摘要
文中以某地区超深基坑工程为研究对象,设置微型钢管桩支护结构,通过原位开挖试验得到支护结构在开挖过程中的结构受力情况。研究发现,在基坑开挖过程中,支护结构的内排桩和外排桩所受到的弯矩分布相似,与基坑开挖的深度没有直接关系,但在开挖深度较浅时,内排桩相较于外排桩对于基坑的稳定性起到了主要的影响,随着开挖深度的逐渐增加,两者对基坑稳定性造成的影响逐渐相同。稳定性较差的土层在开挖时会导致支护结构受到较大的弯矩;岩体在开挖时会造成较大的震动,导致支护结构桩身受力增大。预应力锚索能够降低支护结构所受到的弯矩,在工程应用中合理布置预应力锚索,能有效降低施工风险。
This paper focuses on a super-deep excavation project in a certain region,with the installation of a mini steel pipe pile support structure.Through in-situ tests,the structural stress of the support system during the excavation process is obtained.It is found that the bending moment distribution in the internal and external braced piles of the support structure is similar during excavation,and it is not directly related to the depth of excavation.However,at shallow excavation depths,the internal braced piles have a major impact on the stability of the excavation compared to the external braced piles.As the excavation depth gradually increases,the impact of both on the excavation stability becomes similar.Excavation in unstable soil layers can result in significant bending moments on the support structure,while rock excavation can cause substantial vibrations,leading to increased stress on the pile body of the support structure.Pre-stressed anchor cables can reduce the bending moments on the support structure,and the rational arrangement of pre-stressed anchor cables in engineering applications can effectively decrease construction risks.
作者
戴名扬
丁俊男
Dai Mingyang;Ding Junnan(Nuclear Industry Jiangxi Engineering Survey and Research Institute Co.Ltd.,Nanchang,Jiangxi 330046)
出处
《江西建材》
2023年第6期80-82,85,共4页
Jiangxi Building Materials
关键词
基坑
支护结构
原位试验
预应力锚索
Excavation pit
Support structure
Iin-situ test
Pre-stressed anchor cables