呼和浩特抽水蓄能电站蜗壳回填灌浆施工技术

针对呼和浩特抽水蓄能电站厂房座环、蜗壳阴角部位狭窄、空间小,混凝土浇筑易形成局部空腔的问题,介绍了环向充气式拔管、直埋式注浆钢管多循环平衡注浆技术,并介绍了施工的技术要求、施工程序和方法,提出了在灌浆过程中对蜗壳位移进行监测及应急处理措施。经质量检查,灌浆效果良好,解决了蜗壳座环底部回填灌浆难题。     

某高档别墅地下室渗漏治理与改进措施

通过对某别墅地下室渗漏水的治理过程,说明防水设计的重要性,特别阐述了应针对具体情况设计科学合理的防水构造的理念。     

The temperature ranges for maximum effectiveness of grain growth inhibitors in WC–Co alloys

In order to more effectively control the WC grain growth during liquid phase sintering of submicron WC–Co alloys, the temperature ranges where common grain growth inhibitors are most active have been determined. In the study, small additions (0.5% by weight) of TiC, TaC, NbC, VC, and Cr₃C₂ were added to WC–6Co and WC–10Co alloys. In some cases, a small amount of coarse WC powder was added to simulate the effect of discontinuous grain growth. The powder compacts were vacuum sintered at temperatures ranging from 1300 to 1575 °C. The magnetic coercivity and microstructure results indicated that VC is equally effective in limiting continuous grain growth for all temperatures within the temperature range while the other inhibitors become more effective with temperature. VC was also found to be the most effective inhibitor of discontinuous grain growth. The results of the investigation are expressed in terms of the effectiveness of grain growth inhibition as determined by microstructural analysis, magnetic coercivity and hardness.     

尾砂胶结充填新工艺在武山铜矿的研究与应用

为满足技改需求,扩大生产能力,武山铜矿的二期扩产设计采用下向分级尾砂胶结充填新工艺试验研究,通过研究改进胶结充填工艺过程、取消钢筋混凝土人工假底、扩大回采断面来扩大生产规模,提高工作效率。     

Influence of notch radius and R-curve behaviour on the fracture toughness evaluation of WC-Co cemented carbides

In this work the apparent fracture toughness of different grades of WC-Co cemented carbides has been evaluated by means of the single edge V-notched beam (SEVNB) method. The results are analysed, as a function of both the binder mean free path and the maximum steady-state crack shielding value, following a theoretical approach which assumes the existence of a small crack at the notch tip. The experimental findings indicate that larger defects at the notch tip and/or existence of R-curve behaviour imply higher (i.e. less restricted) values of the minimum notch radius required in SEVNB specimens for a reliable assessment of the fracture toughness of cemented carbides.     

高放废物地质处置库缓冲/回填材料的气体渗透问题研究进展

简要回顾和总结了国内外学者对处置库中的气体形成与渗透机制,注气试验装置与试验方法,以及气体渗透特性等方面的研究成果和最新进展。研究表明,深地质处置库运营过程中会由于金属无氧腐蚀等产生以氢气为主的多组分气体,气体在缓冲/回填材料中主要以对流–扩散渗流、黏性–毛细管两相流、局部膨胀通道渗流和沿宏观裂缝渗流等4种机制渗透。为此,各国学者先后研发了恒体积渗透装置、K0渗透装置、等向应力渗透装置和三轴渗透装置等注气试验装置,采用控制注气流量速率法或控制注气压力法开展了大量注气试验,发现缓冲/回填材料的气体渗透率和特征压力等渗透特性均与其物理性质和边界条件等诸多因素有关。考虑到处置库实际运营工况的复杂性,多场(热–水–化–力)多相(固–液–气)耦合条件下的缓冲/回填材料的气体渗透特性研究将是今后的一个重要工作方向。     

PCCP管施工回填土深层压实度检测方法研究

预应力钢筒混凝土管(简称PCCP)在国内外地下输水工程中得到广泛的应用,天津市南水北调配套工程亦使用了这种管材。回填土压实质量的好坏直接影响着工程质量,如何快速、准确地获得回填土深层压实度,对于保证工程质量十分重要。本文提出了轻型动力触探和无核密湿度仪相结合的回填土深层压实度检测方法,通过现场试验,获得轻型动力触探的锤击数与压实度并建立相关关系,并采用无核密湿度仪现场检测压实度以进行关系曲线的校准。通过实际工程应用,PCCP回填土深层压实度和轻型动力触探的锤击数具有良好的相关性,且该方法设备简单、操作容易、经济适用,并可随工程检验进行关系曲线的校验以提高精度,值得推广应用。     

Time- and temperature-dependence of compressive and tensile behaviors of polypropylene fiber-reinforced cemented paste backfill

The understanding of compressive and tensile behaviors of polypropylene fiber-reinforced cemented paste backfill (FR-CPB) play crucial roles in the successful implementation of reinforcement technique in underground mine backfilling operations. However, very limited studies have been performed to gain insight into the evolution of compressive and tensile behaviors and associated mechanical properties of FR-CPB under various curing temperatures from early to advanced ages. Thus, this study aims to investigate the time (7, 28, and 90 d)- and temperature (20°C, 35°C, and 45°C)-dependence of constitutive behavior and mechanical properties of FR-CPB. The obtained results show that pre- and post-failure behaviors of FR-CPB demonstrate strongly curing temperature-dependence from early to advanced ages. Moreover, the pseudo-hardening behavior is sensitive to curing temperature, especially at early ages. Furthermore, the mechanical properties including elastic modulus, material stiffness, strengths, brittleness, cohesion, and internal friction angle of FR-CPB show increasing trends with curing temperature as curing time elapses. Additionally, a predictive model is developed to capture the strong correlation between compressive and tensile strength of FR-CPB. The findings of this study will contribute to the successful implementation of FR-CPB technology.     

谈工程勘察钻孔回填的方式与方法

通过调查研究工程勘察过程中钻孔回填的情况,对现阶段大量钻孔未进行回填的原因作了分析,并论述了未回填钻孔对工程的危害,同时探索了钻孔回填所用材料、回填方法及要求,以供参考借鉴。     

超高水材料袋式长壁充填开采覆岩控制技术研究与应用

系统分析了超高水材料袋式充填开采采场覆岩结构的特点,得出了工作面支架需控岩层范围及其变化特征,揭示了长壁充填开采“支架-围岩”关系,明确了提高充填率是超高水材料袋式充填开采覆岩下沉控制的关键因素。结合亨健矿2515工作面充填开采地质与开采技术条件,开发并实施了隔板布置优化、采空区埋管补注浆充填、离层区打钻补注浆充填等充填率保障技术与工艺。现场实测结果表明,超高水材料袋式充填开采工作面矿压显现缓和、采场围岩破裂范围较小且能有效控制地表下沉：① 工作面巷道顶底板最大移近量为258 mm,两帮最大移近量为183 mm,围岩变形较小;② 微震监测系统表明,2515工作面超前破裂范围为20~30 m,围岩破裂高（深）度为顶板以上40 m至底板以下10 m,1个月后（推进距离60 m左右）已充填区域微震事件逐渐消失;③ 地表最大下沉量为265 mm,实测下沉系数为0.06。