本文選題：混凝土空心橋墩　切入點(diǎn)：日照溫度場(chǎng)　出處：《重慶大學(xué)》2014年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：混凝土空心橋梁結(jié)構(gòu)如果裸露于大自然環(huán)境中，將會(huì)長(zhǎng)期經(jīng)受著各種復(fù)雜的環(huán)境條件變化的影響，從而使結(jié)構(gòu)產(chǎn)生隨時(shí)間變化的非線性溫度荷載并產(chǎn)生溫度效應(yīng)。這種非線性的溫度荷載在某些情況下產(chǎn)生的溫度效應(yīng)可能要比其他荷載產(chǎn)生的效應(yīng)還要大，非線性的溫度荷載使得混凝土空心橋梁結(jié)構(gòu)開(kāi)裂破損，從而嚴(yán)重影響結(jié)構(gòu)的使用安全。因此，要控制橋梁結(jié)構(gòu)的安全，研究分析混凝土空心橋梁結(jié)構(gòu)的溫度荷載及效應(yīng)是十分必要的。 本論文主要以“山區(qū)高速鐵路橋梁混凝土高墩結(jié)構(gòu)設(shè)計(jì)技術(shù)研究”重點(diǎn)科研項(xiàng)目為依托，以建設(shè)中的貴廣線幸福源水庫(kù)特大橋?yàn)楣こ瘫尘埃x取了該橋的12#橋墩為研究對(duì)象，針對(duì)混凝土空心箱型截面橋墩的日照和寒潮溫度場(chǎng)與溫度效應(yīng)進(jìn)行了系統(tǒng)的分析研究。主要研究工作和結(jié)論如下： 本論文主要采用現(xiàn)場(chǎng)實(shí)測(cè)、數(shù)值模擬、數(shù)值計(jì)算和理論分析相結(jié)合的研究方法。通過(guò)回歸分析現(xiàn)場(chǎng)實(shí)測(cè)數(shù)據(jù)擬合提出適合廣西桂林片區(qū)的空心橋墩日照和寒潮溫度梯度模式；采用大型有限元軟件ANSYS建立橋墩有限元模型，數(shù)值模擬計(jì)算空心橋墩溫度場(chǎng)；對(duì)比分析現(xiàn)場(chǎng)實(shí)測(cè)數(shù)據(jù)與模擬數(shù)據(jù)，調(diào)整計(jì)算參數(shù)，通過(guò)模擬的數(shù)值計(jì)算橋墩的溫度效應(yīng)。 通過(guò)實(shí)測(cè)分析溫度場(chǎng)沿橋墩墩高方向的變化是均勻的，所以可以把三維溫度場(chǎng)當(dāng)成二維平面溫度場(chǎng)來(lái)計(jì)算；對(duì)幸福源水庫(kù)大橋12#橋墩的日照和寒潮溫度場(chǎng)進(jìn)行了不間斷觀測(cè)，運(yùn)用最小二乘法擬合提出了適合廣西桂林片區(qū)混凝土鐵路橋墩的日照和寒潮溫度梯度模式；采用ANSYS軟件按第三類(lèi)邊界條件來(lái)模擬計(jì)算混凝土箱型截面橋墩日照溫度場(chǎng)和溫度效應(yīng)是準(zhǔn)確可靠的，最大壓應(yīng)力達(dá)到5.99MPa，最大拉應(yīng)力達(dá)到2.24MPa，，墩頂最大位移達(dá)到6.081mm；采用ANSYS軟件按第一類(lèi)邊界條件來(lái)模擬計(jì)算混凝土箱型截面橋墩寒潮溫度場(chǎng)是準(zhǔn)確可靠的，最大拉應(yīng)力為4.66MPa，已經(jīng)超過(guò)了C40級(jí)混凝土的抗拉強(qiáng)度；通過(guò)對(duì)不同寒潮降溫值下橋墩寒潮溫度效應(yīng)的有限元分析可知,當(dāng)寒潮降溫使得橋墩內(nèi)外壁溫差為5℃時(shí)，橋墩外壁拉應(yīng)力相應(yīng)增大2.0MPa左右；內(nèi)壁壓應(yīng)力在順橋向方向增幅為1.1M Pa/5℃;內(nèi)壁壓應(yīng)力在橫橋向方向增幅為0.3MPa/5℃。
[Abstract]:If the concrete hollow bridge structure is exposed to the natural environment, it will endure the influence of various complex environmental conditions for a long time. So that the structure produces a nonlinear temperature load over time and a temperature effect, which, in some cases, may have a greater temperature effect than others. Nonlinear temperature load makes the concrete hollow bridge structure crack and damage, which seriously affects the safety of the use of the structure. Therefore, it is necessary to control the safety of the bridge structure. It is necessary to study and analyze the temperature load and effect of concrete hollow bridge structure. In this paper, based on the key scientific research project of "study on the structural Design of concrete High Pier structure of High-speed Railway Bridge in mountainous area", taking the large bridge of Xinyuan Reservoir in Guiguang Line as the engineering background, the 12# pier of the bridge is chosen as the research object. The temperature field and temperature effect of sunshine and cold wave of concrete hollow box section pier are studied systematically. The main work and conclusions are as follows:. This paper mainly adopts the research methods of field measurement, numerical simulation, numerical calculation and theoretical analysis. Through regression analysis, the paper puts forward the sunshine model of hollow bridge pier and the cold wave temperature gradient model suitable for Guangxi Guilin region. The finite element model of bridge pier is established by using the large-scale finite element software ANSYS, and the temperature field of hollow pier is numerically simulated, and the field measured data and simulation data are compared and analyzed, and the calculated parameters are adjusted, and the temperature effect of the pier is calculated by numerical simulation. The variation of temperature field along the high direction of pier is uniform, so the three-dimensional temperature field can be calculated as two-dimensional plane temperature field, and the sunshine and cold wave temperature field of 12# bridge pier of Xingyuan Reservoir Bridge are observed continuously. Using least square fitting, the sunshine and cold wave temperature gradient model of concrete bridge piers in Guilin region of Guangxi are put forward. It is accurate and reliable to simulate and calculate the sunshine temperature field and temperature effect of concrete box section pier by using ANSYS software according to the third kind of boundary condition. The maximum compressive stress is 5.99 MPA, the maximum tensile stress is 2.24 MPA, the maximum displacement of the pier top is 6.081mm. It is accurate and reliable to use ANSYS software to simulate and calculate the cold wave temperature field of concrete box section bridge pier according to the first type boundary condition. The maximum tensile stress is 4.66 MPA, which has exceeded the tensile strength of C40 grade concrete. Through the finite element analysis of the cold wave temperature effect of bridge pier under different cold wave cooling values, it can be seen that when the cold wave cooling makes the temperature difference between the inner and outer wall of the bridge pier to be 5 鈩

本文編號(hào)：1612146