1、深基坑支護論文：成都市百揚大廈深基坑支護數值模擬研究【中文摘要】隨著經濟環境的發展與人們居住環境要求的提高,近年來我國建筑、市政等工程得到飛速發展。在都市中,寸土寸金,因而在建筑向高空發展的同時,地下空間的利用也成為一個重要方向。這些地下空間和設施,包括高層及多層建筑的地下室、地下商業街、地下車庫、地鐵車站、越江隧道等各種形式。開發和建造這些地下空間和設施,首先要進行的就是大規模的深開挖,因此,作為保障深開挖進行的深基坑工程技術也得到了不斷的發展。本文以百揚大廈深基坑工程為依托,就基坑的土壓力、支護方案、支護結構參數等進行了較為全面的研究,獲得了以下研究結果：(1)在分析傳統土層物理力學參數厚

2、度加權簡化方法存在的不足之處后,從支護結構內力等效的角度出發,提出了坑壁土層物理力學參數與支護結構內力等效相對應的簡化計算原理與方法,并與傳統土壓力計算方法的計算結果進行了對比分析,表明本文提出的簡化方法更為合理;(2)針對粘聚力較大的土層,用等值梁法來分析樁錨結構時尋求反彎點的困難,提出了等彎矩法來確定錨拉樁支撐點的位置及其支撐力值,經本基坑工程的論證,該方法效果較好；(3)運用有限差分軟件FLAC3D,對深基坑開挖支護的全過程進行了三維模擬,分析了六種工況下圍護結構的受力特性,研究了深基坑的變形規律。圍護樁最大水平位移計算結果和監測結果基本一致;(4)深基坑工程空間效應FLAC分析表明：圍

3、護結構變形呈現出較強的空間效應,基坑中部的圍護結構水平位移最大,越靠近基坑的角點,圍護結構的水平位移越??；水平支撐軸力分布也呈現出明顯的空間效應,位于基坑中部的水平支撐軸力最大,離角點越近,水平支撐軸力越小。研究結果表明三維計算是分析深基坑空間效應的有效手段。【英文摘要】In recent years, Chinese construction and municipal engineering have been developing rapidly with the development of economic environment. In the city, because of t

4、he high cost of land, the use of underground space has become an important direction. The underground space and facilities, including the basement level and multi-storey buildings, underground shopping street, underground garage, subwaystations, and other forms of cross-river tunnel. Construction of

5、 the underground space and facilities, the first step is the large-scale excavation, therefore, as a guarantee of deep excavation of the deep excavation technology has been continuously developing.This text research on the earth pressure、bracing scheme and the parameter of the bracing structure rely

6、ing on this deep foundation ditchengineering.The main results gained can be summed up as follows:(1)Analyse the existed shortage of the thickness weighted simplified method about the physieal meehaniealparameter of the soil horizons first and then starting from theangle of equivalent internal force

7、of the bracing strueture, extraet the simplified ealculation Prineiple and method which is corresponding to the physieal mechanical parameter of the soil horizons and equivalent internal force of the bracing strueture.Comparing with the results which are ealculatedaccording to the traditional earth

8、pressure ealculation method, it indicate that the simplificd method extraeted in this text is more appropriate.(2)Aim at the diffieulty of looking for inflection point when using equivalent beam method to analyse the pile anehor strueture in soil horizons with high cohesive strength, extract mapping

9、 method and equivalent bending moment method to ensure the location and value of the bracing.The effect is yerified preferably in this foundation ditchengineering.(3) By the use of finite difference software FLAC3D, a three-dimensional simulation of the entire process ofexcavation and support of dee

10、p excavation is accomplished.The behavior of retaining structure is analyzed, and thedeformation laws of deep excavation is studied in six cases. Monitoring results and calculation results of the largest horizontal displacement of retaining pile are basically the same.(4) The spatial effect of deep

11、excavation is analyzed by FLAG, the result shows that:the spatial distribution of thebracing structure displacements and the axial force of the steel support has strong spatial effect:Spatial effect of the corner is strong.and the spatial effect of The central section weakens.the result show that th

12、e calculation ofthree-dimensional analysis of deep excavation is an effective means to study spatial effect.【關鍵詞】深基坑支護 工程地質條件 有限差分法 FLAC3D 數值分析 土壓力【英文關鍵詞】deep foundation pit bracingEngineering geological conditions Finite difference method FLAC3D Numerical analysis Soil pressure【目錄】成都市百揚大廈深基坑支護數值模擬研

13、究6-710-11Abstract7第一章 緒論10-14摘要1.1 引言1.3 1.2 深基坑工程的主要內容與特點11-12國內外研究現狀121.4 本論文的主要研究工作12-142.1 工程概第二章 百揚大廈深基坑工程環境條件概況14-20況1414-16標16-17與難點17-202.2 工程環境條件14-172.2.2 場地地下水162.2.1 工程地質條件2.2.3 土層的工程特征指2.3 本基坑的特點3.1 常用2.2.4 場地的周邊環境17第三章 基坑土壓力分析20-323.1.1 朗肯土壓力理論的土壓力理論20-2621-233.1.2 庫倫土壓力理論23-243.1.3 基坑

14、水壓力的計算24-253.1.4 根據建筑基坑支護技術規程3.2 坑壁土壓力計算方3.2.2(JGJ120-99)的土壓力計算方法25-26法的分析26-283.2.1 地面荷載的處理26-27朗肯理論和庫倫理論的對比分析27-28算28-313.4 本章小結31-3232-4532-333.3 坑壁土壓力的計第四章 百揚大廈深基坑4.2工程支護方案研究基坑支護的技術要求33-444.1 基坑支護的功能324.3 基坑支護設計計算4.3.1 基坑設計簡述33-344.3.2 基坑支護結構的靜力計算34-37計算37-444.3.3 百揚大廈深基坑支護結構的靜力第五章 百揚大廈深基4.4 本章小結44-45坑支護的數值模擬分析45-67介45-485.1 有限差分法的基本原理簡5.2.1 5.35.2 有限差分法軟件FLAC_(3D)48-505.2.2 FLAC_(3D)的特點48-505.3.1 土體本構模型的確立FLAC_(3D)簡介48數值模型的建立50-5750-52件52-5353-575.3.2 計算區域及單元劃分、材料參數、邊界及初始條5.3.3 圍護樁、襯砌及預應力錨索的模擬5.4 基坑開挖模擬