本文選題：模袋砂圍堰　切入點(diǎn)：穩(wěn)定性　出處：《華南理工大學(xué)》2014年碩士論文

【摘要】：模袋砂圍堰由于施工簡便、污染少、機(jī)械化程度高、易于拆除等優(yōu)點(diǎn)被廣泛應(yīng)用于江、河、湖、海的近岸港灣、碼頭等臨時圍堰工程建設(shè)中。但由于模袋砂力學(xué)性狀的復(fù)雜性，目前對模袋砂圍堰的穩(wěn)定性分析、變形特性研究和模袋抗拉強(qiáng)度計算還有待完善。因此，本文在開展了模袋砂增強(qiáng)機(jī)理分析，室內(nèi)試驗研究的基礎(chǔ)上，對模袋砂圍堰進(jìn)行了穩(wěn)定性分析、斷面設(shè)計方法探討、變形特性研究及模袋抗拉強(qiáng)度計算。本文主要研究內(nèi)容及取得的成果如下： （1）分析了模袋砂增強(qiáng)機(jī)理，推導(dǎo)了模袋砂極限壓應(yīng)力理論解析解，進(jìn)行了模袋砂室內(nèi)單軸壓縮試驗和水平加載試驗，得到了模袋砂豎向、橫向應(yīng)力—應(yīng)變關(guān)系曲線，分析了模袋砂豎向、橫向力學(xué)性狀。分析結(jié)果表明，模袋砂并不是各向均質(zhì)體，橫向與豎向力學(xué)性狀并不相同，其水平變形模量遠(yuǎn)遠(yuǎn)小于豎向變形模量，且隨著上覆荷載的增大，模袋砂水平變形模量也逐漸增大。 （2）建立了模袋砂圍堰穩(wěn)定性分析簡化模型，提出了圍堰穩(wěn)定性計算方法，推導(dǎo)了圍堰穩(wěn)定性計算公式。以廣州市洲頭咀隧道第二次圍堰工程為背景，對不同坡度、不同頂寬模袋砂圍堰進(jìn)行了穩(wěn)定性計算，分析了模袋砂圍堰穩(wěn)定安全系數(shù)變化規(guī)律。分析結(jié)果表明，圍堰安全系數(shù)隨著坡度的變緩、頂寬的增大而增大，且圍堰穩(wěn)定由外部穩(wěn)定性控制。 （3）優(yōu)化了模袋砂圍堰穩(wěn)定性計算公式，對圍堰斷面設(shè)計方法進(jìn)行了探討研究；且從穩(wěn)定分析角度，在滿足穩(wěn)定安全系數(shù)要求時，推導(dǎo)了圍堰最小斷面面積計算公式；并運(yùn)用MATLAB數(shù)學(xué)軟件，編制了搜索圍堰最優(yōu)頂寬b和坡度i的程序代碼，提出了模袋砂圍堰最優(yōu)斷面設(shè)計的計算方法。 （4）結(jié)合廣州市洲頭咀隧道第二次圍堰工程設(shè)計及實(shí)施情況，對圍堰進(jìn)行了穩(wěn)定性驗算；建立了圍堰數(shù)值分析模型，研究了下游降水過程中圍堰的變形特性；結(jié)合模袋砂變形計算結(jié)果，對模袋進(jìn)行了抗拉強(qiáng)度驗算。結(jié)果表明，，模袋內(nèi)形成穩(wěn)定水位時，圍堰變形趨于穩(wěn)定；隨著下游水位的降低，圍堰變形逐漸增大，模袋拉應(yīng)力也隨之增大。 （5）總結(jié)了模袋砂圍堰的變形規(guī)律，提出了模袋砂圍堰的變形計算方法。將計算結(jié)果和實(shí)測值進(jìn)行了對比分析，對比結(jié)果表明文中建模方法的合理性和有效性。
[Abstract]:Due to the advantages of simple construction, less pollution, high mechanization and easy to be dismantled, the sand cofferdam is widely used in the construction of temporary cofferdam projects such as river, river, lake, sea near shore, wharf, etc. However, due to the complexity of mechanical properties of moulded bag sand, At present, the stability analysis, deformation characteristic research and tensile strength calculation of mold bag sand cofferdam need to be improved. The stability analysis, section design method, deformation characteristic research and tensile strength calculation of mold bag sand cofferdam are carried out. The main contents and results of this paper are as follows:. In this paper, the strengthening mechanism of mold bag sand is analyzed, the analytical solution of ultimate compressive stress is deduced, the uniaxial compression test and horizontal loading test are carried out, and the vertical and transverse stress-strain relationship curves are obtained. The vertical and transverse mechanical properties of moulded bag sand are analyzed. The results show that the sand is not homogenized in each direction, and its horizontal deformation modulus is much smaller than that of vertical deformation, and the lateral and vertical mechanical properties are different. And with the increase of overburden load, the horizontal deformation modulus of sand-bag sand increases gradually. (2) A simplified model for stability analysis of sand cofferdam with moulded bag is established, a method for calculating the stability of cofferdam is put forward, and a formula for calculating the stability of cofferdam is derived. Taking the second cofferdam project of Guangzhou Zhoutou Tunnel as the background, the slope of the second cofferdam is studied. The stability calculation of sand cofferdam with different top width is carried out, and the variation law of stability safety factor of sand cofferdam is analyzed. The results show that the safety factor of cofferdam increases with the increase of slope, and the width of sand cofferdam increases with the increase of top width. The stability of cofferdam is controlled by external stability. (3) the formula for calculating the stability of sand cofferdam is optimized, and the design method of cofferdam section is studied, and the formula for calculating the minimum section area of cofferdam is derived from the point of view of stability analysis when the requirement of stability safety factor is satisfied. The program code of searching the optimum top width b and slope I of cofferdam is compiled by using MATLAB software, and the calculation method of optimum section design of sand cofferdam with mould bag is put forward. 4) based on the design and implementation of the second cofferdam in Guangzhou City, the stability of the cofferdam is checked, and the numerical analysis model of the cofferdam is established, and the deformation characteristics of the cofferdam in the process of downstream precipitation are studied. Combined with the calculation results of sand deformation in mold bag, the tensile strength of die bag is checked. The results show that the cofferdam deformation tends to be stable when the stable water level is formed in the mold bag, and the cofferdam deformation increases gradually with the decrease of downstream water level. The tensile stress of die bag also increases. (5) the deformation law of sand cofferdam is summarized, and the method of calculating the deformation of sand cofferdam is put forward. The results are compared with the measured values, and the results show that the modeling method is reasonable and effective.
【學(xué)位授予單位】：華南理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TV551.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 林剛,束一鳴,林勇;充填管袋填筑的原理與實(shí)踐[J];人民長江;2005年02期

2 王文杰,余祈文,宋立松,陳森美;土工充泥袋拋壩促淤試驗研究與實(shí)踐[J];水利學(xué)報;2003年02期

3 張江保;;淺論模袋混凝土護(hù)坡施工技術(shù)——水下鋪灌法[J];中國西部科技;2009年17期

4 譚昌明,姜樸;擠淤法修筑防波堤穩(wěn)定性的試驗研究[J];巖土工程學(xué)報;1998年04期

5 唐洪祥;王海清;;土工織物補(bǔ)強(qiáng)軟基的作用機(jī)理與整體穩(wěn)定性分析[J];巖土力學(xué);2005年12期

6 劉斯宏;松岡元;;土工袋加固地基新技術(shù)[J];巖土力學(xué);2007年08期

7 劉偉超;張儀萍;楊艷;俞亞南;;任意對稱剛性地基上土工管袋充填形狀和受力分析[J];浙江大學(xué)學(xué)報(工學(xué)版);2011年07期

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