【作者】 苏晓科；

【导师】 俞晓；

【作者基本信息】 武汉科技大学 ， 采矿工程， 2005， 硕士

【摘要】 随着高层和高耸建筑物的发展,深基坑开挖支护技术的应用和研究日益重要,但是,由于深基坑工程的复杂性和不确定性,关于深基坑支护技术至今还未整理出一套系统的理论和设计方法,在设计和施工中还存在着很多的问题。在基坑工程设计方法发展的过程中,国内外学者都曾进行了较多的研究,包括室内模型试验、现场实测和理论探讨都有不同的进展。模型试验技术是研究和解决岩土工程问题的重要手段,在国内外已得到了广泛应用,并在工程科研、设计及论证中发挥了重要作用。其中室内模型试验相对要简单,可操作性强,可重复性高,能够很好的反应支护结构应力、变形和位移等各方面的相互关系。简要叙述了深基坑工程分析与计算中的有关问题,以悬臂式支护结构为例,介绍了基坑支护结构的设计计算方法,并分析了过去支护结构设计中存在的主要问题——对支护结构位移影响的考虑甚为欠缺。深基坑支护室内模型试验装置由主体试验架、模型箱、板桩墙模型及配套装置组成,主要用于非饱和土中基坑模拟开挖的室内试验研究,支护模型可以是悬臂式或拉锚式,并可用于锚杆的受力分析。试验装置首次运用微型高频土压力传感器测量模型板上土压力,测试结果更加精确。介绍了板桩墙支护系统的设计和制作过程,特别是减摩装置和止砂措施,成功的解决了模型板自由位移和开挖过程中的漏砂问题。另外,还讨论了位移测试系统和加载装置,由YS-1型高压固结仪加工改装的加载装置轻巧灵便,易于调整,能够很好的控制加载大小。最后,运用该装置进行基坑模拟开挖的试验,主要介绍了试验的准备工作、试验设计和试验目的,并给出了详细的试验步骤,以供参考,初步研究了支护侧土体位移和模型板位移及土压力的变化情况。试验过程和结果表明该装置设计合理、效果理想,能够运用于对岩土工程模型的室内试验研究。更多还原

【Abstract】 With the development of high and towering building, the application and study of the deep-foundation pit excavation supporting technology becomes more and more important. However it has not have a systemic theory and design method about the deep-foundation pit engineering because of its complexity and uncertainty. It exists a lot of problems in designing and constructing. The scholar of inside and outside did a lot of study in the development of foundation pit engineering design method, including indoor model tests, road-test and theory discussion. Model test method is an important way to research and solve the problem of geotechnical engineering; it applied comprehensively at home and aboard, it also exerted important effect in scientific research, design and argumentation of engineering. Therein to, the indoor model test has good maneuverability, high repeat at relatively, and it’s can response correlations of stress, deformation and displacement about the supporting structures. It’s much easier than others. This essay depict some knowledge about analyze and compute of the deep-foundation pit engineering briefly. It introduced the design and compute method of support structures as cantilever support structures for example, and analyzed the main question of support structures design in the past, the short of consideration to support structures’ displacement influence. The deep-foundation pit supporting indoor model tests device is composed of main test frame, test box, sheet pile wall and accessory devices. It can be used in indoor test of foundation pit simulate excavation with unsaturated soil and stress analysis of the anchor, the support models is cantilever or anchored. It is the first time used the mini soil pressure sensor to measure soil pressure in the model tests and the result is more exactly. Introduce the design and manufacture process of sheet pile wall support system, especially the decrease friction device and obstruct sand way, it resolved the freedom displacement of sheet pile wall and problem of leak sand in the excavation process successfully. On the other side, it also discussed the displacement test systems and the load device which refit by high-pressure consolidation apparatus YS-1 is legerity, maneuverable and in a position to control the load. In the end, it introduced how to do the test of foundation pit simulate excavation with this device, mostly introduce the preparative work, the design and the purpose, and the detailed test step are given to be referenced. It pilot studies the transformation of soil mass displacement of support side, model board displacement and soil pressure. The process and result of the test show that it’s reasonable to design, this set it can be used in studying the indoor tests in the model of geotechnical engineering.更多还原