R2014-70 ACCEPTING THE BID & AUTHORIZING CONTRACT FOR STREET RESTORATION

Home Browse Search

CITY OF DECATUR SUPPLEMENTAL SPECIFICATIONS ' FOR SECTION 352: SOIL— CEMENT BASE COURSE 352.01 Description. Add the following to this Article: ' "The reconstruction work and the order in which it is conducted will be as follows: (1) Pulverizing and tilling the existing street surface and its base material to the required depth than compacting and removing excess material from the street to achieve final grade(Pay Item(s): Pulverize Shape And Compact, Earth Excavation). (2) Construction of the soil— cement base course (Pay Items: Cement, Processing Soil- Cement Base Course). (3) Cold mill the stabilized surface to level and provide the proper cross slope to the Soil- Cement base course prior to overlay(Pay Item: Shaping and Grading Roadway). ' Each street segment shall be reconstructed from initial pulverizing and tilling to final bituminous surfacing within 5 working days." 352.05 Proportioning. This Article will be deleted and the following inserted: "Proportioning Design. Prior to construction,the contractor shall, obtain samples as specified herein and prepare or have prepared soil-cement mix designs for approval by the Engineer. The existing pavement and base course will be sampled at locations designated by the Engineer for use in preparing a mix design for the soil-cement base course. At least two cores or test pits will be taken per section or block. In the event the samples show the existing pavement thickness to vary in excess of 1-inch and or the composition of the pavement material to vary substantially in the quality ' or content of aggregate and asphalt, the Engineer may direct additional samples to be collected. The samples shall be analyzed for gradation of aggregate, percent asphalt, and penetration of asphalt. Mix designs will be prepared for the soil-cement base course using the results from the analyses of the samples taken. A soil-cement mix design will be prepared recommending the application rate of cement to the used in the soil-cement base course to obtain a compressive strength of 300 pounds per square inch (psi). The design for the soil-cement base course will recommend the percent of cement to be added and the amount of aggregate base if required to fortify the base. The Marshall Stability value and the resulting maximum theoretical density shall be determined for the recommended mix design. For the purpose of assigning quantities for this project, the ratio per 100 lb. weight of cement per square yard was estimated at 10%. 352.07 Pulverizing. The first sentence of this Article is rewritten as follows: The street surface and base material shall be scarified, pulverized and mixed together to the ' depth of reconstruction prior to being shaped to the proper grade as specified in Article 352.06 and prior to application of the cement." 1