【摘要】 在块体离散元面–面接触的基础上,给出不同尺度结构面的计算方法,建立离散元对岩土爆破模拟的计算模型,实现块体自分裂计算程序,在药包附近采用小尺度块体,远区采用大尺度块体,可以更为准确地描述爆破载荷下岩体结构面的尺寸效应。新的计算方法增加不同尺度结构面之间的计算方法,用其模拟岩土中的爆破问题可以得到:(1)通过模拟近区岩体内的应力场和位移场,得到爆源近区岩体在动载荷下的破坏特征,与单个尺度岩体结构面的计算程序相比,可以更准确体现结构面破坏引起的能量耗散对近区应力场的影响。(2)模拟的鼓包、爆破漏斗等岩土爆破现象可以很好地吻合经验公式,说明该计算方法不仅能反映小时间尺度上爆炸现象,如近区的应力场,还可以反映大时间尺度上的爆炸现象。更多还原

【Abstract】 The new calculation method of structural surfaces with different scales is given on the basis of block discrete element method(DEM) in which contacts face to face.Moreover,a new discrete element model for simulating rock and soil blasting problem is built.The elements of new model can be split by itself in the program.There are small scale blocks around the charge,and large scale blocks are adopted in far zone.And the new calculation method between different scale structural surfaces is added in the model.So it can depict the scale effect of structural surface in rock mass more accuracy.In addition,some stimulated examples of rock blasting are showed by the new calculation method.The following two rules can be gotten from these examples.(1) The destruction characteristic of rock mass near the charge is obtained by simulating the stress and strain fields.Comparing it with the results obtained from the primary block discrete element method,it can represent the effects of the breakage of rock mass around charge on stress fields in near area.(2) For some rock and soil phenomena,such as blasting crater and drum,the simulated results by the new model can fit well with the experimental formula.更多还原