Analysis of the Incipient Failure During Outburst of Coal and Gas

针对煤矿煤与瓦斯突出动力现象的复杂过程,对突出启动前煤体的初次破坏特征进行了分析。特别是对影响突出发生的煤体初次破坏的几何特征以及层裂拱壳形成的力学原理,通过简化的力学模型做了分析,同时讨论了影响初次破坏特性的主要因素,包括与不同煤体结构相适应的煤体材料不同破坏准则的影响。为进一步认识煤与瓦斯突出的机理,突出的启动、发展演化提供一种思路,进而为突出的预测和防治提供基础

Simulation of Vibration Caused by Blasting for a Layered Slope

Recent studies showed that vibration caused by blasting mainly reflects the property of geological structure itself neighboring the blasting center. Different vibration signals can be collected for different geological structures under blasting. Hence, vibration signal can be used to identify geological structure, especial for a slope with a weak layer. As the geological structure for a practical slope is usually complicated, the simulation of vibration caused by blasting should be carried out first. Generally, the material in a certain zone near the blasting center will undergo damage, so the physical model to simulate this region is the most concerned. In this paper, the damaged zone near blasting center is neglected, and the blasting load can be considered being applied on the interface between the damaged zone and undamaged zone. Regarding the relations between the weight of explosive, the size of damaged zone, and the dynamic loading to propagate out away, the vibration caused by blasting for a practical layered slope is simulated. Compared with the measured signal in site, it can be seen that the simulating result is in well agreement with that of practical testing. The results also indicate that the farther the testing point apart from the blasting center, the more accurate the simulation is

MECHANISM OF PROGRESSIVE FAILURE OF A KIND OF FAULTED ROCK SLOPE DUE TO SLIP-WEAKENING

含裂隙的岩土材料在剪切作用下,随着剪应变的增加,裂纹端部一定区域内的强度会表现出滑动弱化的现象.岩土材料这种性质的变化不同于粘性土结构性破坏,也不同于剪胀.在一定的载荷作用下,坡体内裂隙端部的滑动弱化使坡体内的应力重新分配,从而使得应力集中加剧,裂隙尖端进一步扩展,造成岩体结构性的破坏,乃至整个滑面的贯通直至发生滑坡.因此,滑动弱化是一类含裂隙岩质边坡滑坡的机理

地应力随钻测量装置及方法

本发明公开了一种地应力随钻测量装置，包括钻机、钻杆和钻头，与钻头相连的钻杆上靠近钻头的侧壁上设有压力传感器，钻杆上还设有保护压力传感器的滑盖，滑盖通过驱动装置来实现滑开与关闭。本发明还公开了一种地应力随钻测量方法，包括如下步骤：选择需要测量的位置，用地应力随钻测量装置施工钻孔；钻完孔后停机，使钻杆与钻机脱离，再将压力传感器直接连接信号处理装置，然后通过滑盖驱动装置使滑盖滑开露出压力传感器；通过压力传感器测量煤层的地应力。本发明可随时停钻进行地应力测量，可方便地在井下使用，能够在一个测量孔中连续测量、测量准确且时间短，并能够测量软煤层的地应力

EXTENSION OF THREE-DIMENSIONAL SIMPLIFIED JANBU'S METHOD FOR SLOPE STABILITY ANALYSIS

对三维简化的Janbu法进行了扩展,使得离散后在同一行上的各条块在水平横向的安全系数相等以及在同一列上的条块在水平纵向的安全系数相等,得到不同行(列)的安全系数,最后通过各条块底滑面的几何特性与受力分析给出其独立的安全系数以及各条块潜在的滑动方向.该方法拓展了传统极限平衡方法只给出坡体总体安全系数的思路,可对坡体局部稳定性和潜在滑动方向进行判定.该方法可适用于任意形状的滑面,还可分析包括考虑孔隙水压力、地质体分层、上覆载荷以及地震力等其他形式的外载

煤层气参数的简便随钻测量装置及方法

本发明公开了一种煤层气参数的简便随钻测量装置，包括钻杆和钻头，所述钻杆的侧壁上集中设有多个供煤层气通过的通孔，所述钻杆的后部连接有测量煤层气参数的仪器仪表。一种煤层气参数的简便随钻测量方法，包括如下步骤：在井下工作面选择需要测量的位置，用钻机驱动煤层气参数的简便随钻测量装置施工钻孔；钻完孔后停机，使钻杆与钻机脱离，再将钻杆的后部直接连接煤层气参数测量仪器仪表；钻杆的后部出口由煤层气参数测量仪器仪表直接封闭，经过一定时间后，使钻杆内部的气体压力达到稳定后，通过煤层气参数测量仪器仪表测量煤层气参数。本发明能够提高测量精度，操作简便、测量时间短，能够实现随钻连续测量

水位涨落引起分层边坡滑坡的机理

本文基于分层边坡在水位涨落时发生滑坡的模拟实验,简要描述了实验中的主要现象,计算了实验模拟的分层坡体内与水位变化直接相关的动态渗流场、孔隙水压力场与渗透速度场分布.根据计算结果,对水位变化导致坡体变形失稳的机理进行了分析,为这类分层边坡滑坡的治理提供了依据

3D Anisotropic Elastoplastic-Damage Model and its Application in Simulating the Behavior of Rock Materials

A 3D anisotropic elastoplastic-damage model was presented based on continuum damage mechanics theory. In this model, the tensor decomposition technique is employed. Combined with the plastic yield rule and damage evolution, the stress tensor in incremental format is obtained. The derivate eigenmodes in the proposed model are assumed to be related with the uniaxial behavior of the rock material. Each eigenmode has a corresponding damage variable due to the fact that damage is a function of the magnitude of the eigenstrain. Within an eigenmodes, different damage evolution can be used for tensile and compressive loadings. This model was also developed into finite element code in explicit format, and the code was integrated into the well-known computational environment ABAQUS using the ABAQUS/Explicit Solver. Numerical simulation of an uniaxial compressive test for a rock sample is used to examine the performance of the proposed model, and the progressive failure process of the rock sample is unveiled

A NEW MODEL FOR FATIGUE LIFE ESTIMATION BASED ON THE TOTAL CYCLIC STRAIN ENERGY

从总循环应变能的角度出发,提出了一个新的疲劳寿命计算模型,通过对30CrMnSiA钢和AISI4340钢两种材料的的疲劳寿命计算,并与相关实验数据对比,证明了该模型计算疲劳寿命较为准确