Advanced Materials Research Vols. 446-449

Abstract: The rock mass structure of granite is massive, so the stability of granite slope is good. Massive rock become stratoid structure when the rock mass contain discontinuities such as joints and faults. The deformation and destruction of the slope rock mass is controlled by the behaviour and orientation of the discontinuities. Especially, the over-dip discontinuities controlled the slope stability. In this paper, based on the abundant field investigation on the slope in left bank diversion tunnel inlets of Nuozadu power station in Lancang River, the types of rock mass structures and the combination between structural planes and slope surface are studied in detail so as to analyze the slope deformation mechanism. Finally, the slope stability is researched systematically by limit equilibrium method and FLAC numerical simulation analysis. A set of technical and methodological system on stability research of over-dip stratoid structure rock slope will hoped to be established.

Abstract: The complexity of the geological conditions and the non-uniformity of geotechnical material make the study of slope stability with big uncertainties, so it is necessary to analyze the reliability of slope. In this paper, firstly, the matrix suction of Malan loess in Gansu Province is measured by tension meter, and a fitted soil-water characteristic curve (SWCC) is obtained according to the empirical formula; then SWCC parameters of Malan loess such as a, n and θs (saturation volumetric water content) are thought as random variables, the method of simplified Bishop is used to calculate of slope stability, and the reliability of cutting slope of Malan loess is analyzed according to Rosenbleuth method. Through calculating, obtain mean factor of safety, failure probability and reliability index of the slope. After analyzing the relations between mean factor of safety, failure probability, reliability index and variability of parameters, the results show that, the factor of safety is 1.005 and it is stable when the variability of SWCC parameters are not considered. When variation coefficients of a, n and θs are all 0.3, the average factor of safety is 1.051, the reliability index is 10.94 and failure probability is 29.81%. It is obvious that variability of SWCC parameters has certain influence on stability of the slope. In parameters of SWCC, comparing with a and θs, the variability of n has the most important influence on the mean factor of safety and failure probability. But the corresponding reliability index is minimum (the change ratios of the mean factor of safety， failure probability and reliability index with variation coefficient of n are 0.37，3.247 and 282.0 respectively). So variation level of n should be specially taken into account in reliability analysis of the slope. This research provides an important basis for the determination of the SWCC parameters of Malan loess, the stability calculation, stability estimation and prevention sliding of loess cutting slope caused by rainfall.

Abstract: Luhuo County is located in the Xianshui river fault which is a famous strong activity fault in the southwest of china. In April 10, 2011 an earthquake measuring Ms=5.3 happened near the Luhuo County , the earthquake and its secondary effect had triggered a series of geo-hazards, making the previous fragile geological environment had further deterioration and significantly increased the earthquake disaster risk of the mountain town. There are four main factors influence and control the geological disaster risks of the county, including the strong shaking effect of the earthquake fault, Qiuri River debris flows in the southern city zone, the geological hazards of Se Delong gully in the northern city zone and the group-occurring flows which threaten the county roads.

Abstract: Tri-axial test is one of effective means to measure the strength of unsaturated soil. But because of complexity and exquisite requirement with and long duration of test, unsaturated tri-axial test wasn’t used extensively in civil engineering before. The tests of shear strength of unsaturated soil are performed with the improved tri-axial apparatus for unsaturated soil. According to test data, the relationship of strength between water content and matrix suction are studied. In addition, the new shear strength formula suitable for yellow river is derived. The formula is the theory basis for analysis of unsaturated slope stability.

Abstract: In the existing technology of cold asphalt pavement recycling, it is only the aggregate that is used again after the crushing and screening of the Reclaimed Asphalt Pavement (RAP), but the asphalt is discarded. So a lot of asphalt resource is wasted. The technology of emulsification and recycling of RAP in room temperature reuses the aged asphalt in the RAP thereby effectively reducing the quantity of newly added asphalt and also improving the performance of the mixture. The application of this technology will save a lot of valuable resources, reduce material costs and save project investments. The technology also contributes to the practice of “resource-saving and environmental-friendliness” in road construction.

Abstract: With the high speed railway construction in our country, the launch of the railway engineering will inevitably lead to all kinds of engineering geological problems, resulting in the construction and operation of landslides, sudden gushing mud, rock blasting and other diseases. So with geological environment and engineering geological conditions of the station tunnel excavation , analysis and evaluate the influence of the engineering geological conditions of the tunnel, put forward the measures and suggestions for the engineering, and provide the basis for tunnel design and construction .

Abstract: A steel roof structure is plum blossom-shaped and its flower core is a cable dome and five petals is a mixture structure with truss and grid. Its trusses are installed by cantilever construction. This paper analyzes the method to get pre-set deformation value (P.D.V) and makes use of software ANSYS to calculate the trusses P.D.V through backward iteration method to insure construction complete.

Abstract: Xiluodu arch dam of Xiluodu hydro-junction standing on Jinshajiang River is one of international super-hydropower-projects. Furthermore, this super arch dam lies in peculiarly complicated geographical location where the most dangerous geologies of Southern-western China live. So, the dam foundation condition must meet rigorous requirements on geological stability, mechanical-physical characters and permeability etc. Thereby, the key scientific objects include attitude of foundation surfaces, geological defects of main strata, blasting-excavation-substitution systematic construction for soft geo-layers. Based on practical survey on strata’s lithologic characters and geological structural traits from bank slopes as well as valley bed, researched comprehensively were the dam foundation weathering and unloading condition, the distribution of intra- and inter-formational disturbed belts, compressive belts and parental fissures. Particularly, discussed attentively was their quality assessment. The analyses results showed that the globally initial quality of dam foundation was super one and the local geological defects can be reinforced reliably by substitutive excavation in addition to intense consolidation grouting so as to meet constructive requirements of Xiluodu arch dam. The conclusion is the sophisticated process for blasting construction and comprehensively constructive management system is applicable. The blasting excavation produced smooth and completely split surfaces. The exposed strata’s blasting damage was controlled effectively. The geo-strata’s treatment met generally constructive safety requirements.

Abstract: The closure is just a way to build an underground wall blocking water by curtain grouting, by which in the district rich in water of mine two of Dongfeng coal mine curtain grouting was done to closure the passageway of water, reduce the water, remove the threat from water disasters, and improve the operation conditions, to promote the safety in production and increase the economic efficiency and the social efficiency; at the same time, protect the valuable water resources in periphery of mining area, maintain the balance of ecological environment, was worth to be popularized.

Abstract: Collapse accumulation is one of the most common bad geology bodies in mountain and canyon regions in southwest of China. Jiuzi collapse accumulation, which is located in the left bank of 400~1200 meters from wanjiakouzi hydropower station in the Xuanwei city Yunnan province, is primarily performing as a collapse body with some sliding character. Due to the close location to the dam site, Jiuzi collapse accumulation shows a tremendous safe hidden trouble to the engineering construction, and studying on its stabilization is of prime importance. Taking Jiuzi collapse accumulation as an example, expound the application of the Rosenblueth moment estimation method into probabilistic analysis of slope stability, effectively combined the traditional safety factor method with probability assessment method.