摘要
花岗岩残积土边坡存在较为发育的微裂隙结构面和一些软弱岩脉风化而成的软弱夹层,由于风化作用、降雨和地下水渗入等外界环境影响,裂隙中的填充物泥化和膨胀,结构面的抗剪强度迅速下降,造成边坡失稳破坏。通过对边坡破坏形式和机理的研究,得到了微裂隙引起边坡破坏的两个内外因素,外因是开挖导致裂隙处应力集中形成塑性破坏区;内因是裂隙处土体具有峰值—残余强度差异。以某含软弱夹层花岗岩残积土边坡为例,建立有限元数值模型对该边坡的变形特征进行研究,发现软弱夹层的存在不仅造成了边坡总体变形的增大,还决定了边坡失稳破坏时滑动面的位置。
Granite residual soil slope exists developmental structure surface of microcracks and weak interlayers from weathering of some weak dyke,fillers in cracks are in the mud and inflation due to the external environment influence,such as weathering,rainfall and groundwater infiltration.. Meanwhile,shear strength of the structure drops rapidly,which cause the instability and failure of slope. Through studying the research on the failure modes and mechanism of soil slope,the microcracks found to be resulted in both inside and outside factors of it. External cause is that the excavation which lead to stress concentration in cracks place where become the plastic zone; Internal cause is the differences between peak and residual strength of soil in cracks. Taking a granite residual soil slope with weak interlayer as an example,the finite element numerical model is established to study the deformation characteristics of slope. It is shown that the existence of weak interlayer not only causes the overall deformation of the slope increases,also determines the position of sliding surface.
出处
《中国地质灾害与防治学报》
CSCD
2015年第1期23-30,共8页
The Chinese Journal of Geological Hazard and Control
基金
福建省地质灾害重点实验室开放基金(FJKLGP2012K001)
关键词
花岗岩残积土
微裂隙
软弱夹层
应力集中
稳定性
granite residual soil
microcracks
weak interlayers
stress concentration
stablity
