4/1/1958 - Laserfiche WebLink

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l exercised to overcome any tendency for the base in the vicinity of a junction between runs to I fail to be full thickness and true to grade or to be inadequately compacted, improperly pro- portioned, inadequately wetted, or incompletely mixed. When any of these operations, after I the application of cement, are interrupted for more than two hours for any reason, or when the uncompacted soil cement mixture is wetted by rain so that the required moisture content is lost, the entire section shall be reconstructed, except that the quantity of cement to be B added to the previously processed soil cement mixture shall be 50% of the amount originally i� specified. No cement shall be applied unless the temperature is at least 40 degrees F. and ris- ing. Immediately after compacting and finishing, the completed base shall be covered and protected against rapid drying either by an approved method of earth curing or by a bituminous seal coat. Thickness determination shall be made as directed by the County Engineer. (d.3) Mixed in place base. This base course shall be composed of a compacted mixture of 60% mineral aggregate and 40% marl (excluding plastic material) or shell material together with asphaltic material. The constituents of the mixed in place base shall be combined in such proportions` that after complete mixing, the resultant mixture shall be homogeneous and all particles i coated with bituminous material. The exact quantity of bituminous material shall be determined';, by the engineer during the operations of applying and mixing and will depend upon the character!,# and grading of the aggregate material. The proportions shall be varied, as directed by the engineer, after laboratory tests and field trials are conducted. The quantity of bituminous material shall be approximately 0.3 to 1.3 gallons per square yard per inch of compacted thickness. Unless otherwise specified and approved, the bituminous material shall be cut back asphalt grade RC -1S. All equipment necessary for the proper construction of this work shall be on the project, in first class working condition, and shall have been approved by the engineer before construction is started. Unless.otherwise approved a Seaman Mixer or a P&H Mixer shall be used to mix the material in place and a sheep's foot roller., or other approved types & methods, shall be used for compaction. If in place material is to become a portion of the base course the amount to be used must be wind rowed and the sub -grade prepared as described in Section X -3(c). All base course material shall have all roots and foreign matter removed to the satisfaction of the engineer. After the placing of the base material it shall be machined with the grader until a uniformity of line and grade has been obtained as determined by the engineer. No bituminous material shall be applied when the moisture content of the aggregate material is greater than 5% by weight, unless otherwise specified by the engineer. No application of bituminous material, mixing, spreading or finishing shall be done when the air temperature is less than 50 degrees F., or when in the opinion of the engineer the weather condition or the condition of the aggregate material is unsuitable. After mixing has been completed the mixture shall be cured until it has reached the proper consistency to be compacted. The mixture shall first be rolled with the sheep's foot 1 1 0 1 0 1 1