土体的总应力抗剪强度指标为c、,有效应力抗剪强度指标为c\'、,则其剪切破坏 时实际破裂面与大主应力作用面的夹角为 。

A、.45°+<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/14844084761496c91dadc9c70423e9b78d3e8e078c2f8image4.png">

B、45°-<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/14844084762045d04f8cae6a045d589202ae75227de8aimage4.png">

C、45°+<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/1484408476277c6a890bc66e34a66a5ad38f2e9ccc0a9image5.png">

D、45°-<img src="https://s3.cn-north-1.amazonaws.com.cn/qingshuxuetang/examination/imgUplod/1484408476342420dd7dd0a274d46ad91dfe78f3efc22image6.png">