TBM掘进隧洞回填固结灌浆施工的探讨

豆砾石回填灌浆和固结灌浆在引黄工程南干线长达90kmTBM施工中得到成功的应用。文中介绍了引黄工程南干线4^#-7^#隧洞豆砾石回填灌浆、特殊地质洞段的固结灌浆的灌浆设备、材料、浆液配比、压力、工艺等诸方面的现场施工情况。     

粘土作为高放废物处置回填材料的可行性研究

本文以西北粘土为对象,对其压实行为、热传导、膨胀特性,以及吸附和渗透性能进行了初步研究,借以探讨西北粘土在高放废物处置中用作回填材料的可行性。试验表明,以西北粘土为基材,经过适当的热改性和吸附改性,在初始含水量约为9%,于70MPa 下成型,用作高放废物处置中的回填材料是可行的。     

Mechanical analysis of roof stability under nonlinear compaction of solid backfill body

Based on the compaction characteristic test and the nonlinear compaction deformation characteristics of backfill material, this paper applies the theory of nonlinear elastic foundation of thin plate to establish a mechanical model of backfill body and roof in solid dense backfill coal mining. This study critically analyses the deflection equation of the roof by the energy method, derives the conditions of roof breakage and combined with concrete engineering practice analyses, determines roof movement regularity and stability in solid dense backfill mining. Analysis of the engineering practice of the 13,120 backfill panel of Pingmei 12# mine shows the theoretical maximum of roof convergence in backfill mining to be415 mm which is in significant agreement with the measured value. During the advancing process of solid backfill mining at the panel, the maximum tensile stress on the roof is less than its tensile strength which does not satisfy the conditions for roof breakage. Drilling results on the roof and ground pressure monitoring show that the integrity of roof is strong, which is consistent with the theoretical calculations described in this study. The results presented in the study provide a basis for further investigation into strata movement theory in solid dense backfill mining.     

Model test assessment of the generation of underground cavities and ground cave-ins by damaged sewer pipes

Ground cave-ins caused by damaged sewer pipes have been frequently reported in metropolitan areas and have caused severe socioeconomic losses. In this study, model experiments were conducted to determine how damaged sewer pipes generate ground cave-ins or cavities, with a focus on the influence of the soil type and density. Digital images of the model ground were captured to evaluate the internal deformation of the model grounds. Additionally, the vertical displacement at the surface, the size of the cavity, and the weight of the discharged soil were measured in each test. The results indicate that uniform soil with no fines content was more vulnerable to ground cavities than well-graded soil with fines content. Loose soil led to a ground cave-in with significant deformation over the entire model ground, whereas deformation was concentrated only on the ground cavities in the dense soil ground.     

神经网络在膏体充填质量模型中的应用

煤矿膏体充填质量受多因素影响,且具有非线性特性,用数理统计的方法直接建立充填质量模型很困难。为了减少试验次数、降低试验费用,通过神经网络建立的膏体材料充填质量模型明显优于传统的回归分析法,利用膏体充填材料塌落度与主要影响因素浓度、胶结料用量、细集料用量的关系模型,可以有效预测膏体充填材料的塌落度。     

绿色矿山经济效益核算理论与实证：以矿井充填开采技术为例

“双碳”目标背景下,如何加快推进绿色矿山建设是实现我国矿业转型升级与绿色发展、构建矿业新格局的关键。绿色矿山建设是一项复杂的系统工程,由于在勘察阶段、开发阶段、关闭阶段的资金投入巨大,加之矿山企业对绿色矿山内涵理解存在偏差、创建动力不足,使得我国绿色矿业体系的建设阻力很难消解。本文以微观企业为视角,依托于经济学生产函数和“成本-收益”情景分析,构建了基于“成本-收益”因子的绿色矿山经济效益核算方法,并以河北邢台矿区矸石充填开采技术为例,开展了绿色矿山经济效益核算的实证研究。研究结果表明,将2003—2021年间邢东煤矿矿产资源开发利用过程中的生态影响、社会影响,以及技术创新带来的产量增量同时纳入到绿色矿山经济效益“成本-收益”核算体系中,发现采用绿色开采方式——充填开采技术给企业额外带来的经济效益达24.61亿元,占矿山企业近20年综合收益的23%。本文研究对矿业绿色发展的路径选择和绿色矿业内生动力的深入挖掘提供理论与方法参考。     

不同灰砂比充填体侧限固结压缩试验研究

充填体在采场内由于被围岩包围,其力学性能与实验室单轴压缩条件下不同。为了研究采场充填体的力学性能及规律,提出了不同灰砂比充填体在侧限约束条件下的分级单轴压缩固结试验,分级压力为1kN(0.2 MPa)、2kN(0.4 MPa)、4kN(0.8 MPa)、8kN(1.6 MPa)、16kN(3.2 MPa)、32kN(6.4MPa)、64kN(12.8MPa)、128kN(25.6MPa)。试验结果表明:随着固结压力的增大,充填体压缩量呈线性增加,灰砂比对充填体压缩量影响不明显;固结应力与压缩率呈二次函数曲线关系;固结前后充填体的单轴抗压强度增加明显,28d龄期强度值增加幅度达24%以上。最后,采用SEM对充填体固结强化机理进行了分析。     

破碎围岩条件下预留矿柱开采对充填体稳定性的影响

为研究预留矿柱开采对其上部充填体稳定性的影响,结合某金矿矿岩赋存条件,采用考虑封闭系数的矿柱开采经验公式,提出开采尺寸为180 m×15 m×20 m（走向长度×高度×宽度）的矿柱开采方案。利用MAP3D软件对590~605 m水平间矿柱开采进行数值分析,结果表明：在一般原岩应力情况下,矿柱完全开采后上部充填体仍保持稳定;在较差原岩应力情况下,矿柱完全开采后上部充填体受压作用明显,可能发生失稳破坏。应用极限平衡方程对矿柱开采经验公式进行修正,提出通过减小采场跨度及加强支护的方式,降低对充填体单轴抗压强度的要求,能保证预留矿柱的安全回采和上部充填体的稳定。研究结果可为其他类似矿山提供设计思路。     

中低放废物陆地浅埋处置类似物—古墓葬的研究

本文将我国古墓葬和中低放废物陆地浅埋处置在选址、工程结构、设计原理和施工方法等方面进行了类比分析。分析结果表明，我国古墓葬对中低放废物陆地浅埋处置是很好的类似物，古墓及其随葬品长期保存的完好性说明了选择适宜的场址、合理的工程结构和良好的回填材料及科学的施工方法后，中低放废物陆地浅埋处置是安全的。对我国２个墓葬回填材料的测试结果表明，古墓葬材料具有良好的抗渗性，其渗透系数为１．５×１０￣（－８）ｃｍ／ｓ，对Ｃｏ和Ｃｓ吸附能力很强，分配系数分别为１．２×１０￣４和２．１×１０￣４ｍＬ／ｇ，延迟系数分别为４．４×１０￣４和７．７×１０￣４；这些材料良好的性能保证了古墓寿命的长期性，可考虑作为中低放废物陆地浅埋处置工程中的回填材料。     

万家寨引黄工程黄土地层灌浆试验施工技术与成果分析

湿陷性黄土的固结灌浆施工在国内外均无成功的先例，通过本次试验，为隧洞围岩黄土地层灌浆施工探索了一套较为成功的施工工艺和灌浆参数。针对不同材料的可灌性进行了对比研究。