摘要：岩体强度与裂隙参数是反映工程岩体质量的基本参数,其准确获取是进行地下工程围岩分级与支护合理设计优化的前提。传统的岩体强度测试方法需要对现场围岩取芯并运至实验室测试,测试结果难以反映工程现场环境下的岩体力学性质,而对于岩体强度与裂隙参数的原位测试方法研究较少。本文基于能量守恒定律,建立了岩石切削能密度与随钻参数的关系式,构建了岩体等效强度随钻反演模型(ES-DP模型),系统开展了岩体数字钻进试验。结果表明,相对于传统测试方法,岩体等效强度随钻测试结果平均差异率为2.4%,验证了ES-DP模型对岩体等效强度测试的有效性。在此基础上,建立了岩体裂隙参数随钻识别模型,与实际测量结果相比,该模型测得的岩体裂隙位置与宽度平均精度分别为1.8和1.6 mm,测试精度较高。基于上述研究,本文提出了一种岩体强度-裂隙随钻识别方法,为实现地下工程围岩强度参数与结构特征的原位实时测试提供了新方法。

摘要：薄煤层N00工法的提出,革新了传统的煤矿开采模式、关键技术与装备系统,并取得了成功应用。而新开采模式下的巷道围岩控制技术尚不完善,为实现薄煤层N00工法巷道顶板结构的安全稳定,考虑其工艺流程和顶板变形特点,将巷道划分为超前硐室、垮落成巷两个阶段。并基于Hoek-Brown非线性岩体强度破坏准则,确定了巷道顶板不同阶段的锚杆/索预紧力的计算公式,提出了巷道顶板锚杆/索预紧力及长度设计方法。此外,结合数值模拟研究了不同阶段巷道顶板锚杆/索支护作用机理及不同锚杆/索支护组合对围岩应力分布的影响,揭示了锚杆/索支护关键参数对顶板稳定性的影响机制。最后,综合理论与数值模拟分析结果,提出了分区补偿支护技术,确定了锚杆/索预紧力、长度及选材的设计原则,该技术在现场取得了良好的应用效果。

摘要：Ground stress is the fundamental cause of deformation and failure during underground structural engi- neering. Field stress measurements in the main coal bed in the Lüliang mining area were made by the bore hole, stress relief method. From these data the ground stress distribution of the mining area was obtained. The relationship between the horizontal principal stress and the deformation and failure of a roadway is discussed with an engineering example. The results indicate that horizontal stress dominates in the shallow crust in the Lüliang mining area. Roadways at different angles to the maximum principal stress have different levels of stress concentration. This leads to a significant difference in stability of the corresponding roadways. These research results provide an important criterion for determining roadway position and direction, stope layout, and roadway support design.

摘要：氡气是深部地下洞室建设过程中岩石破裂产生的污染性、放射性气体,深部岩体在高应力下普遍发生剪切破裂,然而,氡气释放量与岩石剪切破裂演化的相关性尚不清晰。针对这一问题,分析了完整锦屏大理岩和白鹤滩玄武岩两类岩石的放射性核素活度。自主设计了完整岩石直接剪切试验系统,并同步测量岩石破裂过程中的氡释放量。讨论了岩石剪切破裂面表面积与累积氡浓度的相关性。试验结果表明,在法向荷载相同的条件下,岩石中氡释放量随剪切位移的增大而变化,总体呈现在加载初期略有增加后小幅回落,再大幅增加至峰值释放水平,试样破坏后随着剪切位移的发展下降至稳定水平的规律。随着法向荷载的升高,初始氡浓度和峰值氡浓度均呈线性增长的趋势。通过对声发射特征参数RA-AF分布的研究,发现岩石剪切破裂面表面积与累积氡浓度具有相似的发展变化趋势。岩石剪切破裂过程中氡释放规律的揭示对深部工程排氡/隔氡设计具有重要指导意义。

摘要：The influence of an upper,mined coal seam on the stability of rock surrounding a roadway in a lower coal seam is *** technical problems of roadway control are discussed based on the geological conditions existing in the Liyazhuang Mine No.2 coal *** stress distribution and floor failure in the lower works after mining the upper coal is studied through numerical *** failure mechanism of the roof and walls of a roadway located in the lower coal seam is *** predicted deformation and failure of the roadway for different distances between the two coal seams are used to design two ways of supporting the lower *** is a combined support consisting of anchors with a joist steel tent and a combined anchor truss.A field test of the design was performed to good *** results have significance for the design of supports for roadways located in similar conditions.

摘要：In the context of a room-and-pillar mining gob in Shanxi province in China,this paper numerically investigates the stress distribution and deformation rules of roadway surrounding rocks at various locations of residual coal pillars in room-and-pillar mining gobs using software FLAC3 *** is found that the concentrated stress beneath coal pillars distributes in a shape of ellipse.A reasonable roadway layout is then *** this design,it is indicated that roadways should be designed to avoid the supporting zones of pillars with increasing compression and take into account the roof falling and crushing in the upper *** to the surrounding rock deformation characteristics and mining roadway locations as well as the supporting principles of timely support,rock reinforcing,piecewise management and suiting local conditions,a new asymmetric shield supporting plan is *** field surveying results show that this supporting plan can effectively control the roadway rock deformation,thus guarantee the safe and smooth construction of roadways.

摘要：Aiming at soft rock ground support issues under conditions of high stress and long-term water immersion, the ground failure mechanism is revealed by taking the deep-water sumps of Jiulong Mine as the engineering background and employing field investigation, tests of rock structure, mechanical properties and mineral composition. The main factors leading to the surrounding rock failure include the high and complex stress state of the water sumps, high-clay content and water-weakened rock, and the unreasonable support design. In this paper, the broken and fractured rock mass near roadway opening is considered as ground small-structure, and deep stable rock mass as ground large-structure. A support technology focusing on cutting off the water, strengthening the small structure of the rock and transferring the large structure of the rock is proposed. The proposed support technology of interconnecting the large and small structures, based on high-strength bolts, high-stiffness shotcrete layer plugging water,strengthening the small structure with deep-hole grouting and shallow-hole grouting, highpretensioned cables tensioned twice to make the large and small structures bearing the pressure evenly,channel-steel and high-pretensioned cables are used to control floor heave. The numerical simulation and field test show that this support system can control the rock deformation of the water sumps and provide technical support to similar roadway support designs.

摘要：A new composite two component grout comprised of modified urea-formaldehyde resin and cement was formulated to take account of the advantages and disadvantages of both the cement grout and the chemical *** new grout is designed for water blocking by reinforcing as well as seepage control by bore *** A component consists of a modified urea-formaldehyde resin A component,some cement,and some *** B component is an alkaline *** orthogonal test of four factors at three levels showed that gel time increased with increased water content and with urea-formaldehyde resin *** time decreased at increased levels of alkaline *** A component of this new composite grout is stable over time.A mixed cross-over test showed that as the volume ratio of A to B increases the gel time falls at first but then *** solid strength decreases with increasing levels of the B *** solid strength increases over time and becomes stable by the 28th day after *** viscosity increases with increasing levels of resin A *** increase is exponential and may be fit to:l = 8.162e0.0286x.

摘要：In order to define the development direction of safe blasting technology in high-temperature coal seams in China, this paper presents a systematic, state-of-the-art review on safe blasting technology. Information such as high-temperature coal fire extinguishment and cooling, anti-high-temperature blasting supplies, heat insulation blasting setting, operation procedures for high-temperature blasting, and so on, are presented. Analysis shows that the development of effective technology for coal seam fire extinguishing and cooling, the manufacture of anti-high-temperature blasting supplies, especially priming materials, the development of heat insulation blasting setting, and the establishment of technical specifications suit large-scale blasting design and construction work at high-temperature coal seams, are the essential methods for safe blasting at high temperature coal seams.

摘要：Based on the height of back-filled materials,thickness of ore body,height of boundary pillar and dipping angle of ore body and water pressure,the safety factors of all the pillars are calculated with the limit equilibrium *** calculation results present that the safety factors of pillars in Sections 19,20,24,28 are less than 1.3,and those of unstable sections are identified ***,a numerical investigation in Sections 18,20,22,24,25 and 28 implemented with numerical code RFPA2D is employed to further validate the pillar performance and the stability of *** numerical results show the pillars in Sections 18,22 and 24 are stable and the designed pillar size is *** width of the ore body near Section 28 averages 20 m,failure occurs in the left stope,but the boundary pillars near Section 28 maintain good *** pillars in Sections 20 and 25 are unstable which are mainly affected by the Faults F8 and *** existence of faults alters the stress distribution,failure mode and water inrush *** work provides a meaningful standard for boundary pillar and stope design in a mine as it transitions from an open pit to underground.