摘要
目前对于土岩二元地层的深基坑多见于青岛、大连等沿海地区,根据该地层特点而采用"吊脚桩+内支撑/锚索"的围护结构体系已有工程实例,但现有设计规范关于吊脚桩的理论计算尚无明确方法,对吊脚桩的传力体系仍模糊不清。针对福建地区花岗岩岩层地质特点,结合"吊脚桩+内支撑/锚索"支护体系在土岩二元地层中的力-变形机理,提出"补偿"设计法和"吊脚桩"基坑的稳定性验算方法,从而得到吊脚桩及锁脚锚索的相关设计参数。随后利用有限元软件模拟花岗岩二元岩土基坑的施工工况,从理论上论证了"补偿"设计法的合理性。最后依托已完成的实际工程,采用现场实时监测的数据,对吊脚桩支护结构的设计计算、吊脚桩的桩身变形进行分析研究,掌握其工作力学特性规律,从实际应用中验证"补偿"设计法的可行性。
At present,the deep foundation pit of the binary strata of the soil and rock is more common in the coastal areas such as Qingdao and Dalian,for this formation characteristics,the application structure of the"dowel pile+inner support/anchor cable"has been applied.However,there is no clear method for the theoretical calculation of the dowel piles,and the force system of the dowels is still obscure.This paper puts forward the"compensation"design method and the"hanging pile"foundation pit stability checking method on the basis of the geologic characteristics of the granite strata in Fujian Province,combined with the force-deformation mechanism of the"dowel pile+inner support/anchor"support system in the soil rock binary strata.Thus further proposes the method to determine the main parameters of the design of anchor pile and the lock anchor.And then,it theoretically demonstrates the rationality of the"compensation"design method by simulating the construction condition of granite binary rock foundation pit on finite element software.At last,relying on the actual projects which has been completed already,it designs and calculates the supporting structure of the dowel pile and analyses the pile body deformation using the live monitoring data.Grounded on the law of the mechanical properties,it illustrate the feasibility of"compensation"design from the practical application completely and comprehesively.
作者
张涵
Zhang Han(China Railway Siyuan Survey and Design Group Co.,Ltd. Wuhan 430063,China)
出处
《广东土木与建筑》
2019年第3期49-53,共5页
Guangdong Architecture Civil Engineering
关键词
二元岩土基坑
吊脚桩
锁脚锚索
岩肩
有限元法
dualistic foundation
end-suspended pile
foot anchors
rock shoulder
finite element method
