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                                  FORM 10-Q/A

                               (Amendment No. 1)
     
                       SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C.  20549

                              --------------------

         [X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

                 For the quarterly period ended March 31, 1997

                                       OR

         [ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

                 For the transition period from _____ to _____

                         Commission file number 1-5259

                              ____________________

                             PITT-DES MOINES, INC.
             (Exact name of registrant as specified in its charter)

         Commonwealth of Pennsylvania               25-0729430
       (State or other jurisdiction of           (I.R.S. Employer
       incorporation of organization)           Identification No.)

       3400 Grand Avenue, Pittsburgh, PA               15225
       (Address of Principal Executive Offices)     (Zip Code)

                                 (412) 331-3000
              (Registrant's Telephone Number, including Area Code)
                              ____________________

          Indicate by check whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.
Yes   X   No
    -----    ----    

          On March 31, 1997, 3,482,966 shares of Common Stock were outstanding.

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Item 6.  Exhibits and Reports on Form 8-K

    (a)  Exhibits

         Exhibit 11.1 - Computation of earnings per share for the three
         months ended March 31, 1997 and 1996.

         Exhibit 27 - Financial Data Schedule

    (b)  Reports on Form 8-K.
    
         A Form 8-K, dated January 31, 1997, was filed to report the Company's
         acquisition of General Steel Corporation, a steel service center,
         located in Vancouver, Washington. No financial statements were filed as
         part of the Form 8-K.
     


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                                  Signatures


Pursuant to the requirements of the Securities Exchange Act of 1934, the 
registrant has duly caused this report to be signed on its behalf by the 
undersigned thereunto duly authorized.



                                    Pitt-Des Moines, Inc.
                                    ----------------------------------
                                          (Registrant)




                                    Principal Financial Officer:

    
Date:  May 16, 1997                 By:  /s/ R. A. Byers
                                    ----------------------------------
                                             R. A. Byers
                                             (Vice President
                                             Finance and Treasurer)




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                                 EXHIBIT INDEX


Exhibit
Number
-------   
11.1        Computation of earnings per share for the three
               months ended March 31, 1997 and 1996

27          Financial Data Schedule



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