本文關(guān)鍵詞：采動區(qū)可續(xù)建箱型結(jié)構(gòu)承載特性研究　出處：《中國礦業(yè)大學(xué)》2015年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 采動區(qū) 箱型結(jié)構(gòu) 數(shù)值分析 承載特性 施工方法優(yōu)化

【摘要】：橋涵是連接交通的重要方式,箱型結(jié)構(gòu)作為抵抗變形的重要結(jié)構(gòu)形式,在采動區(qū)顯得尤為重要。雖然箱型結(jié)構(gòu)在采動區(qū)應(yīng)用較為廣泛,對箱型結(jié)構(gòu)承載能力和抗采動變形研究也較多,但是對箱型結(jié)構(gòu)可續(xù)建性研究較少,且多數(shù)都是過水箱涵的研究。本文以某礦北區(qū)鐵路專用線下4#箱型結(jié)構(gòu)為例,對箱型結(jié)構(gòu)的可續(xù)建性進(jìn)行研究。由于該箱型結(jié)構(gòu)續(xù)建完成以后總高度為11.6m,普通箱型結(jié)構(gòu)難以滿足承載要求,本文參考帶扶壁擋土墻設(shè)計,提出在結(jié)構(gòu)側(cè)墻外側(cè)設(shè)置扶壁的結(jié)構(gòu)形式。本文以無扶壁箱型結(jié)構(gòu)和帶扶壁箱型結(jié)構(gòu)兩種結(jié)構(gòu)形式為研究對象,運用軟件ANSYS分析箱型結(jié)構(gòu)在道砟厚度、傾斜影響下應(yīng)力變化規(guī)律。然后分析帶扶壁箱型結(jié)構(gòu)受續(xù)建因素影響下承載特性和合理的頂板結(jié)構(gòu)形式,并對箱型結(jié)構(gòu)施工方法進(jìn)行優(yōu)化。箱型結(jié)構(gòu)在采動影響下,隨著道砟厚度增加,兩種結(jié)構(gòu)形式的應(yīng)力最大值均呈現(xiàn)增大的趨勢。兩種結(jié)構(gòu)應(yīng)力值達(dá)到最大時約為對應(yīng)箱型結(jié)構(gòu)受采動影響前的1.20倍~2.50倍之間,但無扶壁箱型結(jié)構(gòu)的應(yīng)力值約為同條件下帶扶壁箱型結(jié)構(gòu)應(yīng)力值的3.0倍。采動影響除下沉外還有傾斜和曲率,由于該箱型結(jié)構(gòu)的橫向尺寸較小,縱向設(shè)置了變形縫,因此本文中僅考慮了橫斷面上均勻傾斜對箱型結(jié)構(gòu)的影響。兩種結(jié)構(gòu)形式箱型結(jié)構(gòu)模型應(yīng)力整體上隨斜率的增大,呈現(xiàn)先增大后減小的趨勢,一般在斜率為30‰或40‰時應(yīng)力達(dá)到最大。在地表傾斜作用下無扶壁箱型結(jié)構(gòu)應(yīng)力為帶扶壁箱型結(jié)構(gòu)應(yīng)力的2.30~3.00倍。因此扶壁結(jié)構(gòu)對箱型結(jié)構(gòu)起到很好的保護(hù)作用,得出帶扶壁箱型結(jié)構(gòu)較無扶壁箱型結(jié)構(gòu)的承載能力有很大提高。帶扶壁箱型結(jié)構(gòu)在續(xù)建的過程中,還會受到續(xù)建次數(shù)和建成后頂板和側(cè)墻是否澆筑為一體對箱型結(jié)構(gòu)應(yīng)力影響。該箱型結(jié)構(gòu)在采動影響下要續(xù)建3次,對每次續(xù)建后的模型進(jìn)行數(shù)值分析,得到箱型結(jié)構(gòu)隨續(xù)建次數(shù)增加的應(yīng)力演化規(guī)律:箱型結(jié)構(gòu)側(cè)墻的拉應(yīng)力和X方向的應(yīng)力在第一次續(xù)建后達(dá)到最大值,側(cè)墻壓應(yīng)力隨著續(xù)建次數(shù)而逐漸減小;箱型結(jié)構(gòu)底板應(yīng)力在第一次續(xù)建后達(dá)到最小,然后隨著續(xù)建又逐漸增大。對比分析箱型結(jié)構(gòu)頂板和側(cè)墻閉合和不閉合模型,得出箱型結(jié)構(gòu)采用搭板形式對結(jié)構(gòu)較為有利。最后本文就該箱型結(jié)構(gòu)的鋼筋連接方法和箱型結(jié)構(gòu)回填土先后順序進(jìn)行優(yōu)化,得到箱型結(jié)構(gòu)鋼筋連接采用直螺紋連接方法較為合理,且給出了相應(yīng)的實施方案;續(xù)建完成以后,應(yīng)先回填箱型結(jié)構(gòu)內(nèi)側(cè)土體,更有利于保證箱型結(jié)構(gòu)安全。
[Abstract]:Bridge and culvert is an important way to connect traffic. As an important structural form to resist deformation, box structure is especially important in mining area, although box structure is widely used in mining area. There are many researches on the bearing capacity and mining deformation resistance of box structure, but there are few researches on the sustainability of box structure. Most of them are over water box culverts. In this paper, the box structure under the special railway line of North District of a mine is taken as an example. Because the total height of the box structure is 11.6 m, the ordinary box structure can not meet the bearing requirements, this paper refers to the design of retaining wall with supporting wall. In this paper, the box structure without supporting wall and the box structure with supporting wall are taken as the research objects, and the software ANSYS is used to analyze the thickness of the box structure in the ballast. Under the influence of inclination, the stress variation law is analyzed. Then, the bearing characteristics and the reasonable roof structure form of the box structure with buttress are analyzed under the influence of the continuous construction factors. The construction method of box structure is optimized. Under the influence of mining, the box structure increases with the thickness of ballast. When the maximum stress values of the two structures reach the maximum value, it is between 1.20 times and 2.50 times of the corresponding box structure before the mining. However, the stress value of the unsupported box structure is about 3.0 times of that of the box structure with supporting wall under the same conditions. Besides subsidence, mining affects the slope and curvature of the box structure, because the transverse size of the box structure is small. In this paper, only the influence of uniform tilting on the box structure is considered. The stress of the two types of box structure model increases with the slope as a whole. There is a tendency to increase first and then decrease. In general, the stress reaches the maximum when the slope is 30 鈥，

本文編號：1437170