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It is crucial for design and safety of the cementing sheath to develop better understanding of the CaCO 3 whisker reinforced oil well cement pastes. The uniaxial compression curve, mechanical constitutive relation, and reinforcing mechanism of the CaCO 3 whisker reinforced oil well cement pastes are studied in this script. The results indicate that the CaCO 3 whisker under the 10% dosage could improve the tensile strength of the cement paste significantly. The peak stress, elasticity modulus, and the energy at different stages of the stress-strain curve of the CaCO 3 whisker reinforced cement paste are reinforced with the increasing of CaCO 3 whisker. Afterward, the constitutive model of stress-strain curve, the toughness index, and capability coefficients index of the CaCO 3 whisker reinforced cement paste are established. A physical model of the interface layer is also established and the micromechanical reinforcement is related to the double film layer between the CaCO 3 whisker and cement matrix which could be bonded with much more fastness to the cement surface. The development of this script provides new ways to analyze the toughening mechanism of CaCO 3 whisker and establishes a correlation between basic material structure and the physical properties.

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Problems often encountered in karst atMountain city construction and other infrastructure construction. to find out the genesis model of karst is important to prevent accidents. But in many areas, there is few research about karst development pattern, such as dabashan mountain area described in this article.Through our study on the genetic model about karst geological park in the region, we provides a train of thought for karst problem of urban construction in this area in the future. This National Geological Park is located in Daba Mountain.This park is different with other karst areas about karst landform development formation.The reason may be that Daba mountain is in the transitional belt line of north karst landform and south karst landform of China.The terrain mountain high deep valley, on the ground reconnaissance was carried out on the karst landform is hard to have overall grasp on karst, so we tried to use remote sensing images of karst scenic spot as auxiliary analysis, and has obtained the good effect. Remote sensing image interpretation can not only improve the efficiency of the understanding of karst development situation, at the same time due to a greater range of observation and analysis of karst scenic spot, the depth of understanding of the karst development through the analysis of the remote sensing images will also be greatly improved. Based on the remote sensing image formation patterns of karst scenic spot was analyzed.We think that Ba Taishan steep cliff is a residual funnel development under the planation surface. And Ba Taishan steep cliff is tangency to the long axis wall of the residual funnel, so the steep terrain appears more spectacular.