【摘要】：本文通過滲透試驗(yàn)確定了影響寬級(jí)配土滲透性的細(xì)顆粒上限粒徑及細(xì)顆粒含量與滲透系數(shù)的關(guān)系,再通過揚(yáng)壓力模型試驗(yàn)得出溝床滲透系數(shù)與揚(yáng)壓力的關(guān)系,結(jié)合兩試驗(yàn)結(jié)果綜合得出寬級(jí)配土中細(xì)顆粒含量與壩底揚(yáng)壓力的關(guān)系,可為攔砂壩設(shè)計(jì)中揚(yáng)壓力計(jì)算與控制提供一定的理論依據(jù)。取得的主要研究成果如下:(1)確定了影響泥石流寬級(jí)配土滲透性的細(xì)顆粒上限粒徑。顯著影響寬級(jí)配土滲透性的細(xì)顆粒上限粒徑為0.1mm。(2)研究了細(xì)顆粒含量與土體滲透系數(shù)的關(guān)系。細(xì)顆粒含量p與土體滲透系數(shù)k呈負(fù)指數(shù)關(guān)系,關(guān)系式為k=ne-p/m,式中n與粗顆粒滲透性有關(guān),m與細(xì)顆粒的滲透性有關(guān)。(3)分析了壩底揚(yáng)壓力的分布特征。壩底揚(yáng)壓力P與通過溝床滲流路徑L呈反比,關(guān)系式為P=a-b L,式中a與壩前水頭高度及壩前堆積情況有關(guān),小于壩前水壓力,b與溝床坡度及溝床的滲透系數(shù)有關(guān)。(4)探討了壩底揚(yáng)壓力與滲透系數(shù)的關(guān)系。壩底揚(yáng)壓力P與壩前堆積物的滲透系數(shù)的常數(shù)對(duì)數(shù)lgk呈正比,關(guān)系式為P=a+b lgk,a與壩前水位及溝床坡度有關(guān),b與溝床坡度有關(guān)。壩底揚(yáng)壓力P與溝床物質(zhì)滲透系數(shù)系數(shù)k呈正比,關(guān)系式為P=a+bk,a與壩前水位及溝床坡度有關(guān),b與溝床坡度有關(guān)。(5)初步建立了泥石流寬級(jí)配土中細(xì)顆粒含量與揚(yáng)壓力的關(guān)系。細(xì)顆粒含量通過影響滲透系數(shù)來影響壩底揚(yáng)壓力。壩底揚(yáng)壓力P與細(xì)顆粒的百分含量p呈負(fù)指數(shù)關(guān)系,關(guān)系式為=+-/,式中y與壩前水位有關(guān),A與粗顆粒滲透性及溝床坡度有關(guān),c與細(xì)顆粒的滲透性有關(guān)�？赏ㄟ^降低壩前的水頭及壩底溝床物質(zhì)滲透系數(shù)是來減小壩底揚(yáng)壓力。增加溝床物質(zhì)中的細(xì)顆粒含量可明顯是降低溝床物質(zhì)滲透系數(shù),是有效減小揚(yáng)壓力的可行方法。
[Abstract]:In this paper, the relationship between the upper particle size and the content of fine particles and the permeability coefficient is determined by the permeability test, and the relationship between the permeability coefficient and the uplift pressure of the furrow bed is obtained by the model test of the uplift pressure. Combined with the results of the two tests, the relationship between the content of fine particles in the wide gradation soil and the uplift pressure at the bottom of the dam is obtained, which can provide a certain theoretical basis for the calculation and control of the uplift pressure in the design of the sand retaining dam. The main research results are as follows: (1) the upper particle size of fine particles affecting the soil permeability of debris flow with wide gradation is determined. The upper particle size of fine particle is 0.1mm. (2) the relationship between the content of fine particles and the permeability coefficient of soil is studied. There is a negative exponential relationship between fine particle content p and soil permeability coefficient k, in which n is related to the permeability of coarse particles and m is related to the permeability of fine particles. (3) the distribution characteristics of uplift pressure at the bottom of dam are analyzed. The bottom uplift pressure P is inversely proportional to the percolation path L through the trench bed, and the relation is P=a-b L, in which a is related to the head height in front of the dam and the accumulation in front of the dam, and is smaller than the water pressure in front of the dam. B is related to the slope of the trench bed and the permeability coefficient of the trench bed. (4) the relationship between the uplift pressure at the bottom of the dam and the permeability coefficient is discussed. The uplift pressure P of dam bottom is proportional to the constant logarithmic lgk of the permeability coefficient of the deposit in front of the dam. The relation is that the lgk,a is related to the water level in front of the dam and the slope of the trench bed, and b to the slope of the trench bed. The uplift pressure P at the bottom of the dam is proportional to the material permeability coefficient k of the trench bed, and the relation is that Pu a bk,a is related to the water level in front of the dam and the slope of the trench bed. B is related to the slope of trench bed. (5) the relationship between fine particle content and uplift pressure of debris flow soil with wide gradation is preliminarily established. The content of fine particles affects the uplift pressure of dam bottom by influencing the permeability coefficient. There is a negative exponential relationship between the uplift pressure P at the bottom of the dam and the percent content of fine particles p, the relation is =-/, the y is related to the water level in front of the dam, A is related to the permeability of coarse particles and the slope of the trench bed, c is related to the permeability of fine particles. The uplift pressure can be reduced by reducing the water head in front of the dam and the material permeability coefficient of the bottom trench bed. Increasing the content of fine particles in the furrow bed can obviously reduce the permeability coefficient of the material in the trench bed and is a feasible method to reduce the uplift pressure effectively.
【學(xué)位授予單位】：西南科技大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：P642.23

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 金秋;陳新杰;;棉花灘大壩揚(yáng)壓力綜合分析[J];人民黃河;2010年03期

2 玉柏源;鹽鍋峽大壩壩底揚(yáng)壓力原型觀測(cè)成果分析[J];水利學(xué)報(bào);1982年12期

3 邱賢德,閻宗嶺,劉立,王輝;堆石體粒徑特征對(duì)其滲透性的影響[J];巖土力學(xué);2004年06期

，

本文編號(hào)：2412013