These specifications is for the construction of new existing roads by in–situ stabilization of road base layer with Chemroad and Cement. Cover all the work in connection to the stabilization of soil road base and include the scarifying of the in-situ soil road base, supply, mix the road base with cement, and the mixture of Chemroad and water, compact and cure the stabilized road base to the width and thickness shown on the drawing and to the tolerances specified herein.

The contractor shall have good experience in work involving in- situ stabilization and recycling of road. The work shall be supervised by a qualified and experienced soil stabilization engineer.

MATERIAL

1. Soil

a. These materials are normally aggregates and soil. The aggregates and soil shall be Crushed rock, gravel, milled asphalt concrete, laterite, coarse sand, or combination of these materials.

b. Soil classification when tested in accordance with AASHTO T 27-70, AASHTO T.89 and AASHTO T90 Should be A-1 a, A-2 and A-3 group (AASHTO classification)

c. Maximum nominal size aggregate is limited to 50 mm.

d. Liquid Limit when tested in accordance with AASHTO T89 should be less than 40

e. Plastic Index when tested ,in accordance with AASHTO T90 should be less than 15

f. L.A Abrasion loss when test in accordance with ASTM C131 should be less than 60

2. Cement

The cement should be ordinary setting Portland cement complying with ASTM C150. Cement delivered to the size should be fresh or test to be fresh.The cement shall be used within a reasonable period after delivery. Dry storage should be provided for cement that is not used immediately upon delivery to the size.

3. Cement–Road

The objectives of Chemroad soil cement stabilization are.

a. To minimize the damage to the road surface caused by cracking/settlement of subgrade appearing as reflective cracking, rutting and pot hole.

b. To provide a waterproofing effects so as to increase the durability of the road by Reducing the rate of saturation of the sub-base/base.

c. To provide a more flexible pavement wherein a reduction in stiffness can be achieved without a decrease in strength.

d. To allow for pavement to rebound upon of load and there increase the resistance against rutting.