单轴压缩条件下岩石破损过程的CT试验分析

采用工业计算机层析(ICT)设备与全数字液压实验系统EHF-EG200KN试验机,对大台煤矿冲击倾向性煤层底板岩石试样进行了单轴压缩荷载作用下的CT试验,得到了单轴压缩荷载作用下不同应力阶段岩石试样微裂纹发展的CT图像。通过对CT图像灰度值的分析,得到单轴压缩荷载作用下岩石的损伤破裂过程。为进一步研究煤层底板岩石的破坏及冲击地压的发生机理提供依据。     

岩爆灾害的灰类白化权函数聚类预测方法

岩爆是高应力岩石地下工程中的地质灾害.将岩爆与其影响因素之间的关系作为灰色系统,提出采用灰类白化权函数聚类的预测方法对岩爆灾害进行预测.选取岩石弹性能量指数、脆性系数和围岩最大切向应力与岩石单轴抗压强度的比值作为岩爆灾害预测的主要影响因子,并构造了适于岩爆预测的各聚类指标的白化权函数.采用本文提出的方法对国内外一些岩石地下工程实例进行了分析,并与工程实际情况进行了对比,研究结果表明,本文提出的基于灰类白化权函数聚类的岩爆灾害预测方法具有较高的预测精度.     

The Study of Outburst-proneness of Coal Seam Via Experiments and fuzzy Comprehensive Judgement

The four existing autburst-proneness indexes and a modified outburst energy index W were applied to study outburst-proneness of coal seam via exprements; the fuzzy mathematics method was used for fuzzy comprehensive judgement on outburst-proneness of coal seam;the results obtained in experiments were identical with engineering practice.     

Study on the Mechanism of Rockburst

Rockburst is often encountered in the underground engineerings of high geostress area, it is a kind of dynamic geodisaster.Depending on the examples of rockburst in the Erlang mountain highway tunnel and Jinping second powerstation tunnel, the fracture geometry shapes of rockburst are elaborated. Through the research of SEM analysis and rock mechanics tests of rockburst, three basic mechanics mechanisms of rockburst have been summarized,i.e., compression cracking, compression shear cracking,bending and breaking.     

Research Advance on Rockburst Theory and Its Engineering Application in Collieries

This paper summarizes and describes the progress in coal rockmass outburst theory in resent decades both at home and abroad,discusses the tendency of mechanism of rockburst,and gives a fullier review about the presently adopted prediction methods and preventive measures,simultaneously looks into the prospective development on the study of prediction and preventive measures and its practical applications.     

An Attribute Mathematical Model and Its Application in Predicting and Classifying Rockbursts

Based on attribute mathematical theory, an attribute recognition model to predict and classify rockbursts was established. Firstly, the main factors of rockburst, such as the maximum tangential stress of cavern walls σθ, uniaxial compressive strength σc, uniaxial tensile strength σt, and the elastic energy index of rockWet, were chosen for the analysis; and three factors, includingσθ/σc,σc/σt andWet, were chosen as the criterion indices for rockburst prediction in the proposed model. Secondly, attribute measurement functions were constructed to compute the attribute measurement of a single index. Thirdly, the index weight was determined by similar weights defined by similar figures. Finally, the possibility and classification of rockburst were recognized by the confidence criterion. A series of underground rock projects were assessed with the proposed model and method to verify the proposed model. The study indicates that the synthetic assessment results agree well with the practical records, and are coherent to those of the fuzzy synthetic evaluation model and the matter-elements model. Moreover, the proposed model was used to predict rockbursts of a hydropower station and Qinling Tunnel. The results are coherent to those of the synthetic evaluation method, such as artificial neural network and distance discriminant analysis method, and others. The research indicates that an attribute recognition model can predict and classify rockbursts in engineering projects deep underground and provides a new method in practice.     

Rockburst Hazard and Its Forcast and Treatments in Underground Engineering

Rockburst is a serious damage geologic hazard. According to the rockburst phenomenon in Erlangshan tunnel and the Jinping 2nd hydropower station and a large of rockburst data,this paper proposes that rockburst is a result that many factors synthesize. These factors include teconics ,epigenetic and superficial structure, wall-rock intensity, attitude of rocks, wall-rock state of stress, wall-rock deformation and underground engineering arrangement, etc. It is given that the mechanism of rockburst is a tension fracture damage under press.