【摘 要】
：
The evaluation of alkali aggregate reaction in an existing subway tunnel is discussed in this paper.The petrographical examination of concrete thin sections was used to distinguish the alkali reactivi
【机 构】
：
Centeral Research Institute of Building and Construction, MCC Group ,No.88 Xitucheng Road Haidian Di
【出 处】
：
The 14th International Congress on the Chemistry of Cement (
论文部分内容阅读
The evaluation of alkali aggregate reaction in an existing subway tunnel is discussed in this paper.The petrographical examination of concrete thin sections was used to distinguish the alkali reactivity of the aggregates.Combined with alkali content analysis, it was deduced that part A of the tunnel had the potential for alkali-silica reaction.The typical form of alkali-silica gel was found in a broken surface of a concrete core,indicating the occurrence of ASR in this part of the subway tunnel.Some measures against ASR should be taken in order to continue use the existing subway.
其他文献
Returned concrete is the residual amount of fresh concrete that is not placed at the job site and returns to the ready-mix plant in the truck mixer.According to local conditions, returned concrete may
For the purpose to explore the durability of concrete structures in tropical marine environment, main destruction,carbonation depth, free chloride concentration (Cf) and total chloride concentration (
在离散元数值试验中,微观参数的取值直接决定着宏观参数.目前微观参数的研究多针对窄级配土、小尺寸的试样,基于宽级配粗粒土微观参数的研究较少.本文采用离散单元法,根据某水利工程宽级配粗粒料试验级配,采用常规大型三轴压缩试样尺寸,分析了线性接触模型中颗粒接触刚度和摩擦系数等微观参数对初始弹性模量、初始体积模量以及峰值强度的影响规律.研究发现:初始弹性模量和初始体积模量均随着刚度比的增大而减少,当刚度比较
海上风机受风、浪、流等多种随机荷载的作用,其结构状态关系到风电机组的安全和生产.本文拟采用静力分析方法结合风机结构模态分析,利用神经网络强大的映射功能进行风机结构状态监测研究.通过分析海上风机结构体系所受风、浪、流等环境荷载及其响应的特性，提出了海上风机结构状态监测的传感器布置原则，分析了神经网络应用于海上风机结构在线监测的可行性，讨论了输入输出量的获取方法，通过桶型基础过渡段的计算，神经网络具有
本文对平直型结构面锚固后的剪切破坏行为进行了室内模型试验,通过模型试验对不同锚固作用下的结构面剪切强度进行了研究,可知采用预应力锚索对结构面进行加固处理后,结构面抗剪强度和相应抗剪强度参数都有所提高.通过模型试验与理论分析,将加锚结构面中锚体随剪切位移增长所表现出来的阻滑抗剪作用大致分为预应力作用、销钉作用以及轴力增量阻滑三个方面.在推导的理论公式基础上,进行了室内平直结构面不同锚固条件下的模型试
During carbon sequestration, wellbore cement could be vulnerable to high pressure and temperature in underground storage settings.Deterioration has been observed under supercritical CO2 exposure condi
In the latest period hundreds of concrete viaducts were built in Poland within a short time range.Their characteristic feature was the use of high class concrete containing the CEM I 42,5 cement (stru
Fly ash air-entrained concrete specimens were tested in 3.5% NaCl solution with rapid freeze-thaw cycles.The relative dynamic modulus of elasticity and frost damaged layer thickness of concrete specim
This paper explores the effects of nano-kaolinite clay (NKC) on the behavior of concrete, when exposed to an acidic, chloride, and freeze-thaw environment.Ordinary Portland cement was partially substi
Decreasing of the durability of the concrete and reinforced concrete structures due to the alkali-silica reaction is actual problem worldwide.In 1968 at the first time it was reported about the destru