發(fā)布時間：2018-12-13 02:04

【摘要】：采用專門設(shè)計的低溫共振柱儀進行試驗研究,研究典型土類動剪切模量阻尼比隨負溫的變化規(guī)律及計算方法。提出溫度影響系數(shù)的概念,并以較為符合實際的固結(jié)壓力和凍結(jié)過程,完成了黏土、粉土與砂土在常溫及不同負溫下的動力試驗,給出了這3種典型土類不同負溫下初始剪切模量、剪切模量比和阻尼比的計算公式。結(jié)果表明:無論何種土類,負溫對其初始剪切模量、剪切模量比和阻尼比都有重要影響,相應(yīng)的溫度修正系數(shù)按Boltzmann與指數(shù)函數(shù)變化,均在0℃到-6.0℃快速變化之后趨于平緩,但變化程度和修正公式中的參數(shù)均與土類有關(guān);隨溫度降低,3種土類初始剪切模量增長十分顯著,完全凍結(jié)黏土、粉土和砂土分別為常溫土初始模量的50倍、25倍和13倍;隨溫度降低,3種土類參考剪應(yīng)變降低十分顯著,但完全凍結(jié)后3種土的動剪切模量降低程度接近;隨溫度下降,3種土類最大阻尼比均顯著減小,完全凍結(jié)后的黏土最大阻尼比降幅最大,砂土降幅最小,粉土居中。3種典型土類負溫下動剪切模量阻尼比修正公式,其反映的現(xiàn)象和規(guī)律與國際上近期成果定性相符。
[Abstract]:The dynamic shear modulus damping ratio of typical soils with negative temperature is studied by means of a specially designed low temperature resonance column instrument. The concept of influence coefficient of temperature is put forward, and the dynamic tests of clay, silt and sand at normal and different negative temperatures are carried out with the practical consolidation pressure and freezing process. The formulas for calculating the initial shear modulus, shear modulus ratio and damping ratio of these three typical soils at different negative temperatures are given. The results show that the negative temperature has an important effect on the initial shear modulus, shear modulus ratio and damping ratio, and the corresponding temperature correction coefficient varies according to Boltzmann and exponential function. After changing rapidly from 0 鈩，

本文編號：2375673