高压旋喷桩处理软弱地基的研究

高压旋喷桩处理软弱地基包括复合地基承载力设计和高压旋喷桩施工方法.从高压旋喷桩的加固机理和计算参数的设计以及高压旋喷桩的施工工艺等方面,论述了高压旋喷桩处理软弱地基的技术可行性和适用性.     

单管法高压旋喷桩在地基加固中的应用

通过具体工程实例,探讨了单管法高压旋喷桩在地基加固中的应用,对地基加固方案进行了介绍,阐述了单管法高压旋喷桩的施工工艺和施工过程,工程实践证明,单管法高压旋喷桩工艺用于加固地基、防止基础沉降是可行的。     

高压旋喷桩加固技术在工程中的应用

对高压旋喷桩复合地基加固技术进行了研究,并以工程实例为背景,对高压旋喷桩复合地基加固技术的施工流程、加固原理进行了论述,按规范给出的方法,计算出了加固后的复合地基承载力,验证了采用高压旋喷桩加固技术的有效性。     

旋喷桩土木工程地基检测理论的研究及应用

旋喷桩在软土地基加固、桩基础施工、防砂土液化等方面应用较为广泛,特别是地基加固区域的工作面比较狭窄时,表现出了巨大的施工优越性。与其他地基加固方法不同的是,旋喷桩地基加固是在地层下一定深度范围内直接搅拌成桩的隐蔽工程,所以,不可能直观的检查到旋喷桩的成桩质量,只有通过切合实际的检测方式才能科学有效的检验地基加固的质量。论文主要通过对旋喷桩土木工程的地基检测理论及其应用进行研究,希望给相关的建筑企业提供一定的参考。     

高压旋喷桩在软土地基加固工程中的应用

广东省某市区开发项目工程建设中,有一座现状箱涵发生不均匀沉降。经过多个处理方案比选,应用高压旋喷桩对其软弱地基进行加固,并取得良好效果。本文通过此工程实例,介绍高压旋喷桩在对现有建筑地基加固时的施工工艺和质量控制要点,并说明高压旋喷桩作为软弱地基加固方法的特点和作用。     

高压旋喷扩底桩的设计与现场检测

针对某堆煤场区软弱地基,选择采用高压旋喷桩+高压旋喷扩底桩进行处理.首先,经过详细的设计计算,得出了具体的处理方案.然后结合室内试验、十字板剪切试验、静力触探试验和载荷板试验,对高压旋喷扩底桩的加固效果进行了分析.为与高压旋喷桩进行比较,还进行了深层土体竖向位移试验和土体水平位移试验等.检测结果表明,高压旋喷扩底桩对地基土加固效果显著,特别是对扩底处的持力层;较之高压旋喷桩,高压旋喷扩底桩可在一定程度上提高承载力.     

高压旋喷桩在加固既有建筑物地基中的设计应用

高压旋喷桩加固地基是地基处理的一种有效方法。以某2层办公危房地基加固为研究对象,对几种地基加固方案进行了分析对比,详细论述了采用高压旋喷桩加固既有建筑物的设计要点。通过该工程的成功实施,论述了高压旋喷桩加固既有建筑的优点及其施工注意事项,为同类工程的设计与工程应用提供有意义的参考经验。     

高压旋喷桩在海南滨海地区软基加固中的应用

通过对高压旋喷桩加固软土地基原理的阐述,分析了高压旋喷桩加固软土地基后对地基承载力的影响,并结合海南东环铁路桥涵软基处理实例,介绍了高压旋喷桩的布桩原则、施工工艺及施工质量控制等方面的一些做法,并对试验结果进行了分析,以推广旋喷桩在滨海地区软弱地基中的广泛应用。     

高压旋喷桩在既有建筑地基加固中的应用

高压旋喷桩是地基处理的有效方法之一,但是针对其在既有建筑地基加固工程上应用的研究相对较少。以一个工程实例作为研究对象,对高压旋喷桩加固的可行性进行了探索研究。通过对高压旋喷桩加固原理、应用优势、施工工艺优缺点比较分析,深入研究其在地基加固中的应用,探求简单易行的计算与设计方法,付诸工程实践并通过沉降监测进行效果验证。研究表明,在既有建筑地基加固实践中,高压旋喷桩对原建筑破坏小,加固效果显著,控制沉降明显,是一项行之有效的加固技术。     

岩溶场地油罐基础的纠偏加固

结合工程实例,分析了岩溶地基旋喷桩配合高压注浆的加固机理,并检测了其效果,表明旋喷桩配合高压注浆加固效果良好,是值得推广的岩溶地区地基加固方法。     

软土地基加固方案的确定

介绍了软土地基加固方案确定的基本过程。针对道路工程中出现的软土地基的加固问题,结合2个不同特点的工程实例,对加固方案的拟订、方案比较和确定进行了研究。实践证明,不同地区、不同情况的软土地基应采用不同的加固方案。     

Chemical injection to prevent building damage induced by ground water drainage from shallow tunnels

Progressive developments in the application of chemical injection have been acquired through out the centuries, starting from the ancient Romans. The method of silica based injection has been employed for a long time and has replaced the polyurethane injection method since the 1970s as a remedy in difficult ground conditions including fractured rock. Currently, various applications of chemical injections are available in civil and mining engineering, including ground stabilization, support anchoring, strata sealing, reduction and diversion of ground water flow and water ingress and creation of a load-bearing ring in tunneling. Drainage of the ground water in the overburden during tunneling will result in an increase in ground settlement by the evacuation of water and closure of the pores in overburden. In this research, the ground water level was decreased to 3 m from the original level and the ground settlement was recorded to reach 25 mm, while the inner tunnel vertical convergence was 6.5 mm after the drainage of 3.5 l/s ground water from the tunnel. Subsequent field measurements and observations indicated that the ground water drainage in the tunnel was reduced to 0–0.5 l/s and the surface settlements were stopped after the chemical injection.     

Chemical injection application at tunnel service shaft to prevent ground settlement induced by groundwater drainage: A case study

Chemical injections are used in a variety of applications in civil and mining engineering, including ground stabilization, support anchoring, strata sealing, reduction and diversion of groundwater flow and water ingress, and creation of a load-bearing ring during tunneling. Historically, injection application without pressure was first employed by the Romans. Polyurethane injections have been used in coal mines to stabilize roofs and to reduce problems regarding water ingress in shafts and tunnels. This paper focuses on chemical injection, which was employed to prevent ground settlement induced by groundwater drainage from the shaft. As a result of the drainage of 4.5 l/s groundwater from the Shaft 4, which was sunk for service at Guzelyali station of Izmir Metro Project, the groundwater level dropped 4 m from the original level, and ground settlement reached 98 mm, while the inner tunnel vertical convergence was 23 mm. This can be explained with the closure of pore volumes in the overburden. Ground settlement was stopped and groundwater level approached its original level after chemical injection.     

地基处理技术发展综述

国内外特别是我国近几年来地基处理的发展过程中,体现出将各种地基处理技术进行交叉、综合应用,形成了有特色的复合加固技术。本文对我国正在进行修订和编制的地基处理方面相关规范进行介绍,并对我国地基处理具有特色和代表性的发展进行回顾和总结。     

Effect of temperature on lime-soil stabilization

In earthworks, such as in the construction of a highway, it is prohibitively expensive to remove large volumes of unsatisfactory soils and replace them with more suitable material, particularly if it is to be imported. Therefore, much emphasis has been placed upon finding methods of modifying the properties of soils available at the site. This process is generally referred to as soil stabilization, and in its widest meaning comprises every physical, physico-chemical, and chemical method employed to enable a soil to serve better its intended engineering purpose. In its specific meaning in highway engineering, soil stabilization is the process by which soil is improved in order to use it as base, sub-base, and occasionally surface courses. Lime stabilization is one of the many processes available.     

某住宅楼倾斜原因与纠偏加固处理

导致该楼发生倾斜的主要原因有:南北两侧地基土工程性质差别较大,基础施工质量较差。据此提出对沉降多的地方限沉加固,对沉降少的区域采用深部应力释放和加载促沉,当建筑物沉降差异调至符合规范要求时,再进行地基整体加固,稳定沉降的思路。施工分限沉、加载锚桩施工和射水掏土应力释放、纠偏(促沉)、纠偏微调、加固、稳定六个阶段。实践证明,该住宅楼的纠偏加固处理是十分有效的。     

某地源热泵项目设计优化与全年运行效果实测分析

为实现地源热泵技术应用的突破,在保证室内舒适效果的前提下,提高系统效率降低系统能耗.通过选取5栋别墅样板间,进行地源热泵系统应用全过程跟踪.设计过程借助了全年负荷模拟工具校核设备选型与地下热平衡.施工时定期巡视以实现质量把控.项目建设了地温监测与能耗监测系统,监测全年冷热负荷对土壤温度波动的影响,对运行能耗和室内温湿度数据进行分析,提取影响运行效果的关键因素,为技术应用推广积累了大量的基础数据.     

化学生物絮凝工艺处理低浓城市污水研究

考察了化学生物絮凝和化学混凝两工艺对低浓度城市污水的处理效果。试验表明，在PAC加入量为70mg／L、PAM加入量为0．5mg／L、絮凝反应时间为35min时，化学生物絮凝工艺对COD的平均去除率为61％，对TP的平均去除率为70％，对SS的平均去除率为90％，效果明显优于化学混凝工艺；在化学生物絮凝工艺中污泥回流不仅可以提高去除效果，而且对进水水质波动有一定的稳定作用。     

加强建筑地基与基础工程质量安全性的若干建议

文中指出建筑工程的基础设计、施工与建筑场地条件密切相关;确保建筑地基与基础的安全、牢靠,除了认真执行工程技术标准,更重要的还与设计、施工人员的质量意识、责任心和工作经验有关,同时还应不断创新质量安全管理机制。     

复合地基桩型的合理选择

不同桩型复合地基各有特点，都有一定的适用范围。对于同一软土地基进行处理，选用不同桩型的复合地基，加固效果及经济效益可能差别很大。本文简要分析了不同桩型复合地基的加固机理，复合地基性状，简述了复合地基中桩型的选择原则，并根据不同地质条件，不同使用要求，对桩型的选择情况进行了归纳。