浅谈地下工程灌浆堵漏

通过对灌浆堵漏的概述,从灌浆材料、灌浆工艺、灌浆参数等方面进行了具体归纳总结,从而提高灌浆堵漏效率,以达到防渗堵漏,确保建筑结构防水工程施工质量的目的。     

化学灌浆技术的发展与展望

从灌浆材料、灌浆方法、灌浆工艺、灌浆设备、灌浆施工监控、灌浆效果检测、灌浆理论及灌浆技术的应用规模等几个方面对化学灌浆技术的发展进行综述。同时,展望未来化学灌浆技术的发展,为化学灌浆技术的研究及其工程应用指出一条捷径。     

低压灌浆法解决渗水问题

简要地介绍了如何应用低压灌浆法解决建筑物的渗漏问题。引入低压灌浆法处理渗漏,改变了以往渗漏处理施工中工程量大、效果不稳定等缺点。通过掺入部分添加剂来降低成本,引入监测系统用来收集和处理诸如灌浆压力、浆液稠度和耗浆量等重要参数,这不仅使工作效率大大提高,而且减小了灌浆对原有结构的破坏性,还能更好地控制灌浆工序和了解灌浆过程本身。     

压密灌浆在素填土地基中的应用与研究

结合工程概况及其工程地质条件,提出采用压密灌浆加固、控制灌浆量和灌浆压力、采用二次灌浆和补充灌浆法等施工措施,通过现场检测,收到了良好的灌浆效果,以推广压密灌浆在素填土地基处理中的广泛应用。     

化学灌浆在不良地基处理中的应用现状及其进展

结合现阶段化学灌浆技术的发展情况,在分析以往工程实例的基础上,简要论述了劈裂灌浆、压密灌浆及渗透灌浆技术在不良地基处理中的应用和发展情况。根据这些方法的不同特点和在不同地基处理中的应用效果,总结和归纳了各自的应用范围和优缺点,并对今后的研究方向和发展前景进行了探讨。最后,分析了化学灌浆技术在地基处理及其它工程方面的良好应用效果及发展前景。     

土石坝坝基帷幕灌浆设计探讨

以帷幕灌浆布置设计、灌浆材料、灌浆压力、灌浆方法、终孔及封堵方法等方面对帷幕灌浆的设计及施工进行了介绍,并对灌浆过程中出现异常情况的处理措施进行了阐述,最后对灌浆效果和灌浆质量进行了分析,以保证坝基灌浆优质经济。     

劈裂灌浆扩散机理研究

劈裂灌浆在实际工程中应用相当广泛。由于影响浆液扩散的因素众多,劈裂灌浆扩散机理尚不明确,尤其是不同给压方式(稳压和脉动)对浆液扩散的影响研究很少,对这两种方式下的劈裂灌浆机理进行了探讨。对于稳压灌浆方式,基于水力劈裂缝的扩展形态来考虑浆液的运动,视劈裂注浆扩散形态为平面辐射椭圆,采用恒缝高矩形断面模型,推导出宾汉流体的劈裂灌浆扩散方程,并分析了灌浆压力、浆材黏度、土体弹性模数、劈裂通道宽度对浆液扩散范围的影响。对于脉动灌浆方式,由于施加给受灌体荷载的延滞效应和脉动叠加作用,多次脉动灌入的浆液会使劈裂通道宽度逐渐增大,采用扁球体的劈裂灌浆模型,推导出脉动方式时的浆液扩散方程,分析了脉动灌浆频率等与浆液扩散距离的相互关系;结果表明,浆液的扩散距离与脉动频率的关系曲线存在一个极小值,发生在脉动频率为10 min次时,这一参数可作为脉动灌浆方式的控制参数。最后将前人的稳压灌浆模型与本文的脉动模型与相互比较,研究两种灌浆方式劈裂扩散机理的差异,得到脉动灌浆时浆液扩散距离要远短于稳压方式的,表明通过采用脉动灌浆,调节相关参数能有效控制浆材扩散范围,相关规律可为工程实际提供理论依据。     

水轮机蜗壳灌浆技术在西洱河水电站中的应用

水力发电工程中的灌浆技术主要有水泥灌浆与化学灌桨两种方法,水轮机蜗壳灌浆技术主要用于处理水轮机蜗壳的钢衬与混凝土结合部分的脱空问题。文章通过西洱河水电厂工程实例,重点阐述了水泥灌浆和化学灌浆两种方法在水轮机蜗壳脱空处理中的应用及效果。     

水利工程的灌浆施工技术

灌浆施工技术在水利建设中起着非常重要的作用,所以灌浆工序高效完成是确保水工建筑物的高质量的有效手段.因此,在水利工程建设中,首先要考虑灌浆过程,严格控制灌浆施工要点以及保证灌浆施工的质量.在分析了灌浆在水利工程中的应用基础上,总结了水利工程中常用的灌浆施工技术,以大坝基础灌浆为例,从大坝分类、大坝灌浆工艺流程及大坝基础...     

地下建筑结构中的膜体防渗灌浆

膜体防渗灌浆是通过在结构内侧的钻孔将灌浆材料压入结构外侧形成防渗膜体的方法。该方法利用了接触灌浆原理,可保证浆液在建筑结构与地基土接触层之间形成灌浆帷幕。膜体防渗灌浆设计包括灌浆孔位设计、灌浆孔深设计、灌浆材料和灌浆压力设计四部分内容。介绍了三类膜体防渗灌浆工程实例:地下室混凝土底板防水、泄洪隧洞混凝土衬砌防渗和人防通道砖墙防水。实践证明此施工技术具有较好的技术经济性能。     

高水压粉砂地层泥水盾构水下到达施工技术

结合武汉地铁二号线越江隧道工程水下到达的施工经验,介绍了如何创造条件实现泥水盾构水下到达,安全可靠地完成泥水盾构到达施工,重点论述了端头旋喷加固、冷冻加固以及基坑回填、盾构掘进等水下到达关键施工技术。该工程采用端头旋喷加固和冷冻加固技术相结合,洞门破除后实施基坑回填,成功地解决了盾构到达过程中高水压风险,可为类似工程提供一定的参考和借鉴。     

Filtration and penetrability of cement-based grout: Study performed with a short slot

Filtration of cement-based grout during penetration through fractures in rock is an important issue while sealing the rock around tunnels. Whether a type of grout could be designed to penetrate a fracture of a certain aperture without filtration is an interesting question that needs to be further investigated. This study examines the question of whether grout penetration can be measured using our designed measuring method as well as which factors and processes influence the penetrability and filtration of the grout.The penetration and filtration of grout are complex processes influenced by many factors such as the grain-size curve of the cement, hydration and flocculation, pressure, grain concentration, and the geometry of constriction.The measured results were in agreement with the predicted results, indicating that the filtration process in the given geometry describes correctly.     

长管棚注浆技术在半软半硬地质条件下的应用

以昆石高速公路小团山隧道下行线出口施工为例 ,介绍了在半软半硬地质条件下的长管棚施工方法、注意事项以及施工效果 ,保证了开挖后围岩的基本稳定     

Investigation and assessment of pre-grouted rock mass

Pre-grouting is a technique for reducing water ingress into tunnels and caverns by grouting fractures and joints prior to excavation. This study investigates pre-grouted rock mass to evaluate grout penetration in fractures and transmissivity of water in the rock mass surrounding the built tunnel, with the use for core drilling, OTV, high-precision water injection tests and core logging. The study was performed in three tunnel localities, in tunnels excavated in connection with the Follo Line project in Norway, where pre-grouting was performed using cement-based grouts. It was found less cement than expected in fractures with small apertures, compared with results of grout penetrability in laboratory studies of similar grouts. Further, it was found that fractures in coarse-grained rock types had rougher fracture surfaces and higher hydraulic apertures, than fractures in fine-grained rock types. It was also found that fractures with smoother surfaces had smaller hydraulic apertures in general. Hydraulic jacking was evidenced during the pre-grouting in this area, which is likely to have contributed to unnecessary high grout consumption.

     

Control of rock jacking considering spread of grout and grouting pressure

This paper describes a theoretical approach for monitoring fracture dilatancy (or “jacking”) during grouting. From this, a methodology to optimize the grout pumping pressure has been developed, based on the required penetration length (i.e. the distance that the grout spreads from the grout hole into the network of fractures within the rock mass). Empirical rules are put forward to prevent the damage that may result from uncontrolled deformation (Jacking) of the fractures, by limiting either pumping pressure or the injected grout volume, or by a combination of both. The state of the fractures and the spread of the grout when these limits are reached are discussed. The theoretical approach, which is referred to here as the Real Time Grouting Control Method, enables the estimation of grout penetration length or “spread” in real time. This gives an opportunity to monitor fracture dilation as it happens and, for the purpose of this paper, the allowable limits of elastic deformation and jacking have been estimated based on the grout spread. Two case histories are analyzed, for which the physical reaction of the fracture deformation with time and grout spread are determined from the recorded pressure and flow. By comparing the observed physical reaction with the theories for jacking presented here, the Real Time Grouting Control Method has been validated, and it is shown that this theoretical approach is superior to commonly used empirical methods, in that it allows the optimization of the pumping pressure to achieve a given penetration length in the shortest time and with an acceptable fracture dilatancy. This approach is a major step forward in customizing grouting works.     

基于牛顿流体的海底隧道穿越裂隙岩体注浆扩散半径计算

在分析胶州湾海底隧道注浆方案及浆液特性的基础上,采用牛顿流体类的刘嘉才公式进行裂隙岩体注浆扩散半径计算。计算结果表明:当设计注浆压力为3～4MPa、注浆孔半径为5cm和注浆时间为1800～3600s时,浆液的扩散半径能满足设计要求;浆液的扩散半径随着注浆时间的增加而增大,在注浆时间相同时,浆液的扩散半径随着裂隙宽度的减小而减小;浆液的扩散半径随着注浆压力的增加而增大,但在注浆压力相同时,浆液的扩散半径随着裂隙宽度的减小而减小。     

Single fluid jet-grout strength and deformation properties

The use of sub-horizontal jet-grout columns in the construction of soft ground tunnels is a popular method to provide excavation support. The sequential installation of jet-grout columns in a tunneling environment will result in the jet-grout columns being loaded in a staged manner, resulting in the jet-grout material properties and installation order affecting the magnitude and distribution of surface settlements and face deformations. A laboratory program was carried out to quantify the short-term (<24 h) development of strength and stiffness of a grout with a composition similar to that found in the construction of jet-grout columns. The laboratory tests were conducted at 8 °C to simulate the ground temperatures. Also the laboratory test cylinders were insulated to simulate the boundary condition differences between 600-mm-diameter jet-grout columns in soil and the 76-mm-diameter laboratory samples.     

花管注浆预加固对隧道稳定性的影响及方案优化

花管注浆常应用于山岭隧道浅埋偏压段开挖前的土体预加固,在前人研究成果的基础上,本文对隧道浅埋偏压段地表钢管预加固不同方案的力学效果进行较详细的研究,探讨其对隧道稳定性的影响,同时进行方案的优化。     

基坑开挖引起隧道水平变形的被动与注浆主动控制研究

对于邻近基坑的地铁结构保护问题,现有研究多集中于加强基坑自身支护体系、优化开挖方案等被动控制措施,此类方法缺乏在基坑开挖过程中对控制隧道变形的适时性和主动性,且会造成基坑造价提高、工期延长。以某邻近地铁结构的大面积基坑工程为例,分析了基坑施工中地铁结构的变形规律,进行了注浆对土体及隧道水平变形主动控制的试验及应用实践。在此基础上,通过数值模拟对几种隧道变形控制方法进行了对比和评价,并进行了注浆方案的优化研究。工程案例以及数值模拟结果均表明基坑分区分期开挖、分仓开挖、加强支护体系等被动控制措施具有较大局限性,而适时注浆主动控制隧道变形技术较为经济有效。在注浆策略上,多排孔注浆时"近距离、多孔位、小方量、由远及近"的注浆方案优于"远距离、少孔位、大方量、由近及远"的方案。主动注浆控制技术具有成本低、工期短、适时控制隧道变形等优点,条件适当时明显优于分区分期开挖等被动措施。     

SK高强无收缩灌浆料研制与应用

SK高强无收缩灌浆料可用于配制灌浆材料 (如灌制地脚螺栓、铆固等 ) ,结构自防水 ,自流平地面 ,屋面材料的施工及结构加固等 ;它施工快速、方便 ,价格低。高强无收缩灌浆料研制、性能分析以及应用