Frictional resistance characteristic and critical frictional resistance strength of geosynthetics in sandy soil are gotten by pullout test for five geosynthetics material.

This paper analyzes mechanism of concrete early frost damage,discusses its expression and its permissible critical strength,and introduces application of the critical strength combined with practical engineering.

As a result, the critical strength can not be decided by it.

This paper uses the mechanical model,in which the relationship between minimal displacement Δx and coefficient of rolling resistance δ is linear,to discuss constitutive relation of bodies with non critical rolling resistance,the equation M=δ f0 ·Δx·N is established This equation may be used to solve the statically indeterminate problem with rolling resistanc

The threshold friction velocity of oasis surface is greater than that of Gobi surface at natural condition, and the vertical dust flux of oasis surface is nearly 10 times smaller than that of Gobi surface because of the difference of the land-surface characteristics such as particle size distribution, plant vegetation and surface soil moisture content and so on, but whe.

The dust particle concentration data measured by Wide Range Particle Spectrometer and the data observed at a 20 m meteorological tower were used to calculate the dust emission rate,friction velocity and threshold friction velocity over Zhurihe area,Inner Mongolia.