【作者】 周裕利；

【导师】 张四平； 吴曙光；

【作者基本信息】 重庆大学 ， 岩土工程， 2010， 硕士

【摘要】 目前,桩锚支护体系由于其安全可靠、经济适用等优点,已广泛应用于高陡边坡、深基坑支护等工程当中,在岩土工程领域获得了较大的发展。压力型锚杆(索)作为较新型锚杆,由于其优良的锚固性能在实践应用中体现了较高的应用价值,但是目前压力型锚杆(索)的理论研究远滞后于工程应用。论文以重庆市科技计划攻关项目“锚固体系在地质灾害治理中的应用研究”(项目编号:CSTC2008AC0077)以及国家科技支撑计划项目“地下开挖工程岩土加固关键技术研究”的子课题之一“基坑支护优化计算方法研究”(项目编号2008BAJ06B04-2)为依托,在总结前人研究成果以及现场调研的基础上对压力型锚固体系受力机理进行了分析,结合实际工程进行现场试验,对压力型锚索桩支护体系的锚索预应力,桩、板土压力,桩身内力以及桩锚协调问题进行分析,在理论与试验研究的基础上对压力型锚固体系的工程应用问题进行总结与探讨。论文主要做了以下几个方面的工作:①根据理论分析和现场试验对压力型锚索的受力机理进行了分析。理论分析了压力型锚索锚固段应力分布,通过应用一种小体积测试元件—应变砖对压力型锚索锚固段应变进行测试,对测试结果进行了分析,根据测试结果推演计算获取了压力型锚索锚固段应力分布曲线,并将试验结果与弹性理论解进行了比较分析。对传统拉力型锚索以及压力型锚索的受力机理以及承载性能等进行了对比研究,可得压力型锚索的承载性能优于拉力型锚索。②选取了应用较多的桩锚支护体系进行现场试验,将压力型锚索应用于桩锚支护体系进行工程应用研究,重庆大学农学及生命科学研究院大楼环境挡墙的A-B-C-D-E段设计采用预应力锚索桩-板挡墙的支护体系进行支护。现场试验对支护体系桩、板土压力,锚索以及桩身截面钢筋应力采用了相应的测力计进行测试。通过现场张拉试验获得了桩-锚-板支护体系中预应力锚索的P~s曲线,对比拉、压力型锚索的P~s曲线分析两种锚索不同变形性能。③对基坑的开挖及预应力锚索张拉、桩背填土以及竣工后的支护体系的工作情况进行了全程监测,从而获取了大量的现场测试资料。通过长期的现场监测工作,对锚索预应力大小与预应力损失、作用于桩、板上的土压力以及桩身内力进行了分析,获得了具有代表意义的桩身内力的弯矩图,并与理论计算值进行对比,分析了压力型锚索在支护体系的应用中桩锚协调问题以及锚索的工作性能。论文最后,通过理论以及现场试验的分析与研究,对压力型锚索与抗滑桩共同作用的压力型锚索设计以及压力型锚固体系实际工程应用问题进行了探讨,从而对压力型锚固体系的实践应用提供借鉴。更多还原

【Abstract】 At present, the pile - anchor support system,for its safety, reliability and economical advantages, has been widely used in the process of engineering construction,such as the high and steep slope, deep excavation works and so on. And it makes a large development in the field of geotechnical engineering. Pressure-type anchorage system, as a new anchor, because of its excellent performance in practical application, reflects the higher value. But now the pressure-type anchorage system is far lagging behind the theory of engineering applications. The paper originated from the scientific and technological project of Chongqing technological committee“Anchorage System in the Geological Disaster Control Research”(Grant No. CSTC2008AC0077) and National Science and Technology Support Program project on " Study on Underground excavation Geotechnical reinforcement of key technologies " Sub-topics“Study on Excavation Optimization Method”(Grant No. 2008BAJ06B04-2). In summing up the results of previous studies and field research, analyzed the mechanism of pressure-type anchorage system stress on the basis of theoretical and experimental aspects. Meanwhile, through filed tests, this thesis has analized the application of pressure to anchor (cable) pile - anchor supporting system’s anchor cable pull, pile, soil pressure plate and the shaft Moment and pile anchor coordination. On the basis of theoretical and experimental research, the pressure-type anchor (cable) pile system engineering applications are discussed. Some detailed work has been done as follows:①Studies were made on the fore mechanism of pressure-type anchor according to the theoretical analysis and field test. For one hand, the stress of the pressure-type anchorage segments, which were calculated based on the test of the strain of anchorage segments in a small volume of test components– strain brick, was compared with the elasticity solution of it. For another, study on the mechanism and the force bearing capacity comparative of traditional tension-type cable and pressure-type cable, to obtain the bearing of pressure-type cable is better than tension-type anchor conclusions.②The paper chose commonly used pile - anchor support system to do the filed test, and make an engineering application study on pile - anchor support system which used pressure-type anchor. The environmental retaining wall ABCDE segment of the Agriculture and Life Sciences college building has been designed with prestressed piles - plate retaining wall, in order to back up the support system. The test measured the stress of the support system’s piles, the soil pressure of the plate, the cabal and the steel in the piles with force senser. And through tension test to get the P~s curves of pre-stress anchor cables used in the pile - anchor support system. Through the contrast and analysis of the P~s curves from tension-type anchor and pressure-type anchor, we can get their different deformation behaviors.③The pit excavation , tension of the prestressed anchor cable, and the process of plain fill and the work condition of the completion support system are monitored during the entire process, so that we can attain a great deal of on-site tests data. Through comprehensive on-site monitoring work and analysis on the prestress value and loss of anchorage cable, the soil pressure of the pile and plate, we can get representative moment graphs of the pile.Then the author compared with theoretical values, analysis coordination and anchor pile anchor performance situation of pressure-type cable support system in the application .Finally, on the basis of theory and analysis of field tests, the pressure-type anchor (cable) and the interaction of piles supporting system design method and pressure-type anchorage system practical application issues are discussed, and some references for the pressure-type anchor Rod’s applications will be provided by this paper.更多还原