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软土地基处理方法的选择,都是对地基的性状、防洪堤与道路的等级、施工条件、施工期限以及周围环境的影响等各种条件,进行综合分析比较来选择经济合理的处理方法。因此,所选择的处理方法往往都是对多种处理方法的综合运用。本文介绍几种常见软基处理方法,可供同行参考。 相似文献
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软土地基处理方法很多,且新的技术不断得到应用,但每种处理方法都有它的适用范围和局限性,所以软土地基处理的核心是处理方法的正确选择与实施.本文主要讲述市政道路工程中软土地基处理措施的原理以及施工中的质量控制方法,同时对渐趋成熟并已有广泛应用背景的处理技术作简要介绍. 相似文献
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软地基加固处理是为了在地基处理的设计和施工中贯彻执行国家的技术经济政策,做到安全适用、技术先进、经济合理、确保质量、保护环境。软地基加固处理方法有很多,换填土是最普遍也是最简单的。换填土就是把软弱土层挖方然后换成填好的土层。本文就软地基加固处理的常用方法,软地基加固处理前的准备工作以及施工中的注意事项和地基处理方法的步骤确定进行简单的叙述。 相似文献
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软弱地基的处理是工程施工中常遇到的问题,处理的方法也很多,但各种方法的处理费用、工期差别很大。本文介绍地基处理新技术——小口径桩复合地基的设计、施工方法,并通过工程实例总结出小口径桩复合地基的优点。籍此说明该方法用于处理软弱地基的实用价值。 相似文献
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废弃物老港处置场渗沥水处理技术 总被引:1,自引:0,他引:1
渗沥水是垃圾填埋处理中极易给环境带来二次污染的废水,因其产量和性质受各种因素的影响而复杂多变,较难处理。所以一般采取多种方法结合的工艺对其进行处理。一些经济发达的国家采用的处理方法更是五花八门,大都采用工厂化的设施处理,但要使出水达到排放要求,其费用是非常昂贵的。 相似文献
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《Planning》2014,(8)
水泥土置换原状土作为软土地基基础处理的一种方法,在水利工程特别是软土地基上的水利工程中应用较为广泛。一方面该方法施工成本低,可就地取材;另一方面,相对于其它地基处理方法来说,施工快捷,风险较小,可以缩短工期,是一种成本低,工期短的地基处理方法。 相似文献
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目前,道路软基处理方法较多,由于不同地区软土性质差别较大,因而处理方法也因地而异。软基处理的主要目的是控制工后沉降和保证路堤的稳定性。本文主要分析了目前市政道路软基处理现状,并结合工程实例,对软基处理方法及方案设计进行了探究。 相似文献
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Electrolysis of solutions containing certain electrolytes, through the use of novel electrodes, produces significant levels of ozone, oxygen, and chlorine at the anode. The process works at ordinary temperatures, and with dilute solutions. These solutions, after electrolysis, can be much more effective, by a factor of several hundred, against microorganisms than solutions containing comparable hypochlorite solutions. 相似文献
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This paper is concerned with the elastic flexural buckling of doubly symmetric columns with oblique restraints under concentric loading. Oblique restraints cause coupling between the principal axis deflections and rotations, and the flexural buckling mode involves simultaneous bending about both principal axes.The paper discusses the nature of oblique restraints, and presents exact and approximate solutions for the buckling loads of columns with rigid or elastic restraints against rotations at the ends. The exact solutions are obtained by solving the governing differential equations and boundary conditions, while the approximate solutions are based on energy solutions with assumed buckling displacements. The approximate solutions are sufficiently simple that they can be used in design, and are shown to be within 1% of the exact solutions. 相似文献
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四种不同形式的弹性悬索静力解答 总被引:10,自引:0,他引:10
首先回顾了悬索静力分析的研究历史,收集整理了国际上常用的不同坐标系下的两种解答及国内近年来推导的不同坐标系下的两种解答,通过同种坐标下国内、外解答的一致性和不同坐标系下国际上流行的两种解答一致性的证明,表明该四种解答是一致的,建议使用竖坐标轴正方向向上的解答,用国际上的相应解答建立悬索分析的有限元方法,用本文作者推导的解答进行索的设计与计算。 相似文献
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The process of wet oxidation breaks down organic substances in aqueous solution at elevated temperatures and pressures. Experimental wet oxidations were carried out on pure solutions of phenol, 2-chlorophenol and 4-nitrophenol. After 1-h wet oxidation, final concentrations of these compounds averaged 3% of their concentrations in the starting solutions. The toxicities of the starting compounds and the residual toxicity of the end-product solutions were measured with 48-h acute toxicity tests using Daphnia magna. The solutions of end products were all less toxic than the starting solutions by factors ranging from 10 to 120. However, the end-product solutions were somewhat more toxic than would be predicted from the known concentration of initial compound remaining in the solution of end products. 相似文献
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Detoxification of phenolic solutions with horseradish peroxidase and hydrogen peroxide 总被引:4,自引:0,他引:4
Phenolic solutions were treated with hydrogen peroxide and horseradish peroxidase (HRP) resulting in more than 95% removal of phenols within 3 h. Toxic compounds were formed during the treatment of aqueous solutions of phenol, 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol and 2-methylphenol. However, the toxicities of HRP-treated solutions decreased within 21 h after the completion of the enzymatic reaction, except in the case of 2-methylphenol. The process of detoxification was significantly accelerated upon the addition of hydrogen peroxide to the dephenolized solutions. Solutions that were treated in the presence of chitosan exhibited lower toxicities than solutions treated in its absence if they were allowed to incubate for an extended period of time. Treatment in the presence of polyethylene glycol resulted in significantly higher toxicities. The toxicity of treated solutions was dependent on the addition mode of HRP and hydrogen peroxide. Treated solutions were also completely detoxified following illumination with UV light. 相似文献
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针对适用于村镇地区的纤维增强工程塑料板橡胶隔震支座,提出基本力学性能的解析公式。基于隔震支座橡胶应力的静水压力假定,同时考虑了橡胶可压缩性及加劲层泊松比的影响,建立隔震支座单层分析单元在轴压及纯弯曲状态下的平衡方程,求得静水压力的解析解,进而通过积分求得单层分析单元的压缩模量及弯曲模量的解析解,并进行了参数分析。进一步推导出支座水平等效刚度的解析公式。基于abaqus软件建立一组支座单层分析单元的有限元模型,进行轴压和纯弯曲分析。将有限元结果与文献中两种解析公式以及本文中解析公式进行了对比。结果表明,推导的解析公式具有较高的精度,且较其他解析解具有明显的优势,为在村镇地区推广此类隔震支座提供理论分析基础。 相似文献
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This paper presents the exact and complete fundamental singular solutions for the boundary value problem of a n-layered elastic solid of either transverse isotropy or isotropy subject to body force vector at the interior of the solid. The layer number n is an arbitrary nonnegative integer. The mathematical theory of linear elasticity is one of the most classical field theories in mechanics and physics. It was developed and established by many well-known scientists and mathematicians over 200 years from 1638 to 1838. For more than 150 years from 1838 to present, one of the remaining key tasks in classical elasticity has been the mathematical derivation and formulation of exact solutions for various boundary value problems of interesting in science and engineering. However, exact solutions and/or fundamental singular solutions in closed form are still very limited in literature. The boundary-value problems of classical elasticity in n-layered and graded solids are also one of the classical problems challenging many researchers. Since 1984, the author has analytically and rigorously examined the solutions of such classical problems using the classical mathematical tools such as Fourier integral transforms. In particular, he has derived the exact and complete fundamental singular solutions for elasticity of either isotropic or transversely isotropic layered solids subject to concentrated loadings. The solutions in n-layered or graded solids can be calculated with any controlled accuracy in association with classical numerical integration techniques. Findings of this solution formulation are further used in the companion paper for mathematical verification of the solutions and further applications for exact and complete solutions of other problems in elasticity, elastodynamics, poroelasticty and thermoelasticity. The mathematical formulations and solutions have been named by other researchers as Yue’s approach, Yue’s treatment, Yue’s method and Yue’s solution. 相似文献
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It has recently been suggested that the future of the construction industry lies in adopting a new business model based on the concept of integrated solutions. Integrated solutions are combinations of products and services that address a customer's unique requirements throughout the life cycle, from development and design to systems integration, operations and decommissioning. Research on integrated solutions in other capital goods sectors has shown suppliers have had to create new business models, including developing new approaches to adding value, and building up new capabilities - especially in systems integration. The paper presents some preliminary empirical findings about construction industry perceptions of value, systems integration and integrated solutions that suggest the concept of built environment solutions provision is still at an early stage in its development and that the best opportunity for its introduction is in the context of private finance initiatives in the public sector or large clients who require repeatable solutions in the private sector. 相似文献
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通过分析封闭环境中群桩基础成桩后,桩间土体固结的边界条件和初始条件,建立了场地边界径向渗流受到阻隔时,饱和黏土中群桩桩间横观各向同性土体固结的定解条件,应用数学物理方法求得该问题的级数解答。解答可以计算和预测成桩后,桩间土体中任一位置任一时刻的超静孔隙水压力和固结度。当初始孔压为常数且假设桩间土体为各向同性时,级数解答可退化为太沙基单向固结问题的解答,验证了解答合理性。最后,通过实例分析,明确了桩间土体固结快慢的影响因数和规律。 相似文献
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为研究水岩化学作用对砂岩力学特性的影响,将桃源水电站的红砂岩加工成标准圆柱形试样,对其进行不同化学溶液作用下的腐蚀试验,获得红砂岩化学腐蚀过程中相对质量变化规律,同时测量记录各化学溶液pH值。利用岩石三轴测试系统对各种化学溶液浸泡后的红砂岩进行三轴压缩试验,探讨不同的化学溶液对红砂岩力学特性的腐蚀效应,获得水化学溶液对红砂岩强度和变形特性的影响规律。结果表明,试样质量的变化和化学溶液性质有关,试样相对质量变化存在明显差异。pH=13的化学溶液pH值随时间的增长有小幅度下降,其余化学溶液pH值随时间增长均趋于弱碱性(pH≈7.9)。根据溶液pH值的变化、试样相对质量的变化,分析化学溶液对岩石的腐蚀程度。三轴压缩试验结果表明,不同化学溶液对红砂岩力学性质的影响不同。离子成分及pH值均对红砂岩力学特性产生较大影响,各种化学溶液腐蚀后岩石的峰值强度、残余强度、弹性模量均有不同程度的下降。室内试验的结果可为构建红砂岩化学腐蚀条件下本构模型提供重要的试验资料。 相似文献