基于振动台试验的加筋土柔性桥台抗震设计参数取值方法对比分析  

Comparative analysis of seismic design parameter values for geosynthetic-reinforced soil abutment based on shaking table test

作　　者：罗敏敏 徐超[2] 梁程[3] 沈盼盼 陈赟 LUO Minmin;XU Chao;LIANG Cheng;SHEN Panpan;CHEN Yun(The Architectural Design and Research Institute of Zhejiang University Co,Ltd.,Hangzhou 310028,China;Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China;Institute of Science and Technology,China Three Gorges Corporation,Beijing 100038,China;Shanghai Investigation,Design&Research Institute Co,Ltd.,Shanghai 200434,China)

机构地区：[1]浙江大学建筑设计研究院有限公司,浙江杭州310028 [2]同济大学地下建筑与工程系,上海200092 [3]中国长江三峡集团有限公司科学技术研究院,北京100038 [4]上海勘测设计研究院有限公司,上海200434

出　　处：《中南大学学报（自然科学版）》2024年第1期375-387,共13页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41772284)。

摘　　要：目前土工合成材料加筋土柔性桥台(GRS桥台)在静力荷载作用下的设计、施工已有标准化的技术指南,但对于GRS桥台的抗震设计方法,只有一些原则性和框架性的建议,没有具体参数的取值方法,需要进一步完善。首先对国内、外相关规范或标准中关于加筋土挡墙抗震设计参数取值的方法进行列表汇总与比较,定性地分析其异同。在此基础上,结合1g重力场下的振动台缩尺模型试验监测数据,通过试验实测值与规范取值的对比,检验现有加筋土挡墙抗震设计参数取值方法对GRS桥台的适用性,并提出相关建议。研究结果表明:GRS桥台产生较大变形的临界加速度至少为0.6g,大于一般加筋土挡墙的0.3g~0.4g;在达到临界加速度(0.6g)之前,GRS桥台基本不受损伤且侧向变形增量不超过0.5%,因此建议GRS桥台的抗震设计按桥台侧向变形增量不超过0.5%进行控制。在此前提条件下,国外NCMA、FHWA和AASHTO规范对于水平地震系数的取值方法基本适用于GRS桥台,可用于GRS桥台整体外部稳定性的验算;对于GRS桥台面层顶部局部稳定性的验算,则需借鉴国内公路规范的理念,进一步研究提出更为合理的加速度放大系数取值方法。NCMA规范关于筋材轴力动力增量的取值方法适用于GRS桥台,且在设计上偏于安全;FHWA和AASHTO规范的方法则需修正后才能使用。At present,there are standardized technical guidelines for the design and construction of geosynthetic reinforced soil abutments(GRS abutments)under static loads,but for the seismic design methods of GRS abutments,there are only some principles and frameworks.There is no specific parameter value method,which needs to be further improved.Firstly,the methods for calculating the parameters of seismic design of geosynthetic reinforced earth retaining walls in relevant domestic and foreign codes or standards were listed and compared,and the similarities and differences were analyzed qualitatively.Then,combined with the monitoring data of the shaking table scale model test under the 1g gravity field,the applicability of the existing seismic design parameter selection method of reinforced earth retaining wall to GRS abutment was tested and relevant suggestions were put forward through the comparison between the actual measured value and the standard value.The results show that the critical acceleration value for the large deformation of the GRS abutment is at least 0.6g,which is greater than 0.3g-0.4g of the general reinforced soil retaining wall,and that before reaching the critical acceleration(0.6g),the GRS abutment is basically not damaged,and the lateral deformation increment does not exceed 0.5%.Therefore,it is recommended that the seismic design of the GRS abutment should be controlled so that the lateral deformation increment of the abutment does not exceed 0.5%.Under this premise,the value method of the horizontal seismic coefficient in the foreign NCMA,FHWA and AASHTO codes is basically applicable to the GRS abutment,and can be used for the calculation of the overall external stability of the GRS abutment;as for the local stability at the top of the GRS abutment,it is necessary to learn from the concept of domestic highway regulations,and further study and propose a more reasonable method for the value of acceleration amplification factor.The value method of the NCMA code for the dynamic increment of the axial

关 键 词：桥涵工程 抗震设计 土工合成材料 加筋土桥台 振动台试验 

分 类 号：U443.2[建筑科学—桥梁与隧道工程]