【摘要】：高壩混凝土澆筑用量大、施工強度島、施工條件復(fù)雜,既要考慮導(dǎo)流、防洪渡汛、、施工環(huán)境等備個要素影響,又要考慮溫度控制、結(jié)構(gòu)應(yīng)力等因素的影響,所以大型混凝土壩施工是一個非常重要而又復(fù)雜的過程。與此同時,為謀求提早蓄水發(fā)電效益,在實際水利工程施工中,混凝土施工中容易開裂,影響工程的安全,所以有必要分析影響混凝土施工中澆筑厚度和間歇期的因素,找到混凝土的快速澆筑的規(guī)律,為以后類似工程的溫控設(shè)計提供借鑒和參考依據(jù)。本文建立了溢流壩三維有限元模型,研究了壩體在不同間歇時間、不同澆筑厚度條件下碾壓混凝土壩的溫度和應(yīng)力的變化規(guī)律,研究結(jié)果表明:(1澆筑層厚越厚, 早期壩體內(nèi)部最高溫度越高。壩體不同區(qū)域最高溫度不僅與澆筑厚度有關(guān),也與澆筑季節(jié)密切相關(guān),在低溫季節(jié)澆筑的混凝土,澆筑層越厚,最高溫度也越大�；炷粱A(chǔ)墊層區(qū)X、Y、Z方向拉應(yīng)力隨著澆筑厚度的增大而增大,三級配碾壓混凝土區(qū)X、Y、Z方向拉應(yīng)力隨著澆筑厚度的增大增大,二級配碾壓混凝土防滲層區(qū)X、Y,Z方向拉應(yīng)力隨著澆筑厚度的增大而減小,二級配常態(tài)混凝土 X、Y、Z方向拉應(yīng)力隨著澆筑厚度的增大而增大。(2) 當澆筑層厚不變時,隨著間歇期越長,散熱越充分,混凝土內(nèi)部最高溫度越低,壩體混凝土內(nèi)外溫差也就越小�；炷粱A(chǔ)墊層區(qū)間歇時間越長,X、Y、Z方向拉應(yīng)力越大,壩踵部位處于應(yīng)力集中狀態(tài):三級配配碾壓混凝土區(qū)X、Y、Z方向拉應(yīng)力隨著間歇時間的增大而減小:二級配上游防滲層碾壓混凝土區(qū)X、Y、Z方向拉應(yīng)力隨著間歇時間的增大而增大;二級配態(tài)溢流面混凝土X、Y、Z方向拉應(yīng)力隨著間歇時間的增大而減小。(3)最后以某工程為例,擬定了 7個方案進行快速施工溫控研究,由計算結(jié)果可知:方案2、方案3、方案6和方案7能滿足溫度場和溫度應(yīng)力要求。但在采取相同的溫控措施條件下,方案6的施工工期最短,大大加快了施工進度,這樣既節(jié)省工程投資還能使工程提前發(fā)揮效益,因此,采納方案6作為快速溫控方案更為合理。
[Abstract]:The high dam concrete has the advantages of large amount of concrete pouring, construction intensity island and complex construction conditions. It is not only necessary to consider the influence of factors such as diversion, flood control, construction environment and so on, but also the influence of temperature control, structural stress and other factors. So the construction of large concrete dam is a very important and complex process. At the same time, in order to advance the benefit of water storage and power generation, in the actual water conservancy construction, the concrete is prone to crack, which affects the safety of the project, so it is necessary to analyze the factors that affect the pouring thickness and the interval period in the concrete construction. The rule of rapid pouring of concrete is found, which provides reference and reference for the temperature control design of similar projects in the future. In this paper, a three-dimensional finite element model of overflow dam is established, and the variation of temperature and stress of RCC dam under different intermittent time and different pouring thickness is studied. The results show that: (1) the thickness of pouring layer is thicker, The highest temperature in the early dam body is higher. The highest temperature in different regions of the dam is not only related to the pouring thickness but also to the pouring season. The thicker the pouring layer is, the higher the maximum temperature is during the low temperature season. The tensile stress in the direction of XFY _ (Z) direction increases with the increase of pouring thickness in the cushion area of concrete foundation, and the tensile stress in the direction of X _ (Y) _ (Z) direction increases with the increase of the thickness of pouring in the area of tertiary RCC, and in the zone of impermeable layer of secondary RCC, the tensile stress increases with the increase of pouring thickness. The tensile stress in YZ direction decreases with the increase of pouring thickness, and the tensile stress increases with the increase of pouring thickness in secondary normal concrete. (2) when the thickness of pouring layer is constant, with the increase of intermission time, The more sufficient the heat dissipation, the lower the maximum temperature of concrete and the smaller the temperature difference between inside and outside of dam. The longer the interval time in the cushion area of concrete foundation is, the greater the tensile stress is in the direction of XY, and the stress concentration in the dam heel is in the state of stress concentration. The tensile stress in Z direction decreases with the increase of intermittent time. The tensile stress in the direction of XY _ (Z) direction decreases with the increase of intermittent time. (3) finally, taking a project as an example, 7 schemes are worked out to study the temperature control of rapid construction. The calculation results show that: scheme 2, Schemes 3, 6 and 7 can meet the temperature field and stress requirements. However, under the same temperature control measures, the construction period of project 6 is the shortest, which greatly accelerates the construction progress, which not only saves the project investment but also makes the project benefit in advance. It is more reasonable to adopt scheme 6 as a fast temperature control scheme.
【學位授予單位】：西安理工大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TV544

【參考文獻】

相關(guān)期刊論文 前10條

1 劉健;董福品;;混凝土性能參數(shù)對壩體溫度應(yīng)力影響的敏感性分析[J];水力發(fā)電;2015年06期

2 王海波;強晟;王仁坤;;快速澆筑條件下混凝土壩施工期溫度與應(yīng)力特性和防裂方法[J];應(yīng)用基礎(chǔ)與工程科學學報;2015年02期

3 謝微;董福品;劉虎虎;;混凝土澆筑坯層對壩體溫度應(yīng)力場的影響[J];人民長江;2012年21期

4 張彬;李文;馬福軍;;錦屏一級水電站高拱壩混凝土快速施工技術(shù)[J];四川水力發(fā)電;2011年01期

5 ;Theory on real-time control of construction quality and progress and its application to high arc dam[J];Science China(Technological Sciences);2010年10期

6 強晟;朱岳明;鐘谷良;練松濤;苗孝哲;;混凝土壩厚層短歇的快速澆筑方法及應(yīng)用[J];三峽大學學報(自然科學版);2010年04期

7 朱伯芳;;論混凝土壩的水管冷卻[J];水利學報;2010年05期

8 韓炳蘭;商永紅;樂運紅;;向家壩水電站左岸大壩混凝土快速施工[J];水力發(fā)電;2010年02期

9 劉林生;;錦屏一級水電站大壩混凝土溫控研究[J];人民長江;2009年18期

10 張楊;強晟;邵戰(zhàn)濤;;水管冷卻混凝土溫度場離散算法網(wǎng)格密度研究[J];三峽大學學報(自然科學版);2009年03期

相關(guān)博士學位論文 前1條

1 張曉飛;大體積混凝土結(jié)構(gòu)溫度場和應(yīng)力場仿真計算研究[D];西安理工大學;2009年

，

本文編號：2333729