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                                                                    Exhibit 3.10

                                     BYLAWS

                                       OF

                              QUINCY JOIST COMPANY

                  The original corporate records have been misplaced. The
         following Bylaws are Adopted as of the date of incorporation to replace
         the lost Bylaws.



                               ARTICLE I - OFFICES

         The office of the corporation shall be located in the City, County and
State designated in the Certificate of Incorporation. The corporation may also
maintain offices at such other places within or without the United States as the
Board of Directors may, from time to time, determine.

                      ARTICLE II - MEETING OF SHAREHOLDERS

Section 1 - Annual Meetings:

         The annual meeting of the shareholders of the corporation shall be held
within five (5) months after the close of the fiscal year of the corporation for
the purpose of electing directors and transacting such other business as may
properly come before the meeting.

Section 2 - Special Meetings:

         Special meetings of the shareholders may be called at any time by the
Board of Directors or by the President, and shall be called by the President or
the Secretary at the written request of the holders of twenty-five percent (25%)
of the shares then outstanding and entitled to vote thereat, or as otherwise
required by law.

Section 3 - Place of Meetings:

         All meetings of shareholders shall be held at the principal office of
the corporation or at such other places as shall be designated in the notices or
waivers of notice of such meetings.

Section 4 - Notice of Meetings:

         (a) Except as otherwise provided by statute, written notice of each
meeting of shareholders, whether annual or special, stating the time when and
place where it is to be held, shall be served either personally or by mail, not
less than ten (10) or more than fifty (50) days before the meeting, upon each
shareholder of record entitled to vote at such meeting, and to any other


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shareholder to whom the giving of notice may be required by law. Notice of a
special meeting shall also state the purpose or purposes for which the meeting
is called, and shall indicate that it is being issued by, or at the direction
of, the person or persons calling the meeting. If, at any meeting, action is
proposed to be taken that would, if taken, entitle shareholders to receive
payment for their shares pursuant to statute, the notice of such meeting shall
include a statement of that purpose and to that effect. If mailed, such notice
shall be directed to each such shareholder at his address, as it appears on the
records of the shareholders of the corporation, unless he shall have previously
filed with the Secretary of the corporation a written request that notices
intended for him to be mailed to some other address, in which case, it shall be
mailed to the address designated in such request.

         (b) Notice of any meeting need not be given to any person who may
become a shareholder of record after the mailing of such notice and prior to the
meeting, or to any shareholder who attends such meeting, in person or by proxy,
or to any shareholder who, in person or by proxy, submits a signed waiver of
notice either before or after such meeting. Notice of any adjourned meeting of
shareholders need not be given, unless otherwise required by statute.

Section 5 - Quorum:

         (a) Except as otherwise provided herein, or by statute, or in the
Certificate of Incorporation (such Certificate and any Amendments thereof being
hereinafter collectively referred to as the "Certificate of Incorporation"), at
all meetings of shareholders of the corporation, the presence at the
commencement of such meetings in person or by proxy of shareholders holding of
record a majority of the total number of shares of the corporation then issued
and outstanding and entitled to vote, shall be necessary and sufficient to
constitute a quorum for the transaction of any business. The withdrawal of any
shareholder after the commencement of a meeting shall have no effect on the
existence of a quorum, after a quorum has been established at such meeting.

         (b) Despite the absence of a quorum at any annual or special meeting of
shareholders, the shareholders, by a majority of the votes cast by the holders
of shares entitled to vote thereon, may adjourn the meeting. At any such
adjourned meeting at which a quorum is present, any business may be transacted
at the meeting as originally called if a quorum had been present.

Section 6 - Voting:

         (a) Except as otherwise provided by statute or by the Certificate of
Incorporation, any corporate action, other than the election of directors, to be
taken by vote of the shareholders, shall be authorized by a majority of votes
cast at a meeting of shareholders by the holders of shares entitled to vote
thereon.

         (b) Except as otherwise provided by statute or by the Certificate of
Incorporation, at each meeting of shareholders, each holder of record of stock
of the corporation entitled to vote thereat, shall be entitled to one (1) vote
for each share of stock registered in his name on the books of the corporation.


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         (c) Each shareholder entitled to vote or to express consent or dissent
without a meeting, may do so by proxy; provided, however, that the instrument
authorizing such proxy to act shall have been executed in writing by the
shareholder himself, or by his attorney in fact thereunto duly authorized in
writing. No proxy shall be valid after the expiration of eleven (11) months from
the date of its execution, unless the person executing it shall have specified
therein the length of time it is to continue in force. Such instrument shall be
exhibited to the Secretary at the meeting and shall be filed with the records of
the corporation.

         (d) Any resolution in writing, signed by all of the shareholders
entitled to vote thereon, shall be and constitute action by such shareholders to
the effect therein expressed, with the same force and effect as if the same had
been duly passed by unanimous vote at a duly called meeting of shareholders and
such resolution so signed shall be inserted in the minute book of the
corporation under its proper date.

                        ARTICLE III - BOARD OF DIRECTORS

Section 1 - Number, Election and Term of Office:

         (a) The number of directors of the corporation shall be not less than
three (3), unless all of the outstanding shares are owned beneficially and of
record by less than three (3) shareholders, in which event the number of
directors shall not be less than the number of shareholders permitted by
statute.

         (b) Except as may otherwise be provided herein or in the Certificates
of Incorporation, the members of the Board of Directors of the corporation who
need not be shareholders shall be elected by majority of the votes cast at a
meeting of shareholders, by the holders of shares, present in person or by
proxy, entitled to vote in the election.

         (c) Each director shall hold office until the annual meeting of the
shareholders next succeeding his election, and until his successor is elected
and qualified, or until his prior death, resignation or removal.

Section 2 - Duties and Powers:

         (a) A regular annual meeting of the Board of Directors shall be held
immediately following the annual meeting of the shareholders, at the place of
such annual meeting of shareholders.

         (b) The Board of Directors, from time to time, may provide by
resolution for the holding of other regular meetings of the Board of Directors,
and may fix the time and place thereof.

         (c) Notice of any regular meeting of the Board of Directors shall not
be required to be given and, if given, need not specify the purpose of the
meeting; provided, however, that in case the 


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Board of Directors shall fix or change the time or place of any regular meeting,
notice of such action shall be given to each director who shall not have been
present at the meeting at which such action was taken within the time limit, and
in the manner set forth in paragraph (b) of Section 4 of this Article III, with
respect to special meetings, unless such notice shall be waived in the manner
set forth in paragraph (c) of such Section 4.

Section 3 - Special Meetings; Notice:

         (a) Special meetings of the Board of Directors shall be held whenever
called by the President or by one of the Directors, at such time and place as
may be specified in the respective notices or waivers of notice thereof.

         (b) Except as otherwise required by statute, notice of special meetings
shall be mailed directly to each director, addressed to him at his residence or
usual place of business, at least two (2) days before the day on which the
meeting is to be held, or shall be sent to him at such place by telegram, radio
or cable, or shall be delivered to him personally or given to him orally, not
later than the day before the day on which the meeting is to be held. A notice,
or waiver of notice, except as required by Section 8 of this Article III, need
not specify the purpose of the meeting.

         (c) Notice of any special meeting shall not be required to be given to
any director who shall attend such meeting without protesting prior thereto or
at its commencement, the lack of notice to him, or who submits a signed waiver
of notice, whether before or after the meeting. Notice of any adjourned meeting
shall not be required to be given.

Section 4- Chairman:

         At all meetings of the Board of Directors, the Chairman of the Board,
if any and if present, shall preside. If there shall be no Chairman, or he shall
be absent, then the President shall preside, and in his absence, a Chairman
chosen by the directors shall preside.

Section 5 - Quorum and Adjournments:

         (a) At all meetings of the Board of Directors, the presence of a
majority of the entire Board shall be necessary and sufficient to constitute a
quorum for the transaction of business, except as otherwise provided by law, by
the Certificate of Incorporation, or by these Bylaws.

         (b) A majority of the directors present at the time and place of any
regular or special meeting, although less than a quorum, may adjourn the same
from time to time without notice, until a quorum shall be present.



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Section 6 - Manner of Acting:

         (a) At all meetings of the Board of Directors, each director present
shall have one (1) vote, irrespective of the number of shares of stock, if any,
which he may hold.

         (b) Except as otherwise provided by statute, by the Certificate of
Incorporation, or by these Bylaws, the action of a majority of the directors
present at any meeting at which a quorum is present shall be the act of the
Board of Directors. Any action authorized, in writing, by all of the directors
entitled to vote thereon and filed with the minutes of the corporation shall be
the act of the Board of Directors with the same force and effect as if the same
had been passed by unanimous vote at a duly called meeting of the Board.

Section 7 - Vacancies:

         Any vacancy in the Board of Directors occurring by reason of an
increase in the number of directors, or by reason of the death, resignation,
disqualification, removal (unless a vacancy created by the removal of a director
by the shareholders shall be filled by the shareholders at the meeting at which
the removal was effected) or inability to act of any director, or otherwise,
shall be filled for the unexpired portion of the term by a majority vote of the
remaining directors, though less than a quorum, at any regular meeting or
special meeting of the Board of Directors called for that purpose.

Section 8 - Resignation:

         Any director may resign at any time by giving written notice to the
Board of Directors, the President or the Secretary of the corporation. Unless
otherwise specified in such written notice, such resignation shall take effect
upon receipt thereof, by the Board of Directors or such officer, and the
acceptance of such resignation shall not be necessary to make it effective.

Section 9 - Removal:

         Any director may be removed with or without cause at any time by the
affirmative vote of shareholders holding of record in the aggregate at least a
majority of the outstanding shares of the corporation at a special meeting of
the shareholders called for that purpose, and may be removed for cause by action
of the Board.

Section 10 - Salary:

         No stated salary shall be paid to directors as such for their services,
but by resolution of the Board of Directors, a fixed sum and expenses of
attendance, if any, may be allowed for attendance at each regular or special
meeting of the Board; provided, however, that nothing herein contained shall be
construed to preclude any director from serving the corporation in any other
capacity and receiving compensation therefor.


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Section 11 - Contracts:

         (a) No contract or other transaction between this corporation and any
other corporation shall be impaired, affected or invalidated, nor shall any
director be liable in any way by reason of the fact that any one or more of the
directors of this corporation is or are interested in, or is a director or
officer, or are directors or officers of such other corporation, provided that
such facts are disclosed or made known to the Board of Directors.

         (b) Any director, personally and individually, may be a party to or may
be interested in any contract or transaction of this corporation, and no
director shall be liable in any way by reason of such interest, provided that
the fact of such interest be disclosed or made known to the Board of Directors,
and provided that the Board of Directors shall authorize, approve or ratify such
contract or transaction by the vote (not counting the vote of any such director)
of a majority of a quorum, notwithstanding the presence of any such director at
the meeting at which such action is taken. Such director or directors may be
counted in determining the presence of a quorum at such meeting. This section
shall not be construed to impair or invalidate or in any way affect any contract
or other transaction which would otherwise be valid under the law (common,
statutory or otherwise) applicable thereto.

Section 12 - Committees:

         The Board of Directors, by resolution adopted by a majority of the
entire Board, may from time to time designate from among its members an
executive committee and such other committees, and alternate members thereof, as
they may deem desirable, each consisting of three (3) or more members, with such
powers and authority (to the extent permitted by law) as may be provided in such
resolution. Each such committee shall serve at the pleasure of the Board.

                              ARTICLE IV - OFFICERS

Section 1 - Number Qualifications, Election and Term of Office:

         (a) The officers of the corporation shall consist of a President, a
Secretary, a Treasurer, and such other officers including a Chairman of the
Board of Directors, and one (1) or more Vice-Presidents, as the Board of
Directors may from time to time, deem advisable. Any officer other than the
Chairman of the Board of Directors may be, but is not required to be, a director
of the corporation. Any two (2) or more offices may be held by the same person.

         (b) The officers of the corporation shall be elected by the Board of
Directors at the regular annual meeting of the Board following the annual
meeting of shareholders.

         (c) Each officer shall hold office until the annual meeting of the
Board of Directors next succeeding his election, and until his successor shall
have been elected and qualified, or until his death, resignation or removal.



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Section 2 - Resignation:

         Any officer may resign at any time by giving written notice of such
resignation to the Board of Directors, or to the President or the Secretary of
the corporation. Unless otherwise specified in such written notice, such
resignation shall take effect upon receipt thereof by the Board of Directors or
by such officer, and the acceptance of such resignation shall not be necessary
to make it effective.

Section 3 - Removal:

         Any officer may be removed, either with or without cause, and a
successor elected by a majority vote of the Board of Directors at any time.

Section 4 - Vacancies:

         A vacancy in any office by reason of death, resignation, inability to
act, disqualification, or any other cause, may at any time be filled for the
unexpired portion of the tem by a majority vote of the Board of Directors.

Section 5 - Duties of Officers:

         Officers of the corporation shall, unless otherwise provided by the
Board of Directors, each have such powers and duties as generally pertain to
their respective offices as well as such powers and duties as may be set forth
in these Bylaws, or may from time to time be specifically conferred or imposed
by the Board of Directors. The President shall be the chief executive officer of
the corporation.

Section 6 - Sureties and Bonds:

         In case the Board of Directors shall so require, any officer, employee
or agent of the corporation shall execute to the corporation a bond in such sum,
and with such surety or sureties as the Board of Directors may direct,
conditioned upon the faithful performance of his duties to the corporation,
including responsibility for negligence and for the accounting for all property,
funds or securities of the corporation which may come into his hands.

Section 7 - Shares of Other Corporations:

         Whenever the corporation is the holder of shares of any other
corporation, any right or power of the corporation as such shareholder
(including the attendance, acting and voting at shareholders' meetings and
execution of waivers, consents, proxies or other instruments) may be exercised
on behalf of the corporation by the President, any Vice-President, or such other
person as the Board of Directors may authorize.


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                           ARTICLE V - SHARES OF STOCK

Section 1 - Certificate of Stock:

         (a) The certificates representing shares of the corporation shall be in
such form as shall be adopted by the Board of Directors, and shall be numbered
and registered in the order issued. They shall bear the holder's name and the
number of shares, and shall be signed by (i) the Chairman of the Board or the
President or the Vice-President, and (ii) the Secretary or Treasurer, or any
Assistant Secretary or Assistant Treasurer, and shall bear the corporate seal.

         (b) No certificate representing shares shall be issued until the full
amount of consideration therefor has been paid, except as otherwise permitted by
law.

         (c) To the extent permitted by law, the Board of Directors may
authorize the issuance of certificates for fractions of a share which shall
entitle the holder to exercise voting rights, receive dividends and participate
in liquidating distributions, in proportion to the fractional holdings; or it
may authorize the payment in cash of the fair value of fractions of a share as
of the time when those entitled to receive such fraction are determined; or ir
may authorize the issuance, subject to such conditions as may be permitted by
law, of scrip in registered or bearer form over the signature of an officer or
agent of the corporation, exchangeable as therein provided for full shares, but
such scrip shall not entitle the holder to any rights of a shareholder, except
as therein provided.

Section 2 - Lost or Destroyed Certificates:

         The holder of any certificate representing shares of the corporation
shall immediately notify the corporation of any loss or destruction of the
certificate representing the same. The corporation may issue a new certificate
in the place of any certificate theretofore issued by it, alleged to have been
lost or destroyed. On production of such evidence of loss or destruction as the
Board of Directors in its discretion may require, the Board of Directors may, in
its discretion, require the owner of the lost or destroyed certificate, or his
legal representatives, to give the corporation a bond in such sum as the Board
may direct, and with such surety or sureties as may be satisfactory to the
Board, to indemnify the corporation against any claims, loss, liability or
damage it may suffer on account of the issuance of the new certificate. A new
certificate may be issued without requiring any such evidence or bond, when in
the judgment of the Board of Directors it is proper so to do.

Section 3 - Transfers of Shares:

         (a) Transfers of shares of the corporation shall be made on the share
records of the corporation only by the holder of record thereof, in person or by
his duly authorized attorney, upon surrender for cancellation of the certificate
or certificates representing such shares, with an assignment or power of
transfer endorsed thereon or delivered therewith, duly executed, with such proof
of the authenticity or the signature and of authority to transfer and of payment
of transfer taxes as the corporation or its agents may require.


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         (b) The corporation shall be entitled to treat the holder of record of
any share or shares as the absolute owner thereof for all purposes and,
accordingly, shall not be bound to recognize any legal, equitable or other claim
to, or interest in, such share or shares on the part of any other person,
whether or nor it shall have express or other notice thereof, except as
otherwise expressly provided by law.

Section 4 - Record Date:

         In lieu of closing the share records of the corporation, the Board of
Directors may fix, in advance, a date not exceeding fifty (50) days, nor less
than ten (10) days, as the record date for the determination of shareholders
entitled to receive notice of, or to vote at, any meeting of shareholders, or to
consent to any proposal without a meeting, or for the purpose of determining
shareholders entitled to receive payment of any dividends, or allotment of any
rights, or for the purpose of any other action. If no record date is fixed, the
record date for the determination of shareholders entitled to notice of or to
vote at a meeting of shareholders shall be at the close of business on the day
next preceding the day on which notice is given, or, if no notice is given, the
day on which the meeting is held; the record date for determining shareholders
for any other purpose shall be at the close of business on the day on which the
resolution of the directors relating thereto is adopted. When a determination of
shareholders of record entitled to notice or to vote at any meeting of
shareholders has been made as provided for herein, such determination shall
apply to any adjournment thereof, unless the directors fix a new record date for
the adjourned meeting.

                             ARTICLE VI - DIVIDENDS

         Subject to applicable law, dividends may be declared and paid out of
any funds available therefor, as often, in such amounts, and at such time or
times as the Board of Directors may determine.

                            ARTICLE VII - FISCAL YEAR

         The fiscal year of the corporation shall be fixed by the Board of
Directors from time to time, subject to applicable law.

                          ARTICLE VIII - CORPORATE SEAL

         The corporate seal, if any, shall be in such form as shall be approved
from time to time by the Board of Directors.


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                             ARTICLE IX - AMENDMENTS

Section 1 - By Shareholders:

         All bylaws of the corporation shall be subject to alteration or repeal,
and new bylaws may be made, by the affirmative vote of shareholders holding of
record in the aggregate at least a majority of the outstanding shares entitled
to vote in the election of directors at any annual or special meeting of
shareholders, provided that the notice or waiver of notice of such meeting,
shall have summarized or set forth in full therein, the proposed amendment.

Section 2 - By Directors:

         The Board of Directors shall have power to make, adopt, alter, amend
and repeal, from time to time, the bylaws of the corporation; provided, however,
that the shareholders entitled to vote with respect thereto as in this Article
IX above provided may alter, amend or repeal bylaws made by the Board of
Directors, except that the Board of Directors shall have no power to change the
quorum for meetings of shareholders or of the Board of Directors, or to change
any provisions of the bylaws with respect to the removal of directors or the
filling of vacancies in the Board resulting from the removal by the
Shareholders. If any bylaw regulating an impending election of directors is
adopted, amended or repealed by the Board of Directors, there shall be set forth
in the notice of the next meeting of shareholders for the election of directors,
the bylaw so adopted, amended or repealed, together with a concise statement of
the changes made.

                              ARTICLE X - INDEMNITY

         (a) Any person made a party to an action, suit or proceeding, by reason
of the fact that he, his testator or intestate representative is or was a
director, officer or employee of the corporation, or of any corporation in which
he served as such at the request of the corporation, shall be indemnified by the
corporation against the reasonable expenses, including attorney's fees, actually
and necessarily incurred by him in connection with the defense of such action,
suit or proceedings, or in connection with any appeal therein, except in
relation to matters as to which it shall be adjudged in such action, suit or
proceeding, or in connection with any appeal therein that such officer, director
or employee is liable for negligence or misconduct in the performance of his
duties.

         (b) The foregoing right of indemnification shall not be deemed
exclusive of any other rights to which any officer or director or employee may
be entitled apart from the provisions of this section.

         (c) The amount of indemnity to which any officer or any director may be
entitled shall be fixed by the Board of Directors, except that in any case where
there is no disinterested majority of the Board available, the amount shall be
fixed by arbitration pursuant to the then existing rules of the American
Arbitration Association.


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       ARTICLE XI - CERTIFICATE OF CORPORATION AND SHAREHOLDERS AGREEMENT

         Notwithstanding anything to the contrary, the provisions of the
Certificate of Incorporation and a Shareholders Agreement shall supersede any
conflicting provisions of these Bylaws and are hereby incorporated by reference
as part of these Bylaws.

               ARTICLE XII - REIMBURSEMENT OF DISALLOWED EXPENSES

         Any payments made to an Officer or Director of the Corporation such as
salary, commission, bonus, fees, interest, rent or entertainment expense
incurred by him, which shall be disallowed in whole or in part as a deductible
expense by the Internal Revenue Service, shall be reimbursed by such Officer of
the Corporation to the full extent of such disallowance. lt shall be the duty of
the Directors, as a Board, to enforce payment of each amount disallowed. In lieu
of payment by the Officer, subject to the determination of the Directors,
proportionate amounts may be withheld from his future compensation payments
until the amount owed to the Corporation has been recovered.

         IN WITNESS WHEREOF, the President of the corporation hereby executes
these Bylaws and certifies that these Bylaws are adopted by the corporation, as
of the 27th day of September, 1990 to replace the original Bylaws which have
been misplaced.


                                                     QUINCY JOIST COMPANY


                                            By:      /s/  E. C. Addison
                                                    --------------------------
                                                     E. C. ADDISON, Chairman


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