开滦钱家营矿1495E疑似陷落柱探查及综合治理     

李风志 《中国煤炭地质》2014,(6):38-41

岩溶陷落柱在我国华北石炭二叠纪煤系地层中广为分布,由于陷落柱贯穿于岩溶发育的奥灰和煤系地层之间,即使陷落柱在天然条件下不导水,但由于后期开采活动对其导水性能的改造,陷落柱往往成为奥灰与煤系地层之间联系的通道,井巷或采煤工作面一旦接近或揭露陷落柱时,可能产生突水,破坏采区划分秩序,严重影响煤矿安全生产。2009年,钱家营矿业公司在1495E风道掘进过程中首次揭露地质异常体,高度怀疑为岩溶陷落柱。该公司采取地面微动地震探测、井下直流电法和井下瞬变电磁等多种物探手段与现场钻探相结合,对地质异常体实际赋存状况进行探查。结果表明,该异常体不含水。但考虑到对物探成果必要的检验以及后续井巷工程和相邻工作面回采对异常体围岩应力平衡的破坏导致可能突水,矿方对异常体实施了钻探探查、建立密闭墙以及异常体注浆治理。治理方案的实施为矿山生产建设顺利展开奠定了基础,保证了工作面、采区科学合理划分,且为同行提供了借鉴经验。  相似文献   

淮北矿区刘桥一矿含水层水化学特征研究     

程乔  胡宝林  郑凯歌  杨华泽  刘兵昌 《中国煤炭地质》2014,(6):42-45,55

为了研究刘桥一矿含水层水化学特征,在分析矿区水文地质条件的基础上,对各个含水层投产前后水质动态变化进行详细研究,并将各含水层中的矿化度、总硬度以及阴阳离子所占的比例进行对比。结果表明,随着出水时间的增加,出水点水样中Na++K+和SO42-平均含量在逐渐减少,Mg2+有所增加,Ca2+和HCO3-变化不大;总硬度和总矿化度表现出不同程度的降低。最后,从突水点水样分析结果和附近的太灰、八含长观孔的水位变化情况,推测出太灰水和八含水联系紧密,也是6煤层底板的主要突水水源。  相似文献   

深部煤矿地下水温对矿井涌水量预计的影响     

刘汉湖  ;李秀晗  ;姜振泉  ;曹丁涛  ;孟凡贞 《中国煤炭地质》2014,(7):42-44

随着我国煤矿开采深度增加,地温、含水层水温升高,相应地含水层渗透系数增大,渗透系数的变化会对矿井涌水量产生一定影响。矿井勘探时期对该问题重视不够。以赵楼煤矿为例,考虑地下水温对渗透系数影响,采用解析法预计了矿井正常涌水量,预计结果为398.53m3/h,与不考虑地下水温变化情况相比较,增加59.63m3/h,增加幅度为17.60%,表明地下水温是影响深部煤矿矿井涌水量的重要因素。  相似文献   

Growth-rate-dependent prediction of pile set-up and its application in driven pile foundation construction     

Jay X. Wang 《Geomechanics and Geoengineering》2017,12(2):86-106

In this paper research was presented on the development of a growth-rate-dependent model for pile set-up prediction using the restrike and static/statnamic load testing data collected from different projects. The data included: a) restrike records from ninety-five production piles and restrike and load test results of nine instrumented piles driven in soft clays from the relocation project of Highway No. 1 in Louisiana (LA-1); and b) restrike and static load testing data of five fully instrumented square PPC piles driven at four different bridge sites in various soil layers from sands to clays in Florida. Research effort was focused on the prediction of the ultimate shaft resistances with pile set-up formulated using the pile resistance growth rate-dependent model. The timeframe of interest was studied for a practical set-up magnitude such as 90% of the ultimate shaft resistance (Q₉₀). As an application of the rate-dependent model, it was found that piles at the LA-1 relocation project, in general, reached about 95% of the ultimate shaft resistances at the time of 2 weeks after pile installation. The strategy of incorporation of pile set-up in adjusting pile driving criteria or/and design during pile construction, such as the experience-based plan of a two-week waiting period adopted by Louisiana DOTD, was investigated and justified.  相似文献   

Research on shaft resistance of rock-socketed piles based on the cavity expansion theory     

Haofeng Xing  Feng Xiong  Lujie Wang  Yong Luo 《Marine Georesources & Geotechnology》2017,35(6):873-877

The shaft resistance of rock-socketed piles depends not only on the properties of its surrounding rock, but also on the radial force induced by the load imposed on the top of the pile. This paper deduced a plastic zone of rock around a single pile and obtained the shaft resistance of a rock-socketed pile based on the theories of cavity expansion and shear strength. The research results showed that the magnitude of the radial force in the socketed portion of a rock-socketed pile was related to the pile diameter, Poisson’s ratio, and properties of the surrounding rock. The influence area of rock decreased with increasing pile diameter. The radial force and lateral friction decreased with the increasing relative stiffnesses of the pile and rock. The radial stress on the elastic–plastic interface can be analytically determined based on the rock properties and depth. A field test was used to validate the proposed method, and a good agreement was obtained between the field data and predicted results of the proposed method. The research results in this paper are beneficial to guide actual practice.  相似文献   

地下水位下降对井壁破坏的影响     

许光泉  刑军  吕杰堂 《煤田地质与勘探》1999,27(3):36-39

淮北某些矿区井筒变形、破坏严重,其主要诱发因素是下含水层水位下降而产生的附加应力。运用[2D-σ]软件进行了数值模拟认为:由于地下水位下降,地层与井筒发生相对位移而产生剪应力,其大小与水位降深和相对位移成正比;轴向应力随深度变化小,而随下含水层水位下降而增大;井壁破坏首先发生在其内缘,并逐渐向外扩展,破坏度沿深度方向增大;一含和下含同时有水位降时,轴向应力和剪应力的变化与单一含水层水位下降时相似,但轴向应力变化幅度明显增大,剪应力在上部含水层处增加。模拟计算分析结果与淮北地区井壁变形、破坏情况大体一致。   相似文献   

水介质爆破拆除地下桩体的实践   总被引：1，自引：0，他引：1       下载免费PDF全文

白聚波 《探矿工程》1999,(4):54-55

介绍了地下钢筋混凝土桩的控制爆破方法,以及在钻孔设备及外界约束较特殊的情况下,钻孔、装药及起爆等方面的注意事项。  相似文献   

地面注浆封堵松散层段井筒涌水     

吴昌文 《煤田地质与勘探》1997,25(1):40-43

芦岭煤矿南风井巨厚松散层段井筒涌水,采用地面注浆堵水方法获得成功。本文着重介绍地面注浆堵水钻孔布置、注浆参数选择及工艺系统。   相似文献   

下保护层开采上覆煤层产气机理及规律     

赵龙  降文萍 《中国煤炭地质》2020,(1):73-78

通过理论研究分析了采动区煤层裂隙特征、煤层气赋存特征和煤层气运移特征,揭示了煤矿采动影响下上覆被保护煤层产气机理。分析认为采动区煤层产气机理与常规煤层气产气机理不同,一是采动区煤层基质孔隙大、内部裂隙多、离层裂隙发育。二是采动区煤层气解吸快、解吸量大、水中溶解气少。三是采动区煤层气运移以气体单向流为主,评价渗透性指标为透气性系数。在收集大量采动区煤层气井产气数据的基础上,研究了产气机理对产气规律的影响。采动区煤层气井产气规律与常规煤层气井相比,具有产量提升快、产气峰值高的特点,整体呈现先迅速增大后逐渐减小趋于平稳的规律。结合采动区煤层产气机理研究,分析认为气产量提升速度快是由于煤层裂隙迅速增多且气体在裂隙中以气相单相流运移为主,产气峰值高是由于储层压力快速下降使煤层气加速解吸,短时间内在井筒附近聚集大量游离气。  相似文献