摘要
沉管隧道基槽回填是沉管隧道施工中的重要工序,而其对沉管隧道的抗震减震性能影响规律在现有研究中鲜有提及。为探究沉管隧道柔性接头在不同回填材料刚度下的位移量,基于多质点-弹簧-梁模型,结合纵向反应位移法,运用考虑纵向限位装置的柔性接头轴向受力分析模型,以广州市如意坊沉管隧道为背景,开展P波入射下的纵向动力响应分析数值试验。计算结果表明:数值模型与计算方法能够得到合理的场地与结构响应;采用纵向反应位移法进行计算分析时应提取自由场中隧道截面对应位置处的多点位移时程作为结构的激励;未经处理的淤泥质软黏土不能作为基槽回填材料,将砂土或砾石作为基槽回填材料时,若增大其密实度,其抗震能力可获得进一步提高。该研究结果可为沉管隧道在地震作用下的响应分析与抗震设计提供更为可靠完善的计算模型与设计依据。
The backfilling of foundation groove of immersed tunnels is an important procedure in the construction,but the influence mechanism of its seismic performance is seldomly mentioned in the previous researches.In order to investigate the influences of the stiffness of backfill materials on the deformation of flexible joints in the immersed tunnels,the numerical tests of longitudinal dynamic response analysis under incidence of P waves are carried out for Ruyifang immersed tunnel in Guangzhou by using the particle-spring-beam model with implementation of the longitudinal displacement method and the flexible joint model with the longitudinal limit devices.The results show that the numerical model and method can make the structures respond in a timely and reasonable manner.When the longitudinal response displacement method is used for calculation and analysis,the time histories of multi-point displacement in the free field should be extracted as the excitation of the structures.The untreated soft silt clay cannot be used as the backfill materials.If the density of sand or gravel is increased,the seismic capacity will be further improved.The research results may provide a more reliable model and design basis for the response analysis and seismic design of immersed tunnels under earthquakes.
作者
李亚东
周金雯
单毅
崔杰
魏立新
LI Yadong;ZHOU Jinwen;SHAN Yi;CUI Jie;WEI Lixin(College of Civil Engineering,Guangzhou University,Guangzhou 510006,China;Key Laboratory of Earthquake Resistance,Earthquake Mitigation and Structural Safety,Ministry of Education,Guangzhou 510006,China;Guangzhou Municipal Engineering Design and Research Institute Co.,Ltd.,Guangzhou 510060,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2023年第6期1190-1199,共10页
Chinese Journal of Geotechnical Engineering
基金
国家重点研发计划(2022YFC3003601)
国家自然科学基金(52020105002,51991393)
广州市校(院)联合资助项目基础与应用基础研究(202201020155)。
关键词
沉管隧道
动力分析
简化模型
柔性接头
回填材料
immersed tunnel
dynamic analysis
simplified model
flexible joint
backfill material
