【作者】 胡井友；

【导师】 李成辉； 曾宪明；

【作者基本信息】 西南交通大学 ， 土木工程， 2003， 硕士

【摘要】 论文主要对复合土钉支护稳定性及应用情况进行相关研究。基于复合土钉支护技术国内外应用和研究情况，介绍了复合土钉支护技术的国内外应用和研究现状、发展动态。结合复合土钉支护技术的实际工程应用，分析了复合土钉支护的主要构型以及复合土钉支护的作用机理。对复合土钉支护的稳定性进行了分析。在稳定性分析中，研究了复合土钉支护时土坡稳定的安全系数：介绍了最危险滑裂面的确定方法并采用几何参数控制法来确定土体的最危险滑裂面；计算了土钉支护土体时的稳定性；研究了水、预应力锚杆(索)、水泥土搅拌桩以及超前微桩对复合土钉支护时土体稳定性的影响作用并给出了相应的计算公式。为了进一步研究复合土钉支护技术，论文进行了深基坑复合土钉支护模型的试验研究，比较了复合土钉支护深基坑与普通土钉支护深基坑时的支护效果。最后，基于工程实践，论文介绍了几个复合土钉支护的工程应用实例，在各工程应用中分别采用了不同的复合土钉支护构型。 理论研究结果表明，针对不同的地质条件可采用普通土钉支护技术或复合土钉支护技术，在采用复合土钉支护技术时又可采用不同的复合构型；复合土钉支护的作用机理主要是以土钉支护为主，依据不同土质条件、工程环境，借助于水泥土搅拌桩止水帷幕、超前微桩和预应力锚杆等其它组件的共同作用来稳定土体和边坡。复合土钉稳定性分析表明，复合土钉支护时土坡稳定的安全系数和最危险滑裂面的确定对于稳定性分析非常重要；土体内水对土体稳定性有很大的影响作用；设置超前微桩后，能增加基坑边壁的稳定性；增设深层搅拌桩后，边壁抗倾覆、抗滑移安全系数增大，同时面层强度的增加更有利于复合土钉支护体系内其它组件间的相互作用；增设预应力锚杆(锚索)和预应力土钉，对于控制基坑边壁位移有重要作用，可明显提高滑移面上土体的抗滑力。 深基坑复合土钉支护模型的试验研究结果表明，复合土钉支护的变形与普通土钉支护相比，具有不同的分布形态；由于土钉与水泥土搅拌桩的共同作用，可有效地控制基坑变形，提高基坑的稳定性。 实际工程应用情况表明，复合土钉支护技术对于复杂地质条件下土木工程基坑、边坡等的支护是有效可行的，可依据不同的地质条件采用不同的复合土钉支护构型。更多还原

【Abstract】 In this paper, the applications and the stability analysis of compound soil nailing were studied. Based on the fact of the applications and the researches on compound soil nailing in land and overseas, it were introduced that the applications and the researches on compound soil nailing in land and overseas nowadays. With the engineering applications of compound soil nailing, main types of compound soil nailing and their working mechanism were analyzed. The stability of compound soil nailing was also analyzed. During the stability analysis, the safety coefficient and the most dangerous slipped layer of soil slope retained by compound soil nailing was studied. The stability of soil nailing was calculated. Then, the influence functions of water, prestressed anchor and cement-soil retaining wall and front small-piles in the compound soil nailing system were studied. The corresponding formulas were given. A model test of the compound soil nailing for deep excavation was carried out in laboratory in order to study the working mechanism of compound soil nailing deeply. The retain effects of compound soil nailing and those of soil nailing were compared in this experiment. At the last, some civil engineering structures retained by the compound soil nailing were introduced.The results of theory researches show that the selection in the types of compound soil nailing should base on the geologic condition of soil slope. The working mechanism of compound soil nailing depend on the soil nailing mainly, the other part such as prestressed anchor and cement-soil retaining wall and front small-piles in the compound soil nailing system can also take part in. The researches on the stability of compound soil nailing show that it is important to determine the safety coefficient and the most dangerous slipped layer of soil slope retained by compound soil nailing in the stability analysis of compound soil nailing. Water, prestressed anchor and cement-soil retaining wall and front small-piles in the compound soil nailing system have a great influence on the stability of the whole compound soil nailing system. The front small-piles in the compound soil nailing system can improve the stability of the soil slope. The cement-soil retaining wall in the compound soil nailing system can increase the safety coefficient of soil slope retained by compound soil nailing. The prestressed anchor in the compound soil nailing system can increase the slipped resistant force JAevidently, and it make very important in controlling the distance nearby the excavation.The experimental results show that the deformation profiles of compound soil nailing were different from those of soil nailing, and the cooperation of the nail and the soil-cement piles can control the deformation induced by excavation effectively and improve the stability of the excavated slope.The applications of compound soil nailing on the civil engineering structures show that the compound soil nailing technology can retain the excavation and the soil slope in the complicated geologic condition. And it also shows that Selection in the types of compound soil nailing should base on the geologic condition of soil slope.更多还原