带阳角深基坑变形及其影响因素分析  

Analysis on Deformation Characteristics of Deep Foundation Excavation with Positive Corner and Its Influencing Factors

作　　者：王洪德[1,2] 姜天宇[1] 张立漫[1] 

机构地区：[1]大连交通大学土木与安全工程学院,辽宁大连116028 [2]辽宁省隧道与地下结构工程技术研究中心,辽宁大连116028

出　　处：《地下空间与工程学报》2014年第1期156-162,190,共8页Chinese Journal of Underground Space and Engineering

基　　金：辽宁省自然科学基金项目(201202022);国家自然科学基金资助项目(50674052)

摘　　要：深基坑工程大型化、不规则趋势导致其变形影响因素更加复杂。为进一步提高不规则深基坑开挖过程的安全可靠性,借助有限元分析技术,对带阳角土岩组合深基坑变形影响因素进行分析。首先,构建带阳角深基坑有限元分析模型,其中,土体结构采用Mohr-Coulomb模型,岩体结构采用节理材料模型,锚杆、土钉与混凝土结构采用线弹性模型;然后,结合工程实际,通过阳角尺寸、覆土层厚度、锚杆布设等因素的影响分析,对带阳角土岩组合深基坑工程的变形特性进行研究,绘制了土岩组合深基坑变形与覆层土厚度关系曲线,以及不同阳角尺寸和不同覆土层厚度引起的深基坑水平位移变化规律曲线。研究表明,该深基坑阳角与阴角效应显著,阳角最大水平位移随覆土层厚度增加而增大,随护坡结构层厚度增加而减小,随锚杆直径增加而减小。研究可为同类工程的施工安全提供保障,使不规则深基坑工程施工更加科学、合理、经济、可靠。The trends of large-scale, irregular deep foundation pit made its deformation factors more complicat- ed. In order to further improve the safety and reliability for excavation process of irregular deep foundation pit, with the aid of finite element analysis technique, the deformation influencing factors were analyzed for soil rock combina- tion deep foundation pit with positive angle. Firstly, the finite element simulation models of the foundation excavation with positive comer are constructed, among which, the soil structure is modeled with Mohr-Coulomb model, the rock structure modeled with joint material model, the anchors, the soil nailing and the concrete structures modeled with linear elastic models. Secondly, combined with the engineering practice, through the analysis of the influence fac- tors, such as the positive angle size, the overlying soil thickness and the anchor displays, the deformation characteris- tics of the deep foundation pit with positive angle are discussed. The relationship curves of deep foundation pit de- formation with the covering soil thickness are drawn, as well as the horizontal displacement rule curves of the deep foundation pit, which changed with the different positive angle size and the different overlaying soil thickness. Results show that the positive angle and negative angle effect of this deep foundation pit is significant, the maximum horizontal displacements increase with the increase of thickness of the overlying soil, decrease with increase of revetment struc- ture layer thickness, and decrease with the increase of anchors diameter. The study will provide security guarantee for the same sort of engineering excavation and timbering, and make the foundation excavation construction more scientif- ic, more reasonable,more economical and more reliabile.

关 键 词：带阳角深基坑 变形特征 数值仿真 空间效应 对比分析 

分 类 号：X913.4[环境科学与工程—安全科学]