(1 建筑安全与环境国家重点实验室, 北京 100013; 2 国家建筑工程技术研究中心, 北京 100013;3 中国建筑科学研究院有限公司地基基础研究所, 北京 100013)

摘要: 某核电站核岛厂房位于深厚的第四系覆盖土层,初步设计采用桩筏基础方案,现场已开展原状土地基和经振冲碎石桩处理后地基的桩基础原位试验工作. 通过对试验数据的分析可知,地基处理后桩间土达到密实状态,完全消除了地基液化隐患,单桩及群桩水平承载力特征值相对处理前分别提高了 60%和 45%,地基处理效果显著.由于振冲碎石桩对软弱桩间土的振密效果有限,现场桩基载荷试验得到的单桩水平承载力特征值未能达到设计要求. 通过对多种地基处理方案的综合分析,推荐采用直径 600mm、间距 1. 0m 的振冲碎石桩方案结合增加基础埋深措施,或者采用对地基土加固效果更好的满堂咬合布置的水泥搅拌桩方案,并给出地基处理范围及深度.

关键词: 核岛厂房; 地基处理; 振冲碎石桩; 水泥搅拌桩; 水平承载力

中图分类号:TU472 文献标志码:A 文章编号:1002⁃848X(2022)08⁃0135⁃05

DOI:10. 19701 / j.jzjg.LS201816

Analysis of the ground treatment scheme for the nuclear island plant of a nuclear power station

SUN Wei1,2,3, ZHAO Xiaoguang1,2,3, GAO Wensheng1,2,3, QIU Rendong1,2,3

(1 State Key Laboratory of Building Safety and Built Environment, Beijing 100013, China; 2 National EngineeringResearch Center of Building Technology, Beijing 100013, China; 3 Institute of Foundation Engineering of ChinaAcademy of Building Research, Beijing 100013, China)

Abstract: The nuclear island plant of a nuclear power station is based on a thick quaternary overburden soil layer. Pile⁃raftfoundation was adopted in the preliminary design. In⁃situ test of pile foundation was carried out both on the undisturbedground and the ground treated by vibro⁃replacement stone columns. Study on the test data shows that the soil between pileshas reached a dense state and the liquefaction of the ground has been eliminated completely after ground treatment.Horizontal bearing capacity characteristic value of single pile and pile group has increased by 60% and 45% respectivelycompared with that before ground treatment, which shows that the ground treatment effect is significant. Due to the limitedcompaction effect of vibro⁃replacement stone columns on soft soil between piles, the characteristic value of the horizontalbearing capacity of single pile obtained from the field static load test fails to meet the design requirement. Two groundtreatment schemes are recommended through the comprehensive analysis of a variety of ground treatment schemes. The firstone is the vibro⁃replacement stone column scheme with a diameter of 600mm and a spacing of 1. 0m in combination withmeasure of increasing the buried depth of foundation. The second one is the cement mixing pile scheme with 100%replacement rate, which has good effect on ground improvement. The range and depth of the ground treatment were given.

Keywords:nuclear island plant; ground treatment; vibro⁃replacement stone column; cement mixing pile; horizontalbearing capacity

第一作者:孙威,博士,工程师,主要从事地基处理及基坑工程的设计咨询与研究工作,Email: sunweicabr@ 163.com.

[引用本文] 孙威,赵晓光,高文生,等. 某核电站核岛厂房地基处理方案分析[ J]. 建筑结构,2022,52(8):135⁃139,79. SUN Wei, ZHAO Xiaoguang, GAO Wensheng, et al. Analysis of the ground treatment scheme for the nuclearisland plant of a nuclear power station[J]. Building Structure,2022,52(8):35⁃139,79.