Abstract: In order to sum up structure geology and engineering geology of project area in Xiao-wan by the numbers, the author summarizes it on the base of pre-researchers production. The summarizing includes two parts, that is structure geology and engineering geology, and the paper stands out the keystone and core content respectively. The structure geology content consists of zone of fracture, fault, joint, structural stress field and seism. However, engineering geology summarizing includes terrain, lithology, geological action, hydrogeology and alteration of rock body and so on.
Abstract: For current engineering of anti-slide piles, many problems exist in the calculation of landslide-thrust. Therefore, a new method based on the reliability theory combined with strength reduction FEM is introduced, and the landslide-thrust acting on anti-slide pile is researched here. In this method, the safety factor of slope can be caculated without assuming the shape and position of failure surface beforehand, the randomness of physical and mechanical parameters of slope are introduced, and the combined action of retaining structure and rock mass is considered. Meanwhile, the thrust distribution form and structural internal force can be calculated, which are also probabilistic. A case study shows that the calculation results are more reasonable and the applicability of proposed method is clearly dependable in calculating the landslide thrust.
Abstract: The response characteristics to the seismic action of displacement for abutment are the important part of security evaluation, earthquake resistance and disaster mitigation in the seismic region. This paper decomposes the displacement of abutment into the slip displacement and rotation displacement two parts, respectively proposes the translational and rotational displacement model of abutment and establishes the corresponding calculation formulas. The case analysis indicates that the response characteristics of abutment displacement to the seismic action are comparatively sensitive, in which the translational displacement appears positive response relationship with the acceleration of seismic, while the rotational displacement appears negative response relationship. However, it holds significant mutation from 0.5g to 0.6g for both of the translational displacement and rotational displacement. In other words, the seismic acceleration from 0.5g to 0.6g should be paid highly attention in doing seismic resistance design in the seismic region.
Abstract: In this research, laboratory pullout tests were conducted on grouted soil nails to study the effect of wetting on the interface shear resistance between nail and soil during pullout. Deformed bars with equal size to the true soil nails were used as model nails. The soil used was silty fine sand collected at the site and prepared to a very dense condition. Rainfall infiltration was simulated using duplicated soil nails inundated by water for different periods. Test results indicated that the peak pullout resistance strongly decreases upon wetting, with a reduction of about 60% after soaking for 28 days. However, the experiments showed that there is a threshold water content (or soaking time) beyond which the effect of infiltration on the pullout resistance is reduced. The laboratory protocols developed in this study offered an easy scheme for the prediction of the pullout capacity of a grouted soil nail upon wetting.
Abstract: In order to study the evolvement of rock coastal in Hebei Province, the data was taken to study the evolved stations, such as relief maps, charts, remote sensing imagines and the field data of different areas from 1956 to 2007. With 3 S technology, it analyzed the evolvement processing and reasons of the rock coast by construction of coastal engineering in half century. The results were shown that it was changed strongly by the station from 1979 to 2007 when the station stopped the littoral current caused by coastal engineering such as Qinhuandgao Port and Shanhaiguan Shipyard. As the result, the section was deposited in the east of Qinhuangdao Port while eroded in the west. And the highest erosion speed was 2.49 m/a in the section from Xinkaihe River to South Mountain shipside. The angle was about 60°~80° from between middle bay and east bay. By the transport yield reduce of Tanghe River and Chituhe River, the coastline was eroded by NNE and ENE waves. Without the supply of sediment from the east bay and middle bay where were eroded seriously, the erosion speed was above 3.26 m/a, and the section was eroded fast with the speed of 3.67 m/a between Jinshan Mountain and Tiger Stone in west bay.
Abstract: For the prediction of the height of the fractured zone developed in mining with fully-mechanized top-coal caving system, the traditional calculation method, if used, generally yield a value with a comparatively large error. Based on mining condition of 6206 face at Wangzhuang Coal Mine in Luan mining area, a comprehensive study is made in the paper of the characteristics of the development of the fractured zone in the medium hard overlying strata under such full-seam mining conditions by taking various means, including field measurement and numerical and physical simulation. Through comparison with the field measurement data available and regression analysis, it can be seen that the height of the fractured zone developed in the medium hard overlying strata in mining with fully-mechanized top-coal caving system is directly proportional to the total mining thickness. In comparison with the result obtained with the use of empirical formula, the method used in the paper can better bring to light the occurrence of the intensive failure of overlying strata under such a mining condition. The research-derived achievement can serve as a basis for reference for the prediction of the height of fractured zone in mining under medium hard cover by using fully-mechanized top-coal caving method, and for decision making in mining under a water body.
Abstract: The key problem which the control of landslide hazard is the prediction of landslide fatalness, successful landslide forecast can consumedly decrease the loss caused by landslide hazard. Landslide spatial forecast can determine the location of unstable slope. For a certain landslide in Three Gorges Reservoir area, according to the existing monitoring data and analysis methods, such as: nonlinear regression analysis method, exponential smoothing and gray prediction method, to forecast deformation tendency of landslide from quantitative point and take comparative study. Results indicate that the gray prediction method is more tally with the reality in the deformation prediction. It can provide reference for deformation forecast of similar landslide or slope prevention in chongqing and Three Gorges Reservoir area.
Abstract: Taking into account the narrow terrain, the proposed highway has to be built near the reservoir in the study area of metamorphic rock. Furthermore, part of the tunnel elevation is lower than the reservoir of a hydropower station. If the horizontal distance between the reservoir and tunnel is far enough and the differential head is large enough, it is likely that the serious leakage of the hydropower station reservoir will occur. The interaction between highway construction and reservoir is to be the key point. Either the safety of tunnel construction and operation or the safety of reservoir storage is important. This paper use the Darcy’s law and the hydrogeological characteristics of metamorphic rock to estimate the lateral seepage and evaluate the line design.
Abstract: In this paper, the Block Element Method (BEM) for dynamic analysis is developed and applied to historical analysis of seismic stability of a rock slope. Combine the idea of viscous-spring boundary with the theory of BEM, the artificial boundary condition of BEM is formulated, which can eliminate reflection of the seismic waves from the boundaries of the calculating domain. Also, the relationship between the displacement and the stiffness of discontinuous is adopted in the dynamic block element method. The corresponding program is written by FORTRAN language and the application of the intake slope demonstrates the capacity of this method.
Abstract: The loads on the arch dam and the materials physical properties of the dam and the bedrock are uncertain, and can be described with random variable. Due to the huge volume, the complex structure of the dam and excessive random variable, the reliability analysis of the dam is difficult. The dam is a higher order statically indeterminate structure, and the variation of the temperature obviously affects the stress and displacement of the structure, therefore, it is very important to consider the randomness of the temperature change load in the reliability analysis of arch dam. Based on the analysis of the stable temperature field, temperature rise and temperature drop field of the dam, the calculation method of temperature change field is further studied and applied in the reliability analysis of the arch dam. Considering random variables such as temperature change, water pressure, elastic modulus and strength of the materials, the stress and displacement of the arch dam and bedrock are calculated with a three dimensional finite element method, the limit state equations are established by RSM. Then the tension and compression reliability of the arch dam are analyzed using gradient optimization method. The results indicate that the temperature change field significantly influences the tension and compression reliability of the dam, and should be seriously considered in the reliability analysis of arch dams.