地鐵車(chē)站側(cè)墻大體積混凝土施工養(yǎng)護(hù)測(cè)溫實(shí)驗(yàn)與數(shù)值模擬

摘"要"通過(guò)預(yù)埋溫度傳感器的方式，對(duì)深圳市某地鐵車(chē)站的兩面?zhèn)葔M(jìn)行溫度監(jiān)測(cè)，同時(shí)監(jiān)測(cè)環(huán)境溫度變化，分析地鐵車(chē)站側(cè)墻大體積混凝土結(jié)構(gòu)內(nèi)部由水化熱引起的溫度升降變化特征，進(jìn)一步分析混凝土內(nèi)部與表面、表面與環(huán)境、降溫速率等現(xiàn)象，得出混凝土溫度變化規(guī)律。利用ABAQUS有限元軟件對(duì)主要的溫度變化過(guò)程進(jìn)行數(shù)值模擬，建立側(cè)墻的三維應(yīng)力場(chǎng)-溫度場(chǎng)耦合模型，與試驗(yàn)數(shù)據(jù)對(duì)比驗(yàn)證其可靠性，對(duì)混凝土應(yīng)力狀態(tài)進(jìn)行分析，驗(yàn)證溫度應(yīng)力產(chǎn)生的原理，并且對(duì)地鐵側(cè)墻應(yīng)力易集中處做出預(yù)測(cè)，提出防止裂縫的相關(guān)措施。

關(guān)鍵詞"大體積混凝土，"溫度變化，"模型計(jì)算，"地鐵車(chē)站

Temperature Measurement Experiment and Numerical Simulation of Large-Volume Concretes During Their Construction and Maintenance on Side Walls of Subway Station

CHEN Hui^1，3"ZHANG Yingshuo^2，*"ZHANG Fengliang²"CHENG Chuo^1，3WANG Wenxu^1，3"ZHANG Xinqiang⁴

（1.China Construction First Bureau （Group）"Co.，"Ltd.，"Beijing 100071，"China；"2.School of Civil and Environmental Engineering Harbin Institute of Technology （Shenzhen），"Shenzhen 518055，"China；"3.China Construction First Bureau Group South China Construction Co.，"Ltd.，"Shenzhen 518000，"China；"4.China Construction Southern Investment Co.，"Ltd.，"Shenzhen 518000，"China）

Abstract"In this work the temperature of two side walls of a subway station under construction in Shenzhen was monitored，"and then the temperature fluctuation characteristics caused by the heat of hydration in the large-volume concrete structure of the side wall of the subway station were analyzed. Then the phenomenon of concrete interior and surface，"surface and environment，"cooling rate and other phenomena was further analyzed，"and the temperature change law of concrete was obtained. ABAQUS finite element software is used to simulate the whole temperature change process. A three-dimensional stress field-temperature field coupling model of the side wall was established，"and the result was compared with the experiment data to verify its reliability. The stress state of concrete was analyzed，"the principle of temperature stress was verified，"the stress concentration of the subway side wall was predicted，"and relevant measures to prevent cracks was proposed.

Keywords"large-volume concrete，"temperature changes，"model calculation，"metro stations

0"引"言

隨著城市人口的增多，城市面臨的地上交通壓力越來(lái)越大，地鐵這一地下交通方式的出現(xiàn)有效緩解了這種壓力。但是地鐵的修建成本昂貴，對(duì)工程技術(shù)的要求較高，并且大體積混凝土的裂縫問(wèn)題一直沒(méi)有得到很好的解決，導(dǎo)致后期的維護(hù)成本一直處于較高水平。

混凝土早期由于水化熱產(chǎn)生不均勻溫度場(chǎng)，導(dǎo)致混凝土不同區(qū)域產(chǎn)生不均勻變形，因?yàn)榛炷敛煌瑓^(qū)域之間的彼此約束和混凝土邊界約束，混凝土的變形不能自由釋放，由此產(chǎn)生的應(yīng)力叫作混凝土的早期溫度應(yīng)力。對(duì)于一個(gè)宏觀的混凝土構(gòu)件，其早期溫度應(yīng)力大體分為兩類(lèi)：內(nèi)部約束溫度應(yīng)力和外部約束溫度應(yīng)力。內(nèi)部約束溫度應(yīng)力是因?yàn)榛炷翜囟确植嫉牟痪鶆?、自身?nèi)外不同區(qū)域變形不協(xié)調(diào)導(dǎo)致的約束壓力；……