1, subgrade construction:
During surveying and setting out and preliminary geotechnical test, a group of central piles should be set at intervals of 20~25m in the whole section during construction, and the pile points at the beginning, middle and end of the curve section should be well controlled. Geotechnical tests are carried out in soil sources to provide various test data for earthwork and subgrade construction. ?
In the test section, before the subgrade starts, the representative road section with the length not less than 100m is selected as the test section under the supervision engineer's side station for compaction test; And report the test results to the supervision engineer for approval.
After the subgrade is leveled, the trench under the subgrade shall be backfilled to below the subgrade elevation 15㎝, and the subgrade construction shall be carried out evenly to make the subgrade have better integrity.
Compacted and leveled packing layer shall be rolled by self-propelled vibratory roller. The rolling speed is 3 ~ 4 km/h. The water content is kept at the optimum water content.
2. Cushion construction?
After the completion of subgrade engineering, pavement engineering can implement one-stop operation of cushion construction, layered stacking, grader mixing and paving, roller rolling and sprinkler maintenance.
During the construction, the grading and uniformity of particles, the thickness, flatness and compactness of paving materials must be strictly controlled, and the curing work should be done in time. ?
Restore the center line on the soil subgrade. One pile is set every 15 ~ ~ 20m in straight line section, one pile every10 ~15 ~ ~ 20m in flat curve section, and indicator piles are set 0.3 ~ ~ 0.5m outside the shoulder edge on both sides. ?
Choose graded materials that meet the design requirements to prepare materials, and pile them evenly in layers on the subgrade according to the loose laying thickness. ?
Paving: Use a grader to spread the mixture evenly on a predetermined width according to the loose paving thickness, and the surface should be as flat as possible, with a specified road arch.
Shaping and rolling: use a tire roller to quickly roll on the initially leveled road section to expose potential unevenness, and then use a grader to level and shape.