非对称荷载下内撑式基坑支护结构参数分析及设计优化探讨  

Parameter analysis and discussion on design optimization of support structure of internal bracing foundation excavation under asymmetric loads

作　　者：孙志浩 徐长节[1,2,3,4] 房玲明 黄福明[5] 黄展军 范润东 SUN Zhihao;XU Changjie;FANG Lingming;HUANG Fuming;HUANG Zhanjun;FAN Rundong(College of Civil Engineering and Architecture,Zhejiang University,310058 Hangzhou,China;Center for Balance Architecture,Zhejiang University,310058 Hangzhou,China;Jiangxi Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering,East China Jiaotong University,330013 Nanchang,China;Engineering Research&Development Centre for Underground Technology of Jiangxi Province,East China Jiaotong University,330013 Nanchang,China;First Investigation&Design Company,Zhejiang University,310058 Hangzhou,China;Nanchang Rail Transit Group Co.,Ltd.,330013 Nanchang,China;Zhejiang Hanghai Intercity Railway Co.,Ltd.,314000 Jiaxing,China)

机构地区：[1]浙江大学建筑工程学院,杭州310058 [2]浙江大学平衡建筑研究中心,杭州310058 [3]华东交通大学江西省岩土工程基础设施安全与控制重点实验室,南昌330013 [4]华东交通大学江西省地下空间技术开发工程研究中心,南昌330013 [5]浙江大学福世德勘测设计研究院,杭州310058 [6]南昌轨道交通集团有限公司,南昌330013 [7]浙江杭海城际铁路有限公司,嘉兴314000

出　　处：《应用力学学报》2024年第1期158-168,共11页Chinese Journal of Applied Mechanics

基　　金：国家杰出青年科学基金资助项目(No.51725802);国家自然科学基金资助项目(No.51878276);浙江省自然科学基金委员会-华东院联合基金资助项目(No.LHZ19E080001);国家自然科学基金-高铁联合基金资助项目(No.U1934208);江西省自然科学基金资助项目(No.20192ACB20001)。

摘　　要：非对称荷载作用下,内撑式基坑会向荷载小侧整体偏移,这将不利于基坑的稳定,因此有必要对支护结构进行设计优化。本研究以某偏压综合管廊基坑为例,通过有限元软件PLAXIS 2D对该基坑进行了仿真模拟,模拟结果与实测数据吻合良好,验证了模型的有效性。进一步对该基坑进行参数分析,研究了支护结构长度、等效厚度和弹性模量对支护结构变形和基坑安全性的影响。研究结果表明,在两侧支护结构均按偏压侧进行设计的基础上,增大某侧支护结构长度,会使该侧支护结构水平位移最大值增大,分别增大两侧支护结构等效厚度、弹性模量,均可以减小该侧支护结构水平位移最大值和非偏压侧支护结构顶部逆向位移。基于参数分析,提出一种针对非对称荷载基坑的简单有效、经济可行的优化思路,并通过数值模拟对优化效果进行了分析,证明了该优化思路的可行性。Under the action of asymmetrical load,the internal bracing foundation excavation will skew to the small side of the load,which will be deleterious to the stability of the foundation pit,so it is necessary to optimize its design.A unsymmetrical loaded pipe gallery foundation pit is used as an example in this paper,and the finite element software plaxis 2D was used to simulate this foundation pit.The simulation results are in good agreement with the measured data,which verifies the validity of the model.Then the supporting structure parameters of the foundation pit are analyzed,and the influence of the length,equivalent thickness and elastic modulus of the supporting structure on the deformation of the supporting structure and the safety of the foundation pit is studied.The research results show that when the supporting structures on both sides are designed according to the biased side,the maximum horizontal displacement of a side supporting structure increases with the equivalent thickness of the side supporting structure.And with the increase of the equivalent thickness and elastic modulus of the supporting structure on both sides,the maximum horizontal displacement of the side supporting structure and the reverse displacement of the top of the non-biased side supporting structure will decrease.Finally,a simple and economical optimization idea for asymmetric load foundation pits is proposed by parameter analysis,and the optimization effect is analyzed through numerical simulation,which proves the effectiveness of the optimization idea.The conclusions and optimization idea can provide references for similar projects.

关 键 词：基坑工程 非对称荷载 有限元 参数分析 优化措施 

分 类 号：TB115[理学—数学]