摘要
基于改进的节理弹性非线性法向变形本构关系,建立可描述纵波垂直入射层状非线性节理岩体的波传播位移不连续模型,结合一维波动方程特征线法推导层状非线性节理岩体透射波质点速度半数值时域解。利用该解建立差分格式并编写计算程序,通过参数研究初步探求弹性纵波在层状非线性节理处的传播过程及特征,着重分析节理条数N、无量纲节理间距ζ、变形非线性系数ξ、入射波最大振幅vinc与频率f等因素对透射系数|TIMP|、透射波能量比etra、首波波形畸变和时间延迟Tdel产生的影响。研究表明,随着节理条数增加和变形非线性系数增大,|TIMP|、etra减小,Tdel增大;随着节理间距增大,|TIMP|、etra、Tdel均先增大后减小并最终稳定。
Based on the improved elastic nonlinear normal deformational constitutive relationship,a displacement discontinuity model for normally incident P-wave propagation across layered nonlinear joints rockmass was established.Then,combining with the one-dimensional wave equation characteristic method,the semi-numerical time-domain solution of transmitted particle velocity was deduced.Using the solution to establish difference scheme and write calculator program.Parameter studies were conducted to get an insight into the propagation process and the characteristic of elastic P-wave across the layered nonlinear joint rockmass.Mainly analyse the effects of the number of joints N,the nondimensional joint spacing ζ,the extent of nonlinearity ξ,the incident wave maximum amplitude v inc and the frequency f on transmission coefficients T IMP and transmission energy ratio e tra,first arrivals distortion and time delay T del.Calculating results show that T IMP and e tra reduced and T del increased as the augment of N and ξ;T IMP,e tra and T del increased to a certain value at first and then declined and reached a stable value finally.
出处
《土木工程学报》
EI
CSCD
北大核心
2013年第S2期158-165,共8页
China Civil Engineering Journal
基金
国家自然科学基金(51109084)
中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室开放课题(2012002)
关键词
层状岩体
纵波
节理间距
位移不连续模型
非线性系数
半数值时域解
layered rockmass
P-wave
distance of joints
displacement discontinuity model
extent of nonlinearity
semi-numerical time-domain solutions
