Experimental Study On The Stress Distribution And Crack Propagation Model Of Circumferential Slit Colum

In the blasting engineering,it is usually required that the blasting construction can meet the rock breaking block degree to facilitate the mechanical shipment,and it can form a smooth and flat rupture surface meeting the technical requirements.The traditional blasting technology includes smooth blasting and pre-cracking blasting.However,these two blasting techniques have some defects.At present,the directional fracture blasting technology can well meet the above blasting requirements.Among them,the slitting blasting technology is widely used in the actual engineering of directional fracture blasting with its convenient construction technology and low construction cost.Based on the theory of blasting mechanics,the paper studies the stress field distribution and crack forming of the circumferential slitting package explosion,and uses the ultra-dynamic strain gauge,the core slicing treatment and the engineering acoustic wave ct detection analyzer to detect the ring.The distribution of the rupture blasting stress field distribution of the slitting package was studied and analyzed.The crack distribution after the blasting of the specimen was observed,and the causes of crack formation and expansion were analyzed.The damage of the specimen was further confirmed by the damage of the specimen.The results are as follows:Whether in the horizontal direction or the vertical direction,the stress peak at the direction of the slit is larger than that at other places.At the same distance,the stress peak at the slit is more than the back-to-cut The peak value of the stress at the joint is 4.78%-33.51%.The increase of the number of slits will increase the peak value of the compressive stress of the rock at the slit and increase the duration of the peak stress,which is conducive to rock cracking.The specimen forms a strip after blasting.The circumferential fracture crack corresponds to the position of the slit of the grain column,which confirms the effect of the directed fracture blasting of the circumferential slitting pack.Figure[47]Table[7]Reference[50]...