發(fā)布時間：2018-10-11 07:31

【摘要】：目前大體積混凝土已應(yīng)用于土木工程的各個領(lǐng)域中。但是,大體積混凝土在澆筑施工過程中,水泥會產(chǎn)生大量的水化熱,這樣混凝土內(nèi)部積聚熱量溫度高,產(chǎn)生壓應(yīng)力；外部由于空氣流通、散發(fā),溫度低,產(chǎn)生拉應(yīng)力；這樣很容易引起混凝土的張拉開裂。所以,對于大體積混凝土的施工,控制大體積混凝土的裂縫尤為關(guān)鍵。 我國規(guī)范對大體積混凝土的求解只給出了方便求解的經(jīng)驗公式,但是給出的經(jīng)驗公式忽略了溫度場連續(xù)變化以及外界溫度不斷變化的影響等其他影響因素。因此按照規(guī)范給出的方法計算出來的溫度以及應(yīng)力跟現(xiàn)場實際的情況相差很大。很多專家學(xué)者紛紛致力于大體積混凝土求解的研究中。 本文,從目前兩種最為廣泛的求解溫度場方法(即有限差分法和有限單元法)出發(fā),首先從建筑工程大體積混凝土出發(fā),結(jié)合具體某高層建筑的大體積混凝土筏板基礎(chǔ),對其進(jìn)行基于有限差分法的計算,并將計算結(jié)果與現(xiàn)場實測的結(jié)果進(jìn)行對比分析,結(jié)果表明有限差分法對溫度場計算方法可行。 然后,又從一個水利工程出發(fā),結(jié)合一個橋墩的大體積混凝土,采用ANSYS軟件對整個澆筑過程進(jìn)行有限單元法分析計算,為現(xiàn)場大體積施工提供了一定的指導(dǎo)作用。 最后,本文提出了大體積混凝土溫度控制的幾個具體技術(shù)措施,并對這些措施進(jìn)行了研究,旨在更加有效的降低大體積混凝土產(chǎn)生裂縫的可能性。因此,在大體積混凝土澆筑過程中,本文對大體積混凝土的水化熱分析計算及裂縫控制的研究具有重要意義。
[Abstract]:At present, mass concrete has been used in various fields of civil engineering. However, during the construction of mass concrete, the cement will produce a large amount of hydration heat, thus the internal heat accumulation temperature of the concrete will be high, and the compressive stress will be produced, while the external air circulation, the emission, the low temperature and the tensile stress will be produced. This will easily lead to tensile cracking of concrete. Therefore, for the construction of mass concrete, the crack control of mass concrete is particularly critical. The code of our country only gives the empirical formula for solving mass concrete conveniently, but the empirical formula neglects the continuous variation of temperature field and the influence of changing external temperature, etc. Therefore, the temperature and stress calculated according to the method given in the code are quite different from the actual situation in the field. Many experts and scholars have devoted themselves to the research of mass concrete solution. In this paper, starting from the two most widely used methods to solve the temperature field at present, namely, the finite difference method and the finite element method, the mass concrete raft foundation of a concrete high-rise building is combined with the mass concrete in building engineering. The finite difference method is used to calculate the temperature field, and the results are compared with the measured results. The results show that the finite difference method is feasible for the temperature field calculation. Then, starting from a water conservancy project and combining with the mass concrete of a bridge pier, the finite element method is used to analyze and calculate the whole pouring process by using ANSYS software, which provides some guidance for the field mass construction. Finally, several concrete technical measures for temperature control of mass concrete are put forward, and these measures are studied in order to reduce the possibility of cracks in mass concrete more effectively. Therefore, in the process of mass concrete pouring, this paper is of great significance to the study of hydration heat analysis and crack control of mass concrete.
【學(xué)位授予單位】：安徽理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TU755

【參考文獻(xiàn)】

相關(guān)期刊論文 前6條

1 徐俊;江昔平;孟令飛;盧昌龍;;揚州商業(yè)廣場筏板基礎(chǔ)的溫控措施[J];工業(yè)建筑;2013年11期

2 劉寧,柯慶清,閻旭;重力壩的隨機溫度場初探[J];河海大學(xué)學(xué)報(自然科學(xué)版);2000年03期

3 楊華全,覃理利,董維佳;摻粉煤灰和高效減水劑對水泥水化熱的影響[J];混凝土;2001年12期

4 劉寧,劉光廷;大體積混凝土結(jié)構(gòu)隨機溫度徐變應(yīng)力計算方法研究[J];力學(xué)學(xué)報;1997年02期

5 朱伯芳;混凝土的彈性模量、徐變度與應(yīng)力松弛系數(shù)[J];水利學(xué)報;1985年09期

6 楊碧華,李惠強;早齡期大體積混凝土溫度應(yīng)力與裂縫的關(guān)系[J];華中科技大學(xué)學(xué)報(城市科學(xué)版);2002年04期

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本文編號：2263362