EXHIBIT 3.42

                                                             F I L E D

                                                            JAN 24 1986

                                                                1 PM

                                                           /s/ Illegible
                                                         SECRETARY OF STATE


                          CERTIFICATE OF INCORPORATION

                                       OF

                            RIVERSIDE CEMENT COMPANY

                   1. The name of the corporation is:

                            RIVERSIDE CEMENT COMPANY

                   2. The address of its registered office in the State of
Delaware is Corporation Trust Center, 1209 Orange Street, in the City of
Wilmington, County of New Castle. The name of its registered agent at such
address is The Corporation Trust Company.

                   3. The nature of the business or purposes to be conducted or
promoted is to engage in any lawful act or activity for which corporations may
be organized under the General Corporation Law of Delaware.

                   4. The total number of shares of stock which the corporation
shall have authority to issue is One Thousand (1,000) and the par value of each
of such shares is One Dollar ($1.00) amounting in the aggregate to One Thousand
Dollars ($1,000.00).

                   5. The board of directors is authorized to make, alter or
repeal the bylaws of the corporation. Election of directors need not be by
written ballot.

                   6. The name and mailing address of the incorporator is:

                                            V. A. Brookens
                                            Corporation Trust Center
                                            1209 Orange Street
                                            Wilmington, Delaware 19801

             I, THE UNDERSIGNED, being the incorporator hereinbefore named, for
the purpose of forming a corporation pursuant to the General Corporation Law of
Delaware, do make this certificate, hereby declaring and certifying that this is
my act and deed and the facts herein stated are true, and accordingly have
hereunto set my hand this 24th day of January, 1986

                                            /s/ V. A. Brookens
                                            ------------------------------------
                                            V. A. Brookens