4/1/1958 - Laserfiche WebLink

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n LJ 1 1 0 1 1 1 0 2 roller until the feet of the roller walk out to within la inches of the surface. The graders shall be used in conjunction with the sheep's foot rollers to keep the mixture shaped to approximate plan and cross-section and also to keep the sheep's foot indentation in the mix - tune filled so that uniform action will be obtained. After compaction the surface shall then be shaped to line, grade and cross section allowing sufficient elevation of the mixture to compensate the final compaction. The mixture shall then be thoroughly rolled with a 8 ton tandem roller equipped with scrapers and oil sacks on the wheels to prevent picking up the material. Thickness determination shall be made as directed by the County Engineer. 0.4) Marl Base The material used shall either be a shell-iparl which in its original state is either in the loose stage or cemented, or a comparatively soft shell rock. The material shall be such as will not require crushing. The material shall be free from trash or other foreign matter. It shall not contain lumps or aggregate in sufficient quantity to prevent securing a smooth surface free from pits or pockets. When the material is excavated from water it shall be stock piled and allowed to dry out before being placed. The marl shall be approved by the engineer for use. No plastic material shall be used. All equipment necessary for the proper construction for this work shall be placed on the project, in first class working condition, and shall have been approved by the engineer before construction is started. No forms will be required unless specified. After the sub -grade has been compacted as specified in Section X -3(c), the base material shall be placed and spread over the sub -grade to such loose thickness as to insure that the finished base course will have the thickness required by the typical section. After spreading is completed the entire surface shall be scarified and shaped so as to pro- duce exact grade and cross section after compaction. When the material does not have the proper moisture contentto insure the required density, wetting or drying will be required. As soon as proper conditions of moisture are obtained the material shall be compacted to the satisfaction of the engineer and/or to an average density of at least 95% of the maximum den- sity obtainable under A.A.S.H.O. Method T99, at optimum moisture, or other approved methods. Unless otherwise directed by the engineer, the surface shall be (Hard planed) with a blade grader immediately prior to the application of the prime coat, to remove the thin glazed or cemented surface of the base. If at any time the sub -grade material should become mixed with the base course material, the contractor shall without additional compen- sation, dig out and remove the mixture, reshape and compact the sub -grade and replace the materials removed with clean base material, which shall be shaped and compacted as specified above. If cracks or checks appear in the base, either before or after priming, which, in the opinion of the engineer, would impair the structural efficiency of the base course, the con- tractor shall remove such cracks or checks by re -scarifying, reshaping, adding base material where necessary, and recompacting. The completed base course shall be open to the traffic for a sufficient period of time as determined by the engineer, to allow the base to become thoroughly cured before the