The major reason of the failure of jointed rock-mass is the formation of the plastic zone near the crack
tip of I-II mixed crack which leads to the growth, propagation of the branched crack under load condition. In
the paper, the failure judgment of mini-plastic zone’s displacement is derived by the Mises yielding rule. The
anchor cable is simulated by the different link elements and inflicting pre-strains according to the difference of
mechanism of the consolidated segment and free segment. The stress and strain fields near crack tip of twain
collinear cracks of different angles and consolidated conditions are simulated by iso-parametric element with eight
nodes. The iso-parametric element with eight nodes is degenerated to singular element at crick tip to simulate
crack. It is shown that the mini plastic zone’s displacement near the crack tip begins to increase, then decreases
with the increase of the angle of the crack. The better consolidated condition is, the smaller the angle of crack
tip is when the mini plastic zone’s displacement near the crack tip arrives at the biggest value. The mini plastic
zone’s displacement near the crack Tip 2 is bigger than that near the crack Tip 3. The crack is easier to failure
with the increase of load.
WANG Zhong-chang1,2* (王忠昶), ZHAO De-shen2 (赵德深), WU Hui-jun1 (吴会军)
. Study on Toughening on Crack Prevention of Jointed Rock Masses
with Different Pre-Stress Anchor Cables[J]. Journal of Shanghai Jiaotong University(Science), 2012
, 17(5)
: 552
-558
.
DOI: 10.1007/s12204-012-1324-7
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