摘要
基于节理非线性位移不连续模型,分析不同弹性纵波正向入射多条节理时的透射规律。利用半解析半数值解法得到透射初至波质点振动速度一维数值差分解,进而研究不同类型、不同振幅的入射纵波穿过多条节理时,初至波质点速度幅值、能量、频谱及时间延迟的变化特性。研究表明,透射能力由大到小的顺序为:矩形波、半正弦波、三角形波。速度透射系数、能量透射系数、透射波中高谐波频域幅值均随入射脉冲幅值增大而增大;延迟时间随入射波振幅的增大而减小,且三角波入射时的时间延迟大于半正弦波。随着节理条数的增加,速度和能量透射系数逐渐降低,且下降速度逐渐减慢;高谐波频域幅值先增大后下降,且下降速度逐渐减慢;时间延迟增大的速度逐渐加快。
Based on the displacement discontinuity model for nonlinear deformation behaviour of fractures,the transmission rule of different normally incident elastic P-wave across multi-fracture is investigated.One-dimensional finite difference solutions of vibration velocity of transmitted wave are obtained by semi-numerical method to investigate the amplitude,energy,spectrum,and time delay of different wave＇s first-arrival pulses.Calculating results show that,in terms of transmission capacity of pulses,the wave ranked from large to small is rectangular wave,half-sine wave and triangular wave.Velocity transmission coefficient,energy transmission coefficient and frequency-domain amplitude of higher harmonic wave increases with the increasing of incident wave amplitude.Time delay decreases with the increasing incident wave amplitude,and triangular pulse＇s time delay is larger than half-sine pulse＇s time delay.Velocity and energy transmission coefficient gradually decrease with a slower speed.Frequency-domain amplitude of higher harmonic increases in the early stage and then decreases gradually with a slower speed.The increase of time delay accelerates with incident wave transmitting across more fractures.
出处
《工程力学》
EI
CSCD
北大核心
2012年第4期1-6,共6页
Engineering Mechanics
基金
国家自然科学基金项目(40702046
51109084)
国防科工委高放废物地质处置研究开发项目(科工计[2007]825号)
中国矿业大学深部岩土力学与地下工程国家重点实验室开放基金项目(SKLGDUEK1012)
福建省自然科学基金项目(2011J01317)
关键词
岩石动力学
应力波
多条节理
非线性变形
透射系数
rock dynamics
stress wave
multi-fracture
nonlinear deformation
transmitted coefficient
