Compaction Technology Of Highway Roadbed Widening Project

With the development of highway construction and the traffic flow is increasing, some high-grade highway can not meet the requirements of the development any longer. The basic solution is widening the existing road. But the widening road cracked and subgrade unstable early. The service life of the road are less than the design. Compaction did not go far enough is the root cause. Therefore the principal means to solve this problem is using effective compaction technology and its new detection method.Settlement of new-old roadbed and combination treatment of new-old roadbed have been the key technical issue, which relate to the use of the old roadbed. The dealing with science of them relate to the stability of the roadbed and have a direct impact on the life of the pavement structure. Traditional Compaction-Technology is the combination of static compaction and vibrating compaction. To avoid waste or compacted inadequate, and give full play to the role of compaction equipment, test section should be compacted for try. For widening roadbed project, how to use the existing old embankment effectively, reduce the cost and construction period, have been a concerned problem to people. In this paper, the combination treatment of new-old roadbed adopt impact compaction and dynamic compaction, which greatly reduce the above problem happened, use the old roadbed efficiently, saved a lot of money and shorten the construction period.In this paper, the measured laboratory test roadbed filling the physical and mechanical parameters of soil, analysis of the compaction process has been the static and vibration to optimize the combination of RCC, in view of the specificity of Subgrade widening, the use of impact in the test section and dynamic compaction to make the new roadbed to accelerate the settlement, the settlement reduces the difference between the old and the new roadbed. In this paper, through large number of on-site test and laboratory test, mechanics parameters of filling subgrade soil is measured, through on-site compaction test, static compaction and vibrating compaction is combined optimally, then impact compaction is carried out on them in order to increase soil strength and ensure roadbed more stable. On new-old roadbed combination, using dynamic compaction to ensure compaction up to standard. Simple penetration test is used as detecting method of compaction in whole process of compaction, at same time on-site detection also used as contrast test, and finally empirical formula between compaction and the value of simple penetration test is obtained, which is used to guide the compaction detecting in similar projects.