本文選題：基坑開挖　切入點：地下水　出處：《南昌航空大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

【摘要】：在高地下水位地區(qū)進行基坑開挖時,為降低地下水位對基坑穩(wěn)定性的影響,常需進行基坑降水施工,由于基坑降水會誘發(fā)土體的固結(jié)變形,進而對臨近建筑物的安全狀態(tài)產(chǎn)生不利的影響。對此,本文設(shè)計了一種防滲水基坑支護結(jié)構(gòu),通過室內(nèi)試驗和仿真分析相結(jié)合的方法,對設(shè)計結(jié)構(gòu)性能及影響因素進行分析,主要得到以下研究成果:(1)針對基坑降水誘發(fā)土體變形問題,本文設(shè)計了一種防滲水基坑支護結(jié)構(gòu),該結(jié)構(gòu)在基坑側(cè)壁設(shè)置豎向截水層,在基坑底部設(shè)置坑底截水層,形成三維密封的防滲體系,從結(jié)構(gòu)特點及受力機理來看,該結(jié)構(gòu)可以有效的阻斷地下水的滲透路徑,減小基坑外側(cè)土體的變形。(2)根據(jù)所提出的防滲水基坑支護結(jié)構(gòu),開展室內(nèi)模型試驗,對基坑外不排水開挖和基坑外排水開挖兩種工況下,土體變形、支護結(jié)構(gòu)變形和支護結(jié)構(gòu)應(yīng)力進行測試,從測試結(jié)果來看,兩種工況下土體位移、支護結(jié)構(gòu)位移與支護結(jié)構(gòu)的應(yīng)力存在一定的差異。從影響幅度來看,基坑外不排水開挖相對于基坑外排水開挖,土體豎向位移減小了約50%;土體水平位移減小了約20.3%;支護結(jié)構(gòu)的位移增大了約20%;支護結(jié)構(gòu)的應(yīng)力增大了約25%。(3)根據(jù)設(shè)計結(jié)構(gòu)性能仿真分析結(jié)果,發(fā)現(xiàn)各因素改變都會對支護結(jié)構(gòu)性能和周邊土體變形產(chǎn)生影響。從對支護結(jié)構(gòu)性能影響來看,支護結(jié)構(gòu)高度和支護結(jié)構(gòu)剛度對支護結(jié)構(gòu)性能影響較大,水頭差和墻背土性對支護結(jié)構(gòu)性能影響較小。從對基坑周邊土體變形影響來看,水頭差對土體變形影響較大,支護結(jié)構(gòu)高度和支護結(jié)構(gòu)剛度對土體變形影響較小。
[Abstract]:In order to reduce the influence of groundwater level on the stability of foundation pit during excavation in high groundwater level area, it is often necessary to carry out foundation pit dewatering construction, because foundation pit dewatering will induce consolidation deformation of soil. In this paper, a kind of seepage proof foundation pit supporting structure is designed. Through the combination of indoor test and simulation analysis, the performance of the design structure and its influencing factors are analyzed. In order to solve the problem of soil deformation induced by dewatering of foundation pit, this paper designs a kind of impervious foundation pit supporting structure. The structure has vertical water intercepting layer on the side wall of foundation pit, and bottom water intercepting layer on the bottom of foundation pit. According to the structure characteristics and mechanical mechanism, the structure can effectively block the seepage path of groundwater and reduce the deformation of soil outside the foundation pit. The indoor model test was carried out to test the soil deformation, support structure deformation and support structure stress under the two conditions of undrained excavation outside the foundation pit and drainage excavation outside the foundation pit. From the test results, the displacement of the soil under the two working conditions was analyzed. There are some differences between displacement of supporting structure and stress of supporting structure. In terms of influence range, undrained excavation outside foundation pit is relative to drainage excavation outside foundation pit. The vertical displacement of the soil is reduced by about 50 percent; the horizontal displacement of the soil is reduced by about 20.3; the displacement of the supporting structure is increased by about 20; the stress of the supporting structure is increased by about 25.3; It is found that the change of various factors will affect the performance of the supporting structure and the deformation of surrounding soil, and the height of the supporting structure and the stiffness of the supporting structure will have a great effect on the performance of the supporting structure. The difference of water head and the soil property of the back of the wall have little influence on the performance of the supporting structure. From the effect on the deformation of the soil around the foundation pit, the difference of the water head has a great influence on the deformation of the soil, and the height of the supporting structure and the stiffness of the supporting structure have little effect on the deformation of the soil.
【學(xué)位授予單位】：南昌航空大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TU753

【參考文獻】

相關(guān)期刊論文 前10條

1 李偉;童立元;王占生;劉松玉;;地鐵車站不同工況減壓降水對環(huán)境的影響[J];解放軍理工大學(xué)學(xué)報(自然科學(xué)版);2014年03期

2 黃新;宋漢周;;基于降水優(yōu)化方案的基坑地面沉降數(shù)值模擬[J];勘察科學(xué)技術(shù);2013年01期

3 周念清;魏誠寅;婁榮祥;繆俊發(fā);;上海地鐵M4線修復(fù)的深基坑降水應(yīng)急預(yù)警體系[J];湖南大學(xué)學(xué)報(自然科學(xué)版);2012年12期

4 姚紀(jì)華;宋漢周;彭鵬;霍吉祥;;深基坑降水引起地面沉降的影響因子權(quán)重體系[J];勘察科學(xué)技術(shù);2012年06期

5 劉登攀;;建筑物超載對深基坑周邊地表沉降影響分析[J];探礦工程(巖土鉆掘工程);2012年06期

6 蔣麟;王雷;;基坑開挖及支護的影響分析[J];華章;2011年21期

7 江曉峰;劉國彬;張偉立;李翔宇;;基于實測數(shù)據(jù)的上海地區(qū)超深基坑變形特性研究[J];巖土工程學(xué)報;2010年S2期

8 林川;周丁恒;曹力橋;;考慮滲流固結(jié)耦合作用的軟土深基坑降水施工的三維數(shù)值[J];隧道建設(shè);2010年S1期

9 范士凱;楊育文;;長江一級階地基坑地下水控制方法和實踐[J];巖土工程學(xué)報;2010年S1期

10 王建秀;吳林高;胡力繩;李國;唐益群;楊坪;許旭;婁榮祥;;復(fù)雜越流條件下超深基坑抽水試驗及工程應(yīng)用[J];巖石力學(xué)與工程學(xué)報;2010年S1期

相關(guān)博士學(xué)位論文 前1條

1 劉濤;基于數(shù)據(jù)挖掘的基坑工程安全評估與變形預(yù)測研究[D];同濟大學(xué);2007年

相關(guān)碩士學(xué)位論文 前2條

1 趙陳鵬;軌道交通9號線宜山路站基坑降水對地面沉降的影響及室內(nèi)模型試驗研究[D];同濟大學(xué);2007年

2 張亞奎;深基坑開挖對近鄰建筑物變形影響的研究[D];北京工業(yè)大學(xué);2003年

，

本文編號：1616723