输电线路掏挖基础承载特性离心机试验研究  

Centrifuge model test study on bearing capacity of excavated foundations of transmission lines

作　　者：郝冬雪[1] 柳竺江 陈榕[1] 薛琰 赵维[3] HAO Dongxue;LIU Zhujiang;CHEN Rong;XUE Yan;ZHAO Wei(School of Civil Engineering and Architecture j Northeast Electric Power University j Jilin,Jilin 132012,China;Dongguan Power Supply Bureau of Guangdong Power Grid Corporation,Dongguan,Guangdong 523000,China 523000;Institute of Geotechnical Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China)

机构地区：[1]东北电力大学,建筑工程学院,吉林吉林132012 [2]广东电网有限责任公司东莞供电局,广东东莞523000 [3]大连理工大学岩土工程研究所,辽宁大连116024

出　　处：《岩石力学与工程学报》2020年第9期1921-1929,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51308095);吉林省科技厅青年科研基金(20130522068JH)。

摘　　要：掏挖基础是输电线路建设中广泛采用的基础型式,但对其复合加载承载特性的研究较少。针对不同荷载工况下坚硬黏性土地基中掏挖基础承载特性,开展离心机模型试验研究。结果表明,单独上拔荷载作用下,地基破坏模式受基础埋深比的影响,浅及深埋的临界埋深比在2~3范围;水平荷载作用下,对于高露头基础,随着露头高度增加水平承载力明显降低;对埋深比为2的无露高基础,先施加水平力会使其极限上拔承载力有所提高,施加的水平力越大,基础抗拔能力越强;对埋深比为2的有露高基础,在施加相同水平荷载和相同弯矩2种情况下,基础的净峰值抗拔力与无露高基础HV组合加载时的抗拔承载力相差均小于10%,即高露头产生的弯矩对HV组合加载时基础上拔承载力的影响相对不大。所得结论可为不同荷载工况下输电线路掏挖基础设计提供一定参考。The excavated foundations have been widely used in transmission line construction. The bearing capacity characteristics of excavated foundations in stiff clay under different loading conditions are investigated in this study by a series of centrifugal model tests. The results show that the failure mode of foundation soil under solo uplift loading is affected by the embedment ratio of foundations and the critical embedment ratio is between 2 and 3. For high outcropping foundations,the horizontal bearing capacity will reduce significantly with increasing the dimensionless outcropping height. The ultimate uplift capacity of no outcropping foundations with an embedment ratio of 2 will increase to some extent when the horizontal load is applied first. The greater the horizontal load,the stronger the uplift capacity. Under the same horizontal load at the foundation top and the same moment at the ground point before pullout,the ultimate uplift resistance of outcrop foundations with an embedment ratio of 2 has a difference no more than 10% with that of no outcrop foundations,which indicates that the moment of outcrop foundations at the ground point has no obvious influence on the uplift resistance under combined uplift and horizontal loading. The research work can provide a reference for the design of excavated foundations of transmission lines in various loading cases.

关 键 词：基础工程 掏挖基础 硬黏性土 离心机试验 复合加载模式 承载特性 

分 类 号：TU47[建筑科学—结构工程]