Dynamic Response Of Slope Under The Action Of Oblique Incidence Seismic Wave

Considering the oblique incidence in the dynamic analysis of slopes,and based on the FLAC3 D software,a obliquely incident method is proposed in this study,and 3 simulation models with different slope angles are built,the slope angles are 30°,45°,and 60°,respectively.The El Centro earthquake records were utilized in this study to excite the models slopes,and the influence of the incident angle on the dynamic response of slope was studied.The following conclusions can be drawn:(1)According to the mechanics condition of the FLAC3 D,based on the boundary decomposition and wave field decomposition in the slope,the obliquely incident can be realized.(2)The analysis of slope acceleration response shows that as for the slope with slope angle of 30°,the acceleration amplification coefficients at slope top increase first and then decrease with increasing incident angle.As for the slope with angle of 45° and 60°,the acceleration amplification coefficients at slope top increase with increasing incident angle,and the acceleration amplification coefficients under obliquely incident are significantly larger than those under the vertical incident.The acceleration amplification coefficients at slope top under the obliquely incident are obviously larger than 3,implying that the influence of the incident angle on the dynamic response of slope cannot be ignored.(3)The analysis of slope surface displacement shows that when the slope angle is 30°,the slope surface displacement under obliquely incident with incident angle of 30° is slightly larger than that under the vertical incident,and all are much smaller than that under the obliquely incident with incident angle of 10° and 20°.When the slope angle is 45°,the slope surface increases with increasing incident angle.When the slope angle is 60°,if the input amplitude is large,the surface displace at slope top increases with increasing incident angle;if the input amplitude is small,the surface displace at slope top increases first and then decreases with increasing incident angle.(4)The analysis of stress condition in the slope shows that with regards to the slope with slope angle of 30°,the stress condition in the slope mass is very complex.When the slope angle becomes 45°,mainly shear stress is observed in the slope mass and only a little tensionstress is observed near the slope surface,the same stress condition in the slope mass is obtained when the incident angle is 10°.When the incident angle becomes 10° and 20°,the number of the nodes with tension stress increases obviously,and many nodes near the slope surface suffer shear stress and tension stress simultaneously.As for the slope with slope angle of 60°,when the slope angle is 10° and 20°,the nodes near the slope surface,especially near the slope toe,suffer much tension stress,still the seismic exaction finishes.When the incident angle is 30°,the stress condition in the slope mass is significantly different from that under the obliquely incident with incident angle of 10° and 20°,the slope mass mainly suffers the shear stress,however,many nodes near the slope top suffer tension stress.