(1. Chongqing Key Laboratory of Geomechanics and Geoenvironment Protection，Logistical Engineering University，Chongqing 401311，China；2. School of Civil Engineering and Architecture，Chongqing University of Science and Technology，Chongqing 401331，China)
Abstract：The microstructure characteristics of loess，especially Q2 loess，at Pucheng power plant in Shaanxi Province were investigated using Quanta environment scanning electron microscope(ESEM). Consequently，various microstructure pictures were obtained. The four forms of particle connections，i.e. direct point contact，direct face contact，indirect point contact and indirect face contact，are suggested. The microstructure quantitative analysis results of loess show the area proportion，the orientation and the distribution fractal dimensions of particles increase with depth. Whilst the area proportion，the orientation and the distribution fractal dimension of pore，and the Euler value decrease with depth. However，the number and the roundness of particle，the number of pore，and the gray entropy have not significant change law with depth. The microstructure characteristics and the collapsibility of Q3 and Q2 loesses have a good relationship.
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2013, Vol. 32 
