【作者】 黄磊；

【导师】 龚晓南；

【作者基本信息】 浙江大学 ， 建筑与土木工程（专业学位）， 2013， 硕士

【摘要】 近年来,随着工程建设规模的不断扩大,越来越多的工程(如电厂、变电站、石化和机场等工程)选址在山地或丘陵地带,以保护环境和节约用地。这些工程的地基大部分为高填方地基,将要面临着大量的土方回填工作。由于强夯法具有经济高效、施工简单、地基处理效果明显等优点,因而常被用来处理高填方地基,从而提高地基土的强度和承载力,降低地基土的压缩性,改善回填地基的不均匀性。高边坡或加筋土挡墙往往会伴随高填方地基的产生而产生,因而研究加筋土挡墙的工作性能及强夯振动对加筋土挡墙的影响具有重大的现实意义和工程价值。本文以某特高压变电站新建工程高填方地基为依托,对强夯加固高填方地基中的一些具体问题进行了分析,研究了强夯振动的衰减规律及强夯振动对加筋土挡墙的影响,提出了防治强夯振动的具体措施,主要内容有：1.介绍了常用的高填方地基处理方法,提出了强夯法的优越性。阐述了强夯(置换)加固地基原理和加筋土挡墙原理。2.分别开展强夯置换试验和回填土强夯试验,根据地基加固结果对强夯(置换)施工参数和施工工艺进行优化选择。3.分析了山区高填方强夯地基常用的几种检测手段的基本原理和优缺点,在此基础上,探讨了综合采用多种检测手段在大面积山区回填碎石土强夯地基中检测的可能性,并根据大量的检测试验结果,运用统计学原理分析了地基承载力特征值、变形模量、剪切波速和动力触探击数之间的相关性。4.根据现场强夯振动试验和有限元模拟结果,分析了强夯振动的衰减规律及其强夯对加筋土挡墙位移场的影响,提出了强夯施工的安全距离和防治强夯振动的措施。5.根据现场加筋土挡墙土工格栅内力监测和有限元分析结果,分析了土工格栅内力的变化规律,提出了加筋土挡墙潜在破坏面的发展趋势。更多还原

【Abstract】 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.更多还原