【摘要】 为了准确获得盾构管片的开裂行为,选择合适的混凝土裂缝模型和参数是关键。基于已有管片试验成果建立了有限元模型,针对管片跨中挠度曲线、钢筋应变曲线和管片开裂模式等结构响应验证了数值模型的可靠性。参数分析研究了旋转裂缝模型、固定裂缝模型和多向固定裂缝模型3种弥散裂缝模型带来的影响,计算结果表明:旋转裂缝模型结果能够还原管片屈服后跨中的位移响应,同时裂缝形态与试验结果具有一致性。另外,针对拉伸和压缩断裂能进行参数敏感性分析,结果表明,2种断裂能都对管片承载力影响较大,源于规范Fib Model Code 2010的断裂能取值办法在管片开裂分析中的有效性得到验证。更多还原

【Abstract】 An appropriate concrete crack model and parameters should be selected when a precise crack behavior of shield tunnel lining was wanted.Based on the results of lining bearing test,a numerical model was built and its reliability was confirmed.The deflection curve at mid span,strain curve of steel bar and crack pattern were considered in the verification process.Three smeared crack models including rotating crack model,fixed crack model and multi-directional fixed crack model were considered in parameter analysis.The results show that the rotating crack model matched well with the test in deflection response and crack pattern.Besides,fracture energy of tension and compression were considered in sensitive analysis.It turns out that both two fracture energies have great impact on bearing capacity of tunnel segment.And parameter evaluation of fracture energy from standard Fib Model Code 2010 in the analysis of segment cracking has been verified.更多还原