新型倒T式防波堤结构长期变形特性预测方法

摘要

新型倒T式防波堤结构是可供深水环境软土地基选用的一种新型港工结构型式.深水环境中结构所受波浪力、水流力等长期循环荷载作用显著,但其长期变形特性尚不清楚.为探讨该类结构长期变形特性,基于波浪等循环荷载长期作用下软黏土变形与循环次数之间相互关系同静荷载作用下土体蠕变与时间之间相互关系类似的特性,借鉴蠕变理论,采用幂指数函数拟合饱和软黏土循环三轴试验结果,结果显示二者吻合较好,说明基于蠕变理论采用幂指数函数预测饱和软黏土长期变形的方法是可行的.进一步,利用ABAQUS二次开发平台Creep子程序实现了这一方法的有限元计算手段,建立了预测饱和软黏土长期变形的有限元实用简化计算方法.最后,采用该方法探讨了新型倒T式防波堤结构的长期变形特性.%Inverse T-type breakwater structure is a new type of port engineering structure suitable for soft soil foundation in deep water .The wave force and current force on the structure are remarkable in deep water , but its long-term deformation characteristics are still unclear .In order to study them , according to the characteristic that the cyclic cumulative deformation of soft clays is similar to the creep under the static load , by virtue of the creep theory, using the power exponential function fitting the cyclic triaxial test results of saturated soft clay .The results are in good agreement , and it shows that the method of using the power exponential function predicting the long -term deformation of saturated soft clay basing on creep theory is feasible .Further , employing the Creep subroutine of ABAQUS on the secondary development of platform implementing the finite element calculation method , the practical and simplified finite element calculation method is established .Finally, the long-term deformation charac-teristics of the New inverse T-type breakwater structure are discussed by this method .