Study On Dynamic Compaction Test Of High Filled Foundation In Mountain Areas And Performance Of Reinforced Retaining Wall

In recent years, with the continuous expansion of the project construction scale, in order to protect the environment and conservation of land, more and more projects (such as power plants, substations, petrochemical and airport engineering) located in mountainous or hilly areas. Most of the foundations of these projects are high filled foundations, which will be faced with a lot of earthwork backfilling work. Because of the advantages of cost-effective, simple construction and apparent ground treatment effect, dynamic compaction method is often used to deal with high filled foundation to improve the strength and bearing capacity, reduce the compression and improve the heterogeneity of the backfill foundation. High slope or reinforced retaining wall is often the products of the high filled foundation, so studying the performance of the reinforced retaining wall and the influence by dynamic compaction has great practical significance and engineering value.In this paper, based on a UHV substation projects of high filled foundation, some specific questions were studied during dynamic compaction for high filled foundation. Analyzing the attenuation rule of dynamic compaction vibration and influence to reinforced retaining wall by it, and some specific measures for prevention of dynamic compaction vibration were advanced. The main contents as follows:1. Introducing some commonly used methods for high filled foundation, and putting forward the superiority of dynamic compaction. The basic principles of the dynamic compaction/replacement and reinforced retaining wall were elaborated.2. The tests of dynamic compaction/replacement were carried out, according to the results of the tests, the suitable construction parameters and techniques were selected.3. According to the basic principles and advantages and disadvantages of various testing methods for dynamic compaction foundation, discussing the possibility of using a variety of testing methods for dynamic compaction foundation in a large area of mountains backfilled with gravel soils. Based on the large number of testing results, the relationships among bearing capacity characteristic value, deformation modulus, shear wave velocity and the blow counts of dynamic penetration were fitted by principles of statistics.4. Based on the field test and finite element simulation of dynamic compaction vibration, the attenuation rule of dynamic compaction vibration and the influence to reinforced retaining wall by dynamic compaction vibration were studied. The safety distance of dynamic compaction and measures of controlling dynamic compaction vibration were discussed.5. Based on the internal force monitoring tests of geogrids in reinforced retaining wall and finite element analysis, the variation of internal force of geogrids and the failure surface trends of reinforced retaining wall were studied.