摘要
以某坑边荷载距离不同的综合管廊基坑为例建立二维有限元模型,土体采用小应变本构模型,计算结果与实测数据吻合良好,验证了模型的有效性.在此模型基础上,通过改变基坑一侧荷载的距离建立多组模型,研究两侧荷载距离不同对支护结构变形受力、支撑位移以及坑底隆起的影响.结果表明,当非紧邻侧荷载离坑边距离超过0.2倍开挖深度时,荷载距离较远侧支护桩发生桩顶逆向位移,两侧支护桩弯矩最大值差异率>10%,两侧支护桩配筋应按两侧荷载情况分别考虑;当非紧邻侧荷载距离坑边超过1.0倍开挖深度时,内支撑会随支护结构变形发生向荷载距离较远侧的整体偏移;两侧荷载距离非对称情况下,坑底隆起曲线呈非对称分布.
A two-dimensional finite element model was established by taking a pipe gallery foundation pit with different load distances near the pit as an example.The soil was modeled by hardening the small soil constitutive model.The calculated results of the model were in good agreement with the measured data,which verified the validity of the model.Based on this model,multiple sets of models were established by changing the load distance on one side of the foundation pit,and the influence of load distances on both sides on the stress and deformation of the supporting structure,the displacement of the supporting and the bottom heave were studied.The results showed that,when the distance between the non-adjacent side load and the pit side was more than 0.2 times of the excavation depth,the pile top reverse displacement occurred in the supporting pile at the far side of the load distance,and the difference rate of the maximum bending moment of the supporting piles on both sides was greater than 10%.The reinforcement of the supporting piles on both sides should be considered according to the load conditions on both sides.When the load on the non-adjacent side exceeded 1.0 times the excavation depth of the pit side,the internal support would shift to the far side with the deformation of the supporting structure.When the load distance on both sides was asymmetric,the uplift curve of pit bottom was asymmetric too.
作者
孙志浩
张兴周
葛佳佳
徐长节
孔跃跃
范晓真
SUN Zhi-hao;ZHANG Xing-zhou;GE Jia-jia;XU Chang-jie;KONG Yue-yue;FAN Xiao-zhen(Center for Balance Architecture,College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China;Hangzhou Hydro Construction Group Co.,Ltd,Hangzhou 310000,China;Zhejiang Hanghai Intercity Railway Co.,Ltd,Jiaxing 314000,Zhejiang,China;Key Laboratory of Infrastructure Safety Control in Geotechnical Engineering of Jiangxi Province,Engineering Research&Development Centre for Underground Technology of Jiangxi Province,East China Jiaotong University,Nanchang 330013,China;China Railway 14th Bureau Group 4th Engineering Co.,Ltd.,Ji'nan 250002,China)
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第6期735-743,共9页
Journal of Lanzhou University(Natural Sciences)
基金
国家杰出青年科学基金项目(51725802)
国家自然科学基金项目(51878276)
浙江省自然科学基金委员会-中国电建集团华东勘测设计研究院联合基金项目(LHZ19E080001)
国家自然科学基金委员会-中国国家铁路集团有限公司高速铁路基础研究联合基金项目(U1934208)
江西省自然科学基金重点项目(20192ACB20001)。
关键词
基坑工程
小应变本构
不平衡基坑
有限元分析
荷载距离
非对称荷载
excavation engineering
small strain constitutive
unbalanced foundation pit
finite element method analysis
load distance
asymmetric load
