模袋注浆桩试验研究及其在软土路基中的应用

发布时间：2018-12-27 14:17

【摘要】：常规袖阀管注浆和高压旋喷注浆是公路软基病害的常见处治方法。常规袖阀管注浆注浆范围难以控制，难以形成连续桩体；高压旋喷注浆挤土效应过大、浆液流失。针对这些常见处治方法的不足，工程人员提出了模袋注浆技术，该技术通过设置模袋和塑料排水板等方式，较好地解决了上述问题。然而，模袋注浆技术目前仅有为数不多的应用实例，关于其成桩机理、挤土效应、设计计算方法等问题，尚未有系统的研究成果。鉴于其对公路软基病害处治的优点和适用性，对其作进一步的深入研究具有较高的工程价值和社会意义。本研究在分析模袋注浆技术研究现状的基础上，基于二广高速大旺互通A匝道出口试验工程和临海高等级公路连云港段二期路面工程，将模袋注浆技术分别与常规袖阀管注浆技术和高压旋喷注浆技术做了对比试验。采用试验与理论分析相结合的方法，对模袋注浆技术的施工参数、挤土效应、设计计算方法等几个方面进行了探讨，并对汕梅高速和江门—新会过境公路两项工程应用实例进行了分析，最后对模袋注浆技术在公路软基病害处治中的应用作出了综合评价。主要的工作有：开展模袋注浆桩与常规袖阀管注浆桩的现场对比试验，通过对施工期间注浆压力、孔隙水压力、周围土层侧向位移的观测，和施工后的抽芯、桩头开挖检测，比较了两种工法在施工过程中和施工后对地基土扰动的程度与影响范围及两者各自的加固效果。开展模袋注浆桩与高压旋喷桩的现场对比试验，通过对施工期间注浆压力、孔隙水压力、周围土层侧向位移的观测，比较了两种工法在施工过程中和施工后对地基土扰动的程度与影响范围及两者各自的加固效果。在分析模袋注浆桩成桩机理的基础上，参考水泥搅拌桩的设计计算方法，依据我国现行的相关规范，针对模袋注浆桩的特点，，提出了模袋注浆桩单桩沉降、单桩竖向承载力、模袋注浆桩加固路基稳定和模袋注浆桩复合地基沉降等计算方法。结合模袋注浆桩在汕梅高速K32+490通道桥桥头路段加固工程和省道S364江门、新会过境公路K2+932桥头路段加固工程这两项工程实例中的应用，对模袋注浆桩在公路软基加固的工程效果进行了分析。研究结果表明，模袋注浆桩的成桩质量较好，挤土效应介于常规袖阀管注浆桩和高压旋喷桩之间，注浆产生的超静孔压消散较快。实际工程应用表明，模袋注浆桩加固既有公路软基的效果较好。希望本次研究结果可为模袋注浆桩在今后相关工程中的推广和应用提供有价值的参考。
[Abstract]:Conventional sleeve valve pipe grouting and high pressure rotary grouting are common treatment methods for highway soft foundation diseases. It is difficult to control the grouting range of conventional sleeve valve tube and form continuous pile body. In view of the shortcomings of these common treatment methods, engineers put forward the grouting technology of mould bag, which solved the above problems better by setting mould bag and plastic drainage board. However, at present, there are only a few examples of application of mould bag grouting technology. There are no systematic research results on the mechanism of pile formation, soil squeezing effect, design and calculation method, etc. In view of its advantages and applicability to the treatment of highway soft foundation diseases, it is of high engineering value and social significance to further study it. On the basis of analyzing the present situation of the research on the grouting technology of mould bag, this study is based on the exit test project of A ramp of Erguang Expressway Dawang Interchange and the second phase pavement engineering of Lianyungang section of Linhai high grade highway. A comparative test was made between the bag grouting technology and the conventional sleeve valve grouting technology and the high pressure rotary jet grouting technology. By combining test with theoretical analysis, the construction parameters, soil squeezing effect, design and calculation methods of mould bag grouting technology are discussed. The application examples of Shanmei Expressway and Jiangmen-Xinhui Transit Highway are analyzed. Finally, the application of mould bag grouting technology in the treatment of soft foundation diseases of highway is comprehensively evaluated. The main works are as follows: to carry out the field comparative test between the mold bag grouting pile and the conventional sleeve valve pipe grouting pile, through the observation of grouting pressure, pore water pressure, lateral displacement of surrounding soil layer during construction, and the core pulling after construction, In this paper, the degree and influence range of the disturbance to the foundation soil during and after the construction of the two methods are compared, and the reinforcement effects of the two methods are compared. The field comparative test of the grouting pile with the high pressure rotary grouting pile was carried out, and the grouting pressure, pore water pressure and lateral displacement of the surrounding soil layer were observed during the construction period. The degree of disturbance and the influence range of the two methods on the foundation soil during and after construction are compared and their respective reinforcement effects are compared. On the basis of analyzing the forming mechanism of mould bag grouting pile, referring to the design and calculation method of cement mixing pile, according to the relevant codes of our country, according to the characteristics of mould bag grouting pile, the settlement of single pile and the vertical bearing capacity of single bag grouting pile are put forward. The calculation methods of stability of roadbed and settlement of composite foundation of mould bag grouting pile are presented. Combined with the application of moulded bag grouting pile in the reinforcement project of bridge-head section of Shan-Mei high-speed K32490 channel bridge and the reinforcement project of S364 Jiangmen section of provincial highway and K2932 bridgehead section of Xinhui transit highway, the application of the pile is discussed. In this paper, the effect of grouting pile in soft foundation of highway is analyzed. The results show that the pile quality is good, the compaction effect is between the conventional sleeve valve grouting pile and the high pressure rotary grouting pile, and the super-static pore pressure caused by the grouting dissipates faster. The practical engineering application shows that the grouting pile with mold bag is effective in strengthening the soft foundation of existing highway. It is hoped that the results of this study can provide a valuable reference for the popularization and application of mould bag grouting pile in related projects in the future.
【学位授予单位】：广州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

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