC. (THE "COMPANY") SHALL HAVE
                  RECEIVED AN OPINION, IN FORM, SCOPE AND SUBSTANCE REASONABLY
                  ACCEPTABLE TO THE COMPANY, OF COUNSEL WHO IS REASONABLY
                  ACCEPTABLE TO THE COMPANY THAT REGISTRATION OF SUCH SECURITIES
                  UNDER THE SECURITIES ACT AND UNDER THE PROVISIONS OF
                  APPLICABLE FEDERAL AND STATE SECURITIES LAWS IS NOT REQUIRED."

         6. FEES AND EXPENSES. Each of the Company and the Purchaser shall pay
its respective fees and expenses related to the transactions contemplated by
this Agreement and the Registration Rights Agreement; except that the Company
shall pay on the Closing Date, all reasonable legal fees and expenses, exclusive
of disbursements and out-of-pocket expenses, incurred by the Purchaser of up to
$17,500 in connection with the preparation, negotiation, execution and delivery
of this Agreement and the Registration Rights Agreement. In lieu of the
foregoing payment, the Purchaser may retain such amount at the Closing or
require the Company to pay such amount directly to Purchaser's counsel.

         7. INDEMNIFICATION.

                  (a) The Company hereby agrees to indemnify and hold harmless
the Purchaser and its officers, directors, shareholders, employees, agents,
accountants and attorneys against any and all losses, claims, damages,
liabilities and reasonable expenses incurred by each such person in connection
with defending or investigating any such claims or liabilities, whether or not
resulting in any liability to such person, to which any such indemnified party
may become subject, insofar as such losses, claims, demands, liabilities and
expenses arise out of or are based upon any breach of any representation or
warranty made by the Company in this Agreement.

                  (b) The Purchaser hereby agrees to indemnify and hold harmless
the Company and its officers, directors, shareholders, employees, agents,
accountants and attorneys against any and all losses, claims, damages,
liabilities and expenses incurred by each such person in connection with
defending or investigating any such claims or liabilities, whether or not

                                       8
<PAGE>

resulting in any liability to such person, to which any such indemnified party
may become subject under the Securities Act, or under any other statute, at
common law or otherwise, insofar as such losses, claims, demands, liabilities
and expenses arise out of or are based upon (i) any untrue statement or alleged
untrue statement of a material fact made by the Purchaser, (ii) any omission or
alleged omission of a material fact with respect to the Purchaser or (iii) any
breach of any representation, warranty or agreement made by the Purchaser in
this Agreement.

         8. GOVERNING LAW; CONSENT TO JURISDICTION. This Agreement shall be
governed by and interpreted in accordance with the laws of the State of New York
without giving effect to the rules governing the conflicts of laws. Each of the
parties consents to the exclusive jurisdiction of the federal courts whose
districts encompass any part of the County of New York located in the City of
New York in connection with any dispute arising under this Agreement and hereby
waives, to the maximum extent permitted by law, any objection, including any
objection based on forum non conveniens, to the bringing of any such proceeding
in such jurisdictions. Each party waives its right to a trial by jury. Each
party to this Agreement irrevocably consents to the service of process in any
such proceeding by the mailing of copies thereof by registered or certified
mail, postage prepaid, to such party at its address set forth at Section 9
herein. Nothing herein shall affect the right of any party to serve process in
any other manner permitted by law.

         9. NOTICES. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, express overnight
courier, registered first class mail, or telecopier, initially to the address
set forth below, and thereafter at such other address, notice of which is given
in accordance with the provisions of this Section.

                           (a)      if to the Company:

                                    Trinity Industries, Inc.
                                    2525 Stemmons Freeway
                                    Dallas, TX 75207
                                    Tel. No.: (214) 631-4420
                                    Fax No.: (214) 589-8824
                                    Attn: Michael G. Fortado

                                    with a copy to:

                                    Haynes and Boone, LLP
                                    901 Main Street, Suite 3100
                                    Dallas, TX 75202
                                    Tel. No.: (214) 651-5587
                                    Fax No.: (214) 200-0674
                                    Attn: W. Scott Wallace, Esq.

                                       9
<PAGE>

                           (b)      if to the Purchaser:

                                    Acqua Wellington Opportunity I Limited
                                    Shirlaw House
                                    87 Shirley Street
                                    P.O. Box SS-19084
                                    Nassau, Bahamas
                                    Fax No.: (242) 328-6919
                                    Attn: Michael Taylor

                                    with a copy to:

                                    Jenkens & Gilchrist Parker Chapin LLP
                                    The Chrysler Building
                                    405 Lexington Avenue
                                    New York, New York 10174
                                    Attn: Christopher S. Auguste
                                    Tel. No.: (212) 704-6000
                                    Fax No.: (212) 704-6288

         All such notices and communications shall be deemed to have been duly
given: when delivered by hand, if personally delivered; when receipt is
acknowledged, if telecopied; or when actually received or refused if sent by
other means.

         10. ENTIRE AGREEMENT. This Agreement and the Registration Rights
Agreement constitute the entire understanding and agreement of the parties with
respect to the Shares to be purchased hereby and supersede all prior and/or
contemporaneous oral or written proposals or agreements relating thereto all of
which are merged herein. This Agreement may not be amended or any provision
hereof waived in whole or in part, except by a written amendment signed by both
of the parties.

         11. COUNTERPARTS. This Agreement may be executed by facsimile signature
and in counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                                  [END OF PAGE]

                                       10
<PAGE>

         IN WITNESS WHEREOF, this Agreement was duly executed on the date first
written above.

                                       TRINITY INDUSTRIES, INC.

                                       By: /s/ John L. Adams
                                          --------------------------------------
                                          Name: John L. Adams
                                          Title: Executive Vice President

                                       ACQUA WELLINGTON OPPORTUNITY I LIMITED

                                       By: /s/ Dayrrl Butler
                                          --------------------------------------
                                          Name: Dayrrl Butler
                                          Title: Director

                                       11

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