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                                                                     Exhibit 4.1


                                                                [EXECUTION COPY]


                               SECOND AMENDMENT TO
                              THE CREDIT AGREEMENT


         This SECOND AMENDMENT, dated as of June 26, 1998 (this "AMENDATORY
AGREEMENT"), to the Existing Credit Agreement (as defined below), is made among
DAYTON SUPERIOR CORPORATION, an Ohio corporation (the "BORROWER"), the various
financial institutions signatories hereto as Revolving Lenders (the "REVOLVING
LENDERS"), DLJ CAPITAL FUNDING, INC., as syndication agent (the "SYNDICATION
AGENT"), BANK OF AMERICA NATIONAL TRUST AND SAVINGS ASSOCIATION, as
documentation agent (the "DOCUMENTATION AGENT"), BANKERS TRUST COMPANY, as
administrative agent (the "ADMINISTRATIVE AGENT") and BANK ONE, N.A., as
facility agent (the "FACILITY AGENT").


                              W I T N E S S E T H:
                              - - - - - - - - - -

         WHEREAS, the Borrower, the Lenders, and the Agents are parties to a
Credit Agreement, dated as of September 29, 1997, as amended by Amendment No. 1
thereto (as so amended, the "EXISTING CREDIT AGREEMENT");

         WHEREAS, the Borrower has requested that the Revolving Lenders amend
the Existing Credit Agreement in certain respects; and

         WHEREAS, the Revolving Lenders have agreed, subject to the terms and
conditions hereinafter set forth, to amend the Existing Credit Agreement in
certain respects as provided below (the Existing Credit Agreement, as so amended
by this Amendatory Agreement, being referred to as the "CREDIT AGREEMENT");

         NOW, THEREFORE, in consideration of the agreements herein contained,
the parties hereto agree as follows:


                                     PART I
                                   DEFINITIONS

         SUBPART I.1. CERTAIN DEFINITIONS. The following terms (whether or not
underscored) when used in this Amendatory Agreement shall have the following
meanings (such meanings to be equally applicable to the singular and plural form
thereof):
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         "ADMINISTRATIVE AGENT" is defined in the PREAMBLE.

         "AMENDATORY AGREEMENT" is defined in the PREAMBLE.

         "AMENDMENT NO. 2" is defined in SUBPART 3.1.

         "BORROWER" is defined in the PREAMBLE.

         "CREDIT AGREEMENT" is defined in the THIRD RECITAL.

         "DOCUMENTATION AGENT" is defined in the PREAMBLE.

         "EXISTING CREDIT AGREEMENT" is defined in the FIRST RECITAL.

         "FACILITY AGENT" is defined in the PREAMBLE.

         "SECOND AMENDMENT EFFECTIVE DATE" is defined in SUBPART 3.1.

         "REVOLVING LENDERS" is defined in the PREAMBLE.

         "SYNDICATION AGENT" is defined in the PREAMBLE.

         SUBPART I.2. OTHER DEFINITIONS. Terms for which meanings are provided
in the Existing Credit Agreement are, unless otherwise defined herein or the
context otherwise requires, used in this Amendatory Agreement with such
meanings.


                                     PART II
                                AMENDMENTS TO THE
                            EXISTING CREDIT AGREEMENT

         Effective on (and subject to the occurrence of) the Second Amendment
Effective Date, the Existing Credit Agreement is hereby amended in accordance
with this Part II. Except as so amended, the Existing Credit Agreement shall
continue in full force and effect in accordance with its terms.

         SUBPART II.1. AMENDMENTS TO SECTION 1.1. Section 1.1 of the Existing
Credit Agreement is hereby amended by inserting the following definitions in
such Section in the appropriate alphabetical sequence:


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         "AMENDMENT NO. 2" means the Second Amendment to the Credit Agreement,
dated as of June 26, 1998, among the Borrower, the Revolving Lenders signatory
thereto, and the Agents.

         "SECOND AMENDMENT EFFECTIVE DATE" is defined in Subpart 3.1 of
Amendment No. 3.

         SUBPART 2.2. Clause (b) of Section 7.2.4 of the Existing Credit
Agreement is hereby amended to read in its entirety as follows:

                  (b) FIXED CHARGE COVERAGE RATIO. The Borrower will not permit
         the Fixed Charge Coverage Ratio as of the end of any Fiscal Quarter to
         be less than the ratio of 1.30:1; PROVIDED, that for purposes of
         computing the Fixed Charge Coverage Ratio for any period commencing
         with the Fiscal Quarter ending June 30, 1998, "CAPITAL EXPENDITURES"
         shall not include any expenditures for the purchase of Rental Equipment
         made during such period which, in accordance with GAAP, would be
         classified as capital expenditures.

         SUBPART 2.3. Section 7.2.7 of the Existing Credit Agreement is hereby
amended to read in its entirety as follows:

                  SECTION 7.2.7. CAPITAL EXPENDITURES, ETC. The Borrower will
         not, and will not permit any of its Subsidiaries to, make or commit to
         make Capital Expenditures in any Fiscal Year, except Capital
         Expenditures which do not aggregate in excess of 8% of the total
         consolidated revenues of the Borrower and its Subsidiaries for the
         immediately preceding Fiscal Year (with the revenues of any Subsidiary
         of the Borrower acquired during such Fiscal Year to include all
         revenues of such Subsidiary for the portion of such Fiscal Year
         preceding such acquisition); PROVIDED, HOWEVER, that to the extent the
         amount of Capital Expenditures permitted to be made in any Fiscal Year
         pursuant to this Section exceeds the aggregate amount of Capital
         Expenditures actually made during such Fiscal Year, up to 50% of such
         excess amount may be carried forward to (but only to) the next
         succeeding Fiscal Year (any such amount to be certified by the Borrower
         to the Agents in the Compliance Certificate delivered for the last
         Fiscal Quarter of such Fiscal Year, and any such amount carried forward
         to a succeeding Fiscal Year shall to be deemed to be used prior to the
         Borrower and its Subsidiaries using the amount of Capital Expenditures
         permitted by this Section without giving effect to such carry-forward).

         SUBPART 2.4. Clause (c) of Section 7.2.9 of the Existing Credit
Agreement is hereby amended to read in its entirety as follows:

                  (c) so long as no Default has occurred and is continuing or
         would occur after giving effect thereto, the Borrower or any of its
         Subsidiaries may purchase all or 

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         substantially all of the assets of any Person, or acquire such Person
         by merger, if permitted (without duplication) by SECTION 7.2.5 to be
         made as an Investment.

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                                    PART III
                           CONDITIONS TO EFFECTIVENESS

         SUBPART III.1. SECOND AMENDMENT EFFECTIVE DATE. This Amendatory
Agreement (and the amendments and modifications contained herein) shall become
effective, and shall thereafter be referred to as "AMENDMENT NO. 2", on the date
(the "SECOND AMENDMENT EFFECTIVE DATE") when all of the conditions set forth in
this SUBPART 3.1 have been satisfied.

         SUBPART III.1.1. EXECUTION OF COUNTERPARTS. The Facility Agent shall
have received counterparts of this Amendatory Agreement, duly executed and
delivered on behalf of the Borrower and each of the Required Revolving Lenders.

         SUBPART III.1.2. EXECUTION OF LOAN DOCUMENTS, ETC. The Facility Agent
shall have received counterparts of a supplement to the Subsidiary Guaranty and
a supplement to the Subsidiary Security Agreement, duly executed and delivered
by Concrete Accessories, Inc. and the Facility Agent, together with (i)
certificates representing all of the issued and outstanding shares of Capital
Stock of Concrete Accessories, Inc. owned by the Borrower, along with undated
stock powers for such certificates, executed in blank, and (ii) acknowledgment
copies of Uniform Commercial Code financing statements executed and delivered by
Concrete Accessories, Inc., as debtor, and the Facility Agent, as secured party,
filed under the UCC in all jurisdictions necessary or, in the reasonable opinion
of the Agents, desirable to perfect the security interest of the Facility Agent
pursuant to the Subsidiary Security Agreement.

         SUBPART III.1.3. LEGAL DETAILS, ETC. All documents executed or
submitted pursuant hereto shall be satisfactory in form and substance to the
Agents and their counsel. The Agents and their counsel shall have received all
information and such counterpart originals or such certified or other copies or
such materials, as the Agents or their counsel may reasonably request, and all
legal matters incident to the transactions contemplated by this Amendatory
Agreement shall be satisfactory to the Agents and their counsel.


                                     PART IV
                                  MISCELLANEOUS

         SUBPART IV.1. CROSS-REFERENCES. References in this Amendatory Agreement
to any Part or Subpart are, unless otherwise specified or otherwise required by
the context, to such Part or Subpart of this Amendatory Agreement.

         SUBPART IV.2. LOAN DOCUMENT PURSUANT TO EXISTING CREDIT AGREEMENT. This
Amendatory Agreement is a Loan Document executed pursuant to the Existing Credit
Agreement and shall be construed, administered and applied in accordance with
all of the terms and provisions of the Existing Credit Agreement.

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         SUBPART IV.3. COMPLIANCE WITH WARRANTIES, NO DEFAULT, ETC. The Borrower
represents and warrants on the Second Amendment Effective Date for its
Subsidiaries and itself, both before and after giving effect to this Amendatory
Agreement, as follows:

                  (a) the representations and warranties set forth in Article VI
         of the Credit Agreement (excluding those contained in Section 6.7
         thereof) and in each other Loan Document are, in each case, true and
         correct in all material respects (unless stated to relate solely to an
         earlier date, in which case such representations and warranties were
         true and correct in all material respects as of such earlier date);

                  (b) no adverse development has occurred in any litigation,
         action, proceeding, labor controversy, arbitration or governmental
         investigation disclosed pursuant to Section 6.7 of the Credit Agreement
         which could reasonably be expected to have a Material Adverse Effect;

                  (c) the sum of (A) the aggregate outstanding principal amount
         of all Revolving Loans and (B) the aggregate amount of all Letter of
         Credit Outstandings does not exceed the lesser of (c) the Revolving
         Loan Commitment Amount and (y) the Borrowing Base Amount; and

                  (d) no Default has occurred and is continuing, and neither the
         Borrower, any other Obligor, nor any of its Subsidiaries are in
         material violation of any law or governmental regulation or court order
         or decree.

         SUBPART IV.4. SUCCESSORS AND ASSIGNS. This Amendatory Agreement shall
be binding upon and inure to the benefit of the parties hereto and their
respective successors and assigns.

         SUBPART IV.5. COUNTERPARTS. This Amendatory Agreement may be executed
by the parties hereto in several counterparts, each of which when executed and
delivered shall be deemed to be an original and all of which shall constitute
together but one and the same agreement.

         SUBPART IV.6. GOVERNING LAW. THIS AMENDATORY AGREEMENT SHALL BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF
NEW YORK.

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         IN WITNESS WHEREOF, the parties hereto have caused this Amendatory
Agreement to be executed by their respective officers thereunto duly authorized
as of the day and year first above written.

                                     DAYTON SUPERIOR CORPORATION


                                     By:
                                        ----------------------------------------
                                        Title:



                                     BANK ONE,  N.A., as Facility Agent and a
                                     Revolving Lender


                                     By:
                                        ----------------------------------------
                                        Title:



                                     BANK OF AMERICA NATIONAL TRUST AND 
                                     SAVINGS ASSOCIATION, as
                                     Documentation Agent and a Revolving Lender


                                     By:
                                        ----------------------------------------
                                        Title:



                                     NATIONAL CITY BANK OF DAYTON, as
                                     a Revolving Lender


                                     By:
                                        ----------------------------------------
                                        Title:


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                                     DLJ CAPITAL FUNDING, INC., as
                                     Syndication Agent


                                     By:
                                        ----------------------------------------
                                        Title:



                                     BANKERS TRUST COMPANY, as
                                     Administrative Agent


                                     By:
                                        ----------------------------------------
                                        Title: