Document:

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                                                                   EXHIBIT 10.15
                         PROMISSORY NOTE

Date:                    March 2, 2000

Maker:                   Eugene P. Martineau

Maker's Mailing Address: c/o U.S. Concrete, Inc.
                         1300 Post Oak Blvd., Suite 1220
                         Houston, Texas  77056

Payee:                   USC Management Co., L.P.,
                         a Texas limited partnership

Place for Payment:       1300 Post Oak Blvd., Suite 1220
                         Houston, Texas  77056

Principal Amount:        $175,000.00, or such lesser amount as has been advanced
                         by Payee to Maker and is outstanding from time to time.

Terms of Payment:        This is a non-interest bearing promissory note.
                         Principal shall be payable from time to time prior to
                         March 1, 2005 within 10 business days of receipt by
                         Maker of any Net Cash Proceeds (as defined herein),
                         until the principal amount is paid in full.  The
                         outstanding principal amount shall be due and payable
                         in full on or before March 1, 2005.

Security for Payment:    This note is secured by any and all cash proceeds
                         received by Maker (net of any broker's fee or other
                         reasonable and customary transaction expenses and of
                         amounts reasonably estimated to be necessary to pay
                         income or capital gains taxes resulting from receipt of
                         such proceeds) during the period beginning March 2,
                         2000 and ending upon the earlier of payment in full of
                         this note or March 1, 2005 from (a) the sale by Maker
                         of all shares of common stock, $.001 par value ("Common
                         Stock"), of U.S. Concrete, Inc., a Delaware corporation
                         ("USC"), acquired by Maker through the exercise of any
                         option to purchase Common Stock and (b) the payment to
                         Maker by USC or Payee of such portion of any bonuses as
                         may be mutually agreed upon by Maker and Payee (any
                         such net cash proceeds described in subparts (a) and
                         (b) shall be referred to herein as "Net Cash
                         Proceeds").

     FOR VALUE RECEIVED, Maker promises to pay to the order of Payee at the
place for payment and according to the terms of payment (in funds available for
immediate use) the principal amount.  All unpaid amounts shall be due by the
final scheduled payment date.
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     If Maker defaults in the payment of this note or in the performance of any
obligation securing or collateral to it, and the default continues after Payee
gives Maker notice of the default and the time within which it must be cured, as
may be required by Payee, then Payee may declare the unpaid balance on this note
immediately due.  Maker and each surety, endorser and guarantor waive all
demands for payment, presentations for payment, notices of intention to
accelerate maturity, notices of acceleration of maturity, protests and notices
of protest, to the extent permitted by law.

     If this note is given to an attorney for collection, or if suit is brought
for collection, or if it is collected through probate, bankruptcy, or other
judicial proceeding, then Maker shall pay Payee all costs of collection,
including reasonable attorney's fees and court costs, in addition to other
amounts due.

     Neither a delay on the part of Payee in the exercise of any power or right
under this note, nor a single or partial exercise of any such power or right,
shall operate as a waiver thereof.  Enforcement by Payee of any of its rights
hereunder shall not constitute an election by it of remedies so as to preclude
the exercise of any other remedy available to it.

     Unless this note is paid at its maturity, or when otherwise due, as herein
provided, any money, securities or property on deposit with, in possession or
under the control of, or held by USC or Payee, for any purpose whatsoever,
including, without limitation, for payment of salary or bonuses to Maker, or in
transit to or from Payee by mail or carrier to the credit or for the account of
Maker, or any of them, may, at the option of Payee, be applied to the payment of
this note or any other debt, liability or obligation, direct or contingent, due
or to become due, by Maker to Payee or USC.

     This note may be prepaid in whole or in part at any time, without penalty.

     THIS NOTE IS DELIVERED AND IS INTENDED TO BE PAID AND PERFORMED IN THE
STATE OF TEXAS, AND THE LAWS OF SUCH STATE SHALL GOVERN THE CONSTRUCTION,
VALIDITY, ENFORCEMENT, AND INTERPRETATION HEREOF.

     All of the covenants, stipulations, promises, and agreements contained in
this note made by or on behalf of Maker shall bind its successors and assigns,
whether so expressed or not; provided, however, that Maker may not, without
prior written consent of the holder hereof, assign any rights, duties, or
obligations under this note.

     Each Maker is responsible for all obligations represented by this note.

     When the context requires, the terms Maker and Payee, and other singular
nouns and pronouns include the plural.

                                    MAKER

                                    /s/ Eugene P. Martineau
                                    -----------------------
                                    Eugene P. Martineau<PAGE>

                                                                   EXHIBIT 10.16
                                   AGREEMENT

     THIS AGREEMENT (this "Agreement") is entered into effective as of March 13,
2001, by and between U.S. Concrete, Inc., a Delaware corporation ("USC"), and
Neil J. Vannucci ("Vannucci").

                                    RECITALS

     WHEREAS, USC, Bay Cities Acquisition Inc., a Delaware corporation and
wholly owned subsidiary of USC, Bay Cities Building Materials Co., Inc., a
California corporation ("Bay Cities"), Vannucci and other former stockholders of
Bay Cities entered into that certain Agreement and Plan of Reorganization
Agreement, dated as of March 22, 1999 and as amended by the Amendment to
Agreement and Plan of Reorganization among the same parties dated as of May 25,
1999, (as amended, the "Acquisition Agreement"); and

     WHEREAS, pursuant to the terms of the Acquisition Agreement, Vannucci
agreed to be bound by the noncompetition provisions contained in Article VIII
thereof; provided, however, that Paragraph 4(C) of the Acquisition Agreement
specified certain activities that the provisions of Article VIII thereof would
not prohibit Vanucci from engaging in (the provisions of Paragraph 4(C) of the
Acquisition Agreement being hereinafter referred to as the "Exception
Provisions"); and

     WHEREAS, USC desires that Vannucci agree not conduct any activities that
would be permitted under the Exception Provisions and Vanucci is willing to (i)
refrain from engaging in any of those activities and (ii) agree to the other
restrictions on his activities and commit to take the actions specified herein,
all on the terms and subject to the conditions set forth in this Agreement.

     NOW, THEREFORE, in consideration of the foregoing and the mutual provisions
contained herein, and for other good and valuable consideration, the parties
hereto agree with each other as follows:

     1.   Payment Option and Restricted Activities.

     (a)  USC shall have the option to make payments to Vannucci in the
aggregate amount of $138,000.00 during each of the 12-month periods beginning
April 1, 2001, 2002 and 2003 and ending March 31, 2002, 2003 and 2004,
respectively (each, an "Option Period" and each aggregate payment of $138,000.00
made by USC during an Option Period, an "Option Period Payment").  In
consideration of the foregoing, during the Restricted Term (as defined herein)
the Exception Provisions shall not be applicable and, without limiting the
generality of the foregoing and notwithstanding anything to the contrary
contained in the Acquisition Agreement, Vannucci shall not, during the
Restricted Term, directly or indirectly, for himself or on behalf of or in
conjunction with

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any other person, company, partnership, corporation or business or other entity
of whatever nature, engage, as an officer, director, shareholder, owner,
investor, partner, joint venturer, or in any managerial or advisory capacity,
whether as an employee, independent contractor, consultant or advisor, or as a
sales representative, dealer or distributor, in any Restricted Activities (as
defined herein) within any State of the United States where USC or any of its
subsidiaries then conducts business.

     (b)  For purposes of this Agreement "Restricted Activities" means the
import, storage or sale of cement and/or aggregates, including, without
limitation, the development, ownership and/or operation of any import terminal
or other facility used or intended to be used, in whole or in part, for the
import, storage or sale of cement and/or aggregates.

     (c)  For purposes of this Agreement "Restricted Term" means the period
beginning on the date hereof and continuing through: (i) March 31, 2002, if USC
fails to make the first Option Period Payment in full by that date; (ii) March
31, 2003, if USC makes the first Option Period Payment in full by March 31, 2002
but does not make the second Option Period Payment in full by March 31, 2003;
(iii) March 31, 2004, if USC satisfies the condition of subpart (ii) of this
Section 1(c) and makes the second Option Period Payment in full by March 31,
2003 but does not make the third Option Period Payment in full by March 31,
2004; and (iv) March 31, 2005, if USC satisfies the conditions of subparts (ii)
and (iii) of this Section 1(c) and makes the third Option Period Payment in full
by March 31, 2004.

     (d)  The Option Period Payment USC may make during any Option Period shall
be in three cash installments of $46,000.00 each, payable on such dates during
such Option Period as USC may determine, in each case to such account or
accounts as Vannucci shall specify to USC in writing.

     (e)  Without limiting the generality of the restrictive covenants set forth
in Section 1 herein, Vannucci specifically agrees not to pursue or lend
assistance to any person or entity in obtaining any permits or authorizations he
may have applied for or otherwise sought (whether in his name individually or on
behalf of any entity in which he is or was a stockholder, member or partner) in
connection with the development or operation of a cement and/or aggregates
import terminal in or near the San Francisco Bay Area and shall use reasonable
efforts to withdraw such permits or, if any such permits were applied for
jointly with another person or entity, have his name and/or the name of any such
entity in which he is or was a stockholder, member or partner removed from such
permits or authorizations.

     (f)  In the event of any breach or threatened breach by Vannucci of any
provision of this Agreement, USC will be entitled, in addition to any other
remedies that it may have at law or in equity, to injunctive relief or an order
of specific performance.  No failure or delay by USC in exercising any right,
power or privilege hereunder will operate as a waiver thereof, nor will any
single or partial exercise thereof preclude any

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other or further exercise thereof or the exercise of any other right, power or
privilege hereunder.

     2.   No Prior Agreements.   Vannucci represents and warrants to USC
that neither the execution and delivery of this Agreement by Vannucci nor his
compliance with the restrictions and other provisions contained herein will
violate, breach or conflict with any agreement, arrangement or understanding
with any other person or entity.  Further, Vannucci agrees to indemnify USC from
and against any claim, liability, loss, cost or expense, including but not
limited to attorneys' fees and expenses of investigation, arising out of or
resulting from any claim by any third party to the effect that this Agreement
violates, breaches or conflicts in any way with any other agreement to which
Vanucci or any of his affiliates is a party or is bound.

     3.   Reaffirmation of Limitations on Competition.  Vannucci hereby ratifies
and affirms his obligations under Article VIII of the Acquisition Agreement
(Limitations on Competition) and all other provisions of the Acquisition
Agreement that continue to survive in accordance with their terms.

     4.   General.  This Agreement may be amended only by the written agreement
of each party hereto.  Each party hereto agrees to perform any further acts and
to execute and deliver any further documents which may be reasonably necessary
to carry out the provisions of this Agreement.  This Agreement shall be binding
on and inure to the benefit of each party hereto, and such party's successors,
personal representatives and assigns.  This Agreement sets forth the entire
understanding between the parties hereto concerning the subject matter of this
Agreement.  In the event that any court of competent jurisdiction shall
determine that the scope, time or territorial restrictions set forth in Section
1 of this Agreement are unreasonable, then it is the intention of the parties
that such restrictions be enforced to the fullest extent which the court deems
reasonable, and this Agreement shall be reformed in accordance therewith.  This
Agreement shall be governed by the laws of the State of Texas.  This Agreement
may be executed in one or more counterparts, any of which shall be deemed to be
an original, all of which taken together shall constitute one and the same
instrument.  Facsimile transmission of any signed original document and/or
retransmission of any signed facsimile transmission will be deemed the same as
delivery of an original.  At the request of any party, the parties will confirm
facsimile transmission by signing a duplicate original document.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
the date first written above.

                                   U.S. CONCRETE, INC.

                                   By: /s/ Eugene P. Martineau
                                       --------------------------
                                       Eugene P. Martineau, President

                                   /s/ Neil J. Vannucci
                                   ------------------------------
                                   Neil J. Vannucci

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