摘要
以恒应变速率增长的等幅动应变的动力作用模式，对－５℃饱水黄土进行振动试验，揭示了动力作用对强度的影响。与静强度试验相比较，由于动力作用的速率效应和循环效应的综合影响的结果，在小的中值应变速率下，破坏提前，破坏应变减小，动强度降低；而在大的中值应变速率下，破坏推迟，破坏应变增大，动强度提高。在试验范围内，振频对动强度的影响微弱，而且在大、小两个中值应变速率区的影响趋向相反。似存在动、静强度相当。
Vibrating tests on saturated loess were carried out with equiamplitude dynamic strain increased with constant strain rate at -5℃, which revealed an effect of dynamic loading on strength. As compared with static test, the dynamic strength is lower, the failure time is moved up and the strain for failure is less when the median strain rate is low; but the dynamic sstrength is higher, thefailure time is delayed and the strain to failure is more when the median strain rate is high, showing an integrated influence of rate effect with cyclic effect. In the tested range the effect of vibrating rfrequency on the dynamic trength is feeble, and is positive when median strainrate is low and negative when median strain rate is high. It appears that there is a critical strain rate, under which the dynamic strength is not affected by vibration frequency and approximates to the static strength.
出处
《冰川冻土》
CSCD
北大核心
1996年第2期162-169,共8页
Journal of Glaciology and Geocryology
关键词
振动荷载
冻土
动力学
粉土
冻结
单轴抗压强度
Dynamics of frozen soil, dynamic strength, dynamic strain, rate effect,cyclic effect
