基坑地表沉降的偏态分布函数应用  

Application of Skewed Distribution Function to Predicting Surface Settlement Induced by Excavations

作　　者：易顺 潘家军[1] 王艳丽[1] 徐晗[1] 白强强 杨志勇 YI Shun;PAN Jia-jun;WANG Yan-li;XU Han;BAI Qiang-qiang;YANG Zhi-yong(Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources,Changjiang River Scientific Research Institute,Wuhan 430010,China;China Construction Sixth Engineering Bureau Co.,Ltd.,Tianjin 300171,China;Academy of Railway Sciences Engineering Consult Co.,Ltd.,Beijing 100081,China)

机构地区：[1]长江科学院水利部岩土力学与工程重点实验室,武汉430010 [2]中国建筑第六工程局有限公司,天津300171 [3]铁科院(北京)工程咨询有限公司,北京100081

出　　处：《长江科学院院报》2024年第8期135-141,179,共8页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金项目(U21A20158,52008032);中央级科研院所基本科研业务费项目(CKSF2021484/YT,CKSF2021459/YT);铁科院(北京)工程咨询有限公司科研项目(2021ZXJ009)。

摘　　要：城市深基坑工程施工不可避免会引起周围地层变形尤其是坑外地表沉降,而过大的地表沉降会对周围建(构)筑物造成严重威胁,因此有必要开展基坑地表沉降方面的研究。针对目前在基坑地表沉降变形表征函数和表征指标方面研究的不足,利用偏态分布函数描述坑外地表沉降规律,并对沉降曲线的变形表征指标进行研究,形成一套适用于地表偏态沉降形式的变形表征指标体系,继而提出坑外地表沉降的偏态分布函数预测方法。在此基础上,依托2个工程实例,验证偏态分布函数及其指标体系和预测公式的适用性,主要得到了以下结论:利用偏态分布函数来描述坑外地表沉降曲线更为合理;结合沉降曲线包络面积、最大地表沉降及其位置等指标,提出以显性表征指标和隐性表征指标为核心的坑外地表沉降曲线表征指标体系;利用偏态分布函数展开回归分析和预测研究,发现地表沉降曲线与实测数据总体上较为接近,说明偏态分布函数在基坑地表沉降研究中的合理性和适用性。The construction of deep excavations inevitably disturbs surrounding strata,particularly causing excessive surface settlement which can significantly threaten nearby buildings.It is essential to study surface settlement in excavations.To enhance current research on characterizing functions and indicators for surface settlement,we employ the skewed distribution function to describe surface settlement,and propose a set of indicator system applicable to excavations by scrutinizing the characterizing indicators of the settlement curves.On this basis,we put forward a skewed distribution function for predicting surface settlement.The applicability and effectiveness of the skewed distribution function as well as the indicator system and the prediction function in describing excavation-induced surface settlement are validated through analyzing two practical engineering projects.Findings demonstrate the rationality of the skewed distribution function in describing excavation-induced surface settlement.The characterizing indicator system,with explicit and implicit indicators at its core,takes into consideration the settlement curve envelope area,the maximum surface settlement and its location.Regression and prediction using the skewed distribution function demonstrate a close alignment between predicted settlement curves and actual data,confirming the function’s rationality and applicability for describing surface settlement in excavations.

关 键 词：基坑工程 地表沉降 偏态分布形式 表征函数 表征指标 

分 类 号：TU442[建筑科学—岩土工程]