The Study On The Change Rule Of Slope Stability Based On Blasting Cumulative Damage

The disturbance and damage of adjacent slope caused by blasting excavation,especially the accumulative damage caused by multiple blasting,will inevitably lead to the weakening of rock mechanics parameters and the reduction of rock integrity,which is an important factor causing the failure of slope.As for the study of the slope stability under blasting loading,formers mainly study the change law of slope displacement,velocity,etc.through the slope dynamic response under blasting load,or analyze the weakening law of slope rock mass by blasting damage.However,when it comes to the combination of the two to analyze the change of the safety factor of slope under blasting cumulative damage,the research is less.According to the damage model,the cumulative damage effect of rock slope under blasting load is studied by using the method of sonic wave test,which is used to reduce the shear strength parameters of the slope mass.Based on the strength reduction method and time history analysis method,the change law of slope safety factor under blasting load is studied by using finite element software ANSYS.The results show that,under the current condition of blasting,the safety factor of slope is reduced by 5.1%~12.6% under each blasting load,and the reduction of slope safety factor caused by each blasting damage is between 2.91% and 8.38%.In the end of the whole experiment,the safety factor of the slope is decreased by 35.2% because of the cumulative damage.As we can see,the effect of blasting damage on the safety factor of the slope is greater than that of the blasting load.The influence of blasting vibration on weak slope is more obvious.In addition,according to the change law of the safety factor under the blasting method of several times,the influence of the blasting vibration on the stability of the weak side slope is more obvious.