The Application Of PFWD In The Rapid Detection Of Subgrade Compaction Quality And Uniformity Evaluation

The random sampling methods which the traditional method of compactnessdetection use belongs to the point detection, these methods in addition to resulting inweak point leakage measurements, but also easyto damage the embankment structure.Aiming at the deficiency of compaction degree detection method, detection technologyof continuous compaction have began at home and abroad. Because PFWD has theadvantages of simple, fast, no damage and so on. If PFWD can be used to detect thecompactness in road construction, it could speed up the construction progress andshorten the construction period. It will play a great role in promoting the development inthe field.Through play laboratory experiments on sand soil, lime soil and gravel soil, weknow the relationship between the degree of compaction and dynamic deformationmodulus value(Evd), and we also studied the factors in influencing the quality ofcompaction. Then we take a series of field experiments to modify the results oflaboratory test.At the same time we put forward the Evd-values what is used to evaluatethe quality of compaction in subgrade. And then through the data acquisition andanalysis on the experimental section, we can judge the utility of the index we putforward.The uneven compaction of subgrade may lead to the uneven settlement ofSubgrade,This will not only reduce the flatness of the pavement structure, but alsoreduce the overall strength of the structure, and cause a variety of diseases on the road,eventually lead to the destruction of the whole pavement structure. Therefore, ascientific and reasonable evaluation on compaction uniformity of roadbed has a veryimportant meaning in subgrade engineering. In this regard, through consulting thedomestic and foreign research results, we put forward a method that combine"consistency statistics value of the data in the different lane-h" and "consistencystatistics value of the data in the same lane-k" and the Mathlab simulation to analyse thevertical and horizontal section uniformity of Subgrade. And then carry out the on-sitedata monitoring on the road from Qianfeng Farm to Nenjiang River, aiming at verifyingthe feasibility of the method. The results show that: this evaluation method has certainhelp to judge the compaction unreasonable regional s position, and canbe used to guidethe construction, and has a importantly practical significance.