發(fā)布時(shí)間：2019-05-27 02:50

【摘要】：碾壓混凝土(RCC)重力壩施工工藝簡(jiǎn)單、造價(jià)較低、技術(shù)成熟，國(guó)內(nèi)外有無(wú)數(shù)的工程均采取了這種壩型。施工過(guò)程中溫度變化和徐變產(chǎn)生的應(yīng)力對(duì)壩體的影響較大，故對(duì)壩體溫度場(chǎng)、應(yīng)力場(chǎng)的分析十分必要。本文使用ANSYS有限元軟件中的參數(shù)化編程（簡(jiǎn)稱APDL），針對(duì)上存碾壓混凝土(RCC)重力壩工程，對(duì)其溫度場(chǎng)、徐變應(yīng)力場(chǎng)進(jìn)行分析，提出溫度控制措施。根據(jù)提供的勘查設(shè)計(jì)等資料，驗(yàn)證溫控措施的有效性，并得出指導(dǎo)工程實(shí)踐的措施。主要研究?jī)?nèi)容如下： （1）介紹RCC重力壩溫控研究思路，以及溫度場(chǎng)、徐變應(yīng)力場(chǎng)的計(jì)算原理，研究在仿真分析中如何實(shí)現(xiàn)徐變、邊界條件、本構(gòu)關(guān)系等的變化，根據(jù)實(shí)際工期安排、材料屬性、邊界條件及荷載等編寫(xiě)APDL，分析熱應(yīng)力耦合場(chǎng)，并通過(guò)生死單元技術(shù)模擬壩體澆筑過(guò)程。 （2）針對(duì)RCC重力壩中高溫期澆筑并埋設(shè)冷卻水管的部分，使用APDL編寫(xiě)優(yōu)化程序，得出最優(yōu)的通水參數(shù)，澆筑薄層在環(huán)境月平均氣溫超過(guò)20℃時(shí)，進(jìn)行通水冷卻，參考優(yōu)化通水參數(shù)并結(jié)合實(shí)際工程，選用通水流量15m3/d，水管間距0.75m*1.5m，通水溫差5℃，使得在滿足壩體溫度控制標(biāo)準(zhǔn)下更經(jīng)濟(jì)。當(dāng)溫度超過(guò)25℃進(jìn)入汛期，停止?jié)仓�。并提出智能冷卻水管模型，根據(jù)反饋動(dòng)態(tài)調(diào)節(jié)通水參數(shù)，保證大體積混凝土的強(qiáng)度、節(jié)約成本。 （3）對(duì)壩體溫度場(chǎng)及徐變應(yīng)力場(chǎng)進(jìn)行仿真分析，結(jié)果表明：無(wú)溫控措施下的典型壩段施工期最高溫度達(dá)到41℃，超過(guò)工程溫度控制標(biāo)準(zhǔn)，故采取高溫長(zhǎng)間歇和冷卻水管措施是必要的。采取相應(yīng)溫控措施后的典型溢流壩段溫度場(chǎng)云圖、典型溢流壩段等值線圖及典型節(jié)點(diǎn)溫度歷時(shí)曲線中最高溫度均控制在標(biāo)準(zhǔn)之內(nèi)。采取相應(yīng)溫控措施后的典型壩段徐變應(yīng)力場(chǎng)增量云圖、典型節(jié)點(diǎn)徐變應(yīng)力歷時(shí)曲線拉應(yīng)力均不超過(guò)0.2Mpa，不超過(guò)各級(jí)配材料的允許拉應(yīng)力。壩體整體的溫度場(chǎng)及徐變應(yīng)力場(chǎng)分布與工程一般規(guī)律基本一致，并為壩體施工提供了一系列溫控措施。
[Abstract]:Roller compacted concrete (RCC) gravity dam has the advantages of simple construction technology, low cost and mature technology. Many projects at home and abroad have adopted this kind of dam type. During the construction process, the stress produced by temperature change and creep has great influence on the dam body, so it is necessary to analyze the temperature field and stress field of the dam body. In this paper, the temperature field and creep stress field of RCC (RCC) gravity dam project are analyzed by using parametric programming in ANSYS finite element software (APDL), for short), and the temperature control measures are put forward. According to the survey and design data provided, the effectiveness of temperature control measures is verified, and the measures to guide the engineering practice are obtained. The main research contents are as follows: (1) this paper introduces the research idea of temperature control of RCC gravity dam, as well as the calculation principle of temperature field and creep stress field, and studies how to realize the change of creep, boundary condition and constitutive relation in simulation analysis. According to the actual construction period, material properties, boundary conditions and loads, APDL, analysis of thermal stress coupling field is compiled, and the pouring process of dam body is simulated by life and death element technique. (2) aiming at the part of the RCC gravity dam pouring and burying the cooling pipe during the high temperature period, the optimization program is compiled by APDL, and the optimal water flow parameters are obtained. When the monthly average temperature of the environment is more than 20 鈩，

本文編號(hào)：2485846