In order to study the influence of freezing-thawing cycles on shear strength of seasonal frozen soil in northeast China, silty clay, typical soil in Jilin region, was selected. 20 groups of specimens were carried out by quick shear tests considering soil water content and the number of freezing-thawing cycling. The test results indicate that soil cohesion presents the slight fluctuation with the increase of water content, and the maximum value reaches around the peak of liquid limit. Internal friction angle of soil shows the sharp drop and the extent changes between 40% - 60%. The soil cohesion gradually declines with the increase of the number of freeze-thawing cycling. Therefore, the effect of the first freezing-thawing cycle on soil cohesion is obvious, and cohesion gradually tend to be stable after 7 freezing-thawing cycles. The final value of cohesion is approximate a third to a half of the unfrozen soil. The internal friction angle of soil increases with the augment of cycling number of freezing-thawing, which is related to the water content. The higher water content will bring about the greater growth rate of friction angle.

A series of tests were conducted with laboratory normal devices to investigate the engineering property of coal ash mixed with various clay contents. By analyzing experimental data, some conclusions were made: It is helpful to improve the compaction effect and significantly reduce the consumption of the water needed in engineering by mixing the clay into coal ash. The shear strength of coal ash decreased slightly with increase of clay content. The shear strength of coal ash mixed with the 30% clay content is nearly equal to that of pure coal ash. With the increase of clay content, the coefficients of compressibility a1-2 have a little irregularly growth. It always belongs to medium compressibility soils.

In traditional grating auto-stereoscopic displays,the head movement would lead to the crosstalk of 3D images. There is a way to minimize the crosstalk from utilizing eyes’ position to rearrang the RGB sub-pixels.In this paper, a method to detect the center of eyes which is based on black and white binary grating projection is proposed. After projecting periodic grating composed by black and white stripes from projector,the CCD intakes deformed stripes,using the offset which is compared the deformed fringe with the reference to restore facial contours. Recover the morphology conveniently from encoding every deformed stripe with an unique code. Experimental results show that this method requires less image,has strong anti-interference abilitity.It is easy to get the position of eyes’center after getting the face contour,so this method could be applied as a new way in the nose and face recognition and tracking fields.