SENSITIVITY OF TIME FOR STRESS EQUILIBRIUM TO WAVE IMPEDANCE RATIO WITH DIFFERENT RISING TIMES IN SHPB TESTS
PING Qi1，2，MA Qinyong1，2，YUAN Pu1
(1. Engineering Research Center of Mine Underground Projects，Ministry of Education，Anhui University of Science and Technology，Huainan，Anhui 232001，China；2. Key Laboratory for Coal Mine Safety and Efficient Exploitation Jointly Built by Anhui Province and Ministry of Education，Anhui University of Science and Technology，Huainan，Anhui 232001，China)
Abstract：Rectangular wave，trapezoidal wave and sloping wave were expressed as trapezoidal wave with different rising times to analyze the sensitivity of time for stress equilibrium to wave impedance ratio in split Hopkinson pressure bar(SHPB) tests. Based on one-dimensional stress wave theory，propagation of incident stress wave in specimen，was analyzed and related calculation formulas for stress distribution along loading direction were obtained under trapezoidal wave with different rising times. Variation curves of time for stress equilibrium and stress uniformity were calculated under trapezoidal wave with different rising times and different specimen-bar wave impedance ratios. Several trapezoidal wave parameters affecting time for stress equilibrium and stress uniformity，such as rising time and specimen-bar wave impedance ratio，were studied；and some useful conclusions were also obtained. Research results can provide a theoretical basis for SHPB experimental designs and related analyses.
平 琦1，2，马芹永1，2，袁 璞1. SHPB试验中不同加载升时应力平衡时间对波阻抗比的敏感性[J]. 岩石力学与工程学报, 2013, 32(10): 2128-2134.
PING Qi1，2，MA Qinyong1，2，YUAN Pu1. SENSITIVITY OF TIME FOR STRESS EQUILIBRIUM TO WAVE IMPEDANCE RATIO WITH DIFFERENT RISING TIMES IN SHPB TESTS. , 2013, 32(10): 2128-2134.
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2013, Vol. 32 
