EXECUTION 3.1 General

A. In general, all construction methods shall conform to the applicable provisions of the Mass. SSHB, 1988 edition, unless specifically stated otherwise herein.

3.2 Installation

A. Gravel bases shall be prepared to receive bituminous concrete pavement by grading and rolling to the proposed subgrades. Wetting of the gravel may be required if necessary to maintain compac-tion and grading. Rolling shall be done with a roller weighting the same as specified for the pro-posed pavement. Crowning of the base gravel up to one inch will be required to provide for addi-tional trench settlement. Existing paved surfaces on which new pavement is to be placed shall be swept clean of all debris and loose materials.

B. All joints at existing pavement cuts, berms, roadway castings, etc. shall be tack coated prior to placement of new surfacing against them. Cut joints at existing and new top pavement surfaces shall be sealed with bitumen and sand. This includes roadways, sidewalks, driveways and all other pavements.

C. Cold patch when directed by the Owner shall be placed over the backfilled trenches and com-pacted by mechanical tamping or approved wheel rolling methods to provide a comcom-pacted depth of two inches. Prior to placing the cold patch, the backfill shall be graded to provide a one inch crown.

D. The Contractor shall be responsible for keeping the surface of all the patched trenches level with

E. Immediately upon satisfactory testing of the pipes, the Contractor shall recut the edges of the previously cut pavement damaged during excavation and backfilling and grade the previously placed gravel base courses to receive the specified thickness of Type I Bituminous Concrete pavement. Bituminous concrete patch shall match existing pavement at a minimum and shall in no case be less than two inch Binder Course and one inch Top Course. This material may be hand or machine placed within the trench to provide a one inch crown and the minimum compacted speci-fied thickness of pavement when rolled with an eight ton roller. Roadway castings within the trench shall be set to receive the final surfacing and be temporarily ramped for safety.

F. Sidewalks, driveways, walks and other miscellaneous bituminous paved surfaces disturbed by the work shall be replaced in as good a condition as existed prior to the work.

G. Existing public sidewalks shall be cut at right angles to their edges 12 inches beyond the nearest trench wall. The gravel base shall be fine graded and rolled. Type I bituminous concrete shall be placed in two, one inch layers, each layer being compacted with a roller weighing a minimum of three tons. Edges shall be straight uniform.

H. Driveways, if any, disturbed by the work shall be replaced to their existing thicknesses. Existing pavement shall be cut at right angles to edges and all joints shall be tack coated and sealed.

Where conditions warrant (short length, flat angle crossings, etc.), the Owner may require a one inch overlay over the entire driveway or a portion thereof.

I. Berms shall be machine formed to match existing configurations in long runs and may be hand formed in short runs (four feet or less).

J. Private walks shall be replaced to the existing depths and widths in segments determined by the Owner.

K. All work within MIT property shall be in accordance with the following requirements:

1. Cutting by mechanical means: all pavement surfaces shall be cut by an approved me-chanical means before any excavation is started to insure against unnecessary damage to pavement.

2. Excavation shall be done in a safe manner so as to create a minimum amount of obstruc-tion to pedestrian or vehicular traffic.

3. Backfilling Trenches: Suitable material of a stable nature shall be used and placed in six-inch layers and thoroughly compacted to 95% of the maximum dry density by mechanical means. Top 12 inches of backfill shall be compacted gravel.

4. Temporary Patch: All trenches shall be resurfaced with a temporary patch at the end of each working day with a minimum of thickness of three inches of bituminous concrete. This should be allowed to remain for a minimum period of 60 days, a maximum period of 90 days and be maintained by the Contractor. No permanent resurfacing shall be done without permission from the Owner. He shall be the sole agent to determine whether the trench is ready for permanent resurfacing. The Contractor shall be required to thoroughly clean all road surfaces at the end of each day.

5. Permanent Resurfacing:

a. All trenches shall be cut back one foot on each side from original cut by an approved mechanical means.

b. 12 inches of approved gravel placed in two layers and compacted by mechanical means to 95%.

c. Three inches of bituminous concrete placed in two layers of two inch binder and 1-1/2”

inch top and rolled with a powered roller having a weight of five tons or more. Existing pavements thicker than three inches shall be replaced to an equal thickness using materials as similar as possible to the existing (concrete, crushed stone with bitumi-nous concrete, etc.).

d. Before placing bituminous concrete, all joints shall be satisfactorily emulsified and again after placing top course of bituminous concrete, all joints shall be emulsified and sanded using screened sand.

6. Curbs shall be restored completely.

END OF SECTION