Applied Mechanics and Materials Vols. 353-356

Abstract: In this paper, the consolidation settlement and settlement rate were studied based on the drilling data of the Yellow River subaqueous delta. The results show that surface sediments of ZK-2 are significantly coarsen than ZK-1, and correspondingly with varying physical and mechanical properties in different cores. Based on the one-dimensional consolidation theory, 50m thickness of layer could produce a total of 1.70m settlement in ZK-1, and 60m could produce 2.34m settlement in ZK-2. The consolidation settlement of unit depth is at 0.1~9cm/m. The consolidation degree needs about 15~20 years to reach 90% and the average sedimentation rate is at 7-9cm/a.

Abstract: Cohesive soil containing calcareous nodule in Huaibei plain is a kind of regional special soil, which has a unique material composition and structure. The paper discusses the types and distribution of calcareous concretion in soil, and the influence on the strength of soil and the engineering property. Through a lot of the load test and the corresponding static cone penetration test, analyzing the correlation between them.Then linear regression equation between and is established. Finally, it is show that linear regression effect is remarkable, and the equation can be reference for the local practical engineering

Abstract: Abundant landslides were triggered by Wenchuan earthquake. The paper mapped 4722 earthquake-induced landslides and used Geographic Information System to finish the statistical data about the occurrence of landslides correlating with environmental factors including distance from middle faults, lithology, altitude, river, and slope steepness. Because the seismic energy released along the middle faults and the attenuation of energy was obvious in minor axis, the zonal distribution of landslides was consistent with strike of middle faults and about 64.42% of landslides occurred within 20 km from middle faults of Longmenshan. As the middle faults and front faults both belonged to thrust faults, the impact of earthquake in hanging wall was higher than that in footwall. Therefore, the density of landslide in hanging wall of middle faults was obviously higher than that in footwall. As the release of seismic energy was restricted by landform and river, landslides were concentrative and consistent with the spatial distribution of rivers in the mountainous terrain. The scale effect of seismic acceleration was so intense in top of mountain with high difference in elevation along river that the origin of most landslides were in upside of slope. About 99.43% of landslides distributed in area where the seismic intensity was more than VII.

Abstract: The CH₄-CO₂ replacement method to recover CH₄ from hydrate-bearing sediments has received great attention because it enables the long term storage of CO₂ and is expected to maintain the stability of gas hydrate-bearing sediments. This paper extends our previous study of the stability of CH₄ hydrate-bearing sediments to CO₂ hydrate-bearing sediments to evaluate the safety of the CH₄-CO₂ replacement method. Low temperature, high pressure triaxial compression apparatus was used to measure the mechanical properties of CO₂ hydrate-bearing sediments. The triaxial tests results for CH₄ and CO₂ hydrate-bearing sediments were then compared. It was found that the failure mode of both the CO₂ and CH₄ hydrate-bearing sediments was a bulging deformation at mid-height on the samples. Moreover, the stress-strain curves of both the CO₂ and CH₄ hydrate-bearing sediments appear to be hyperbolic in shape, and could be divided into three stages: the quasi-elastic stage, the hardening stage and the yield stage. However, the strength of the CO₂ hydrate-bearing sediments was approximately 15% larger than that of the CH₄ hydrate-bearing sediments under the same conditions. The results imply that the stability of gas hydrate-bearing sediments could be maintained using the CH₄-CO₂ replacement method to recover CH₄ from these sediments.

Abstract: The measurement robot (TCA2003 Total Station) has been adopted to solve the problems of landslides emergency monitoring. The working principle and characteristics of measurement robot were briefly introduced. Then a main frame of the deformation monitoring system based on measurement robot was presented and the corresponding software was designed. Based on the GPS deformation monitoring system, the measurement robot automatic emergency monitoring system were established. The application of measurement robot in deformation monitoring system for landslides of the Three Gorges was mainly studied in this paper. The method of monitor landslide by the robot deformation monitoring system has several advantages and extensive application foreground.

Abstract: The mineralization of collision orogeny is an important part of continental dynamics. For the process of continental dynamics of Shandong, adoption of tectonic facies mapping is main carrier and specific expression form to these researches such as divergence of continental mass, convergence, collision and orogeny. Shandong tectonic facies mapping of 1:500000 scale worked out by author shows that there are two very important events of collision orogeny in Mesozoic this areaIndochina and Yanshan collision orogeny. The Indochina orogeny is mainly characterized as subduction from Yangtze to North China Plates, based on which Sulu high-ultra high pressure zone of metamorphism, syn-orogenic granite and post-orogenic high alkali sinaite are formed. Continental dynamics environment of the Yanshan orogeny derives from transformation from Central Asia-Tethys tectonic domain to marginal-Pacific tectonic domain and subduction of Pacific plates, and it appears as three orogenys and three stretching in the east of Shandong. Magmatic rocks of orogeny related with gold ores can be divided into four combinations as follows: Linglong gneissic granite of the early orogenic period (J₃), Guojialing granodiorite-granite of the middle orogenic period (K₁), Weideshan diorite-granodiorite-granite of the late orogenic period (K₁) and A-type Laoshan geode parlkaline alkali granitesyenogranite of the post orogenic period. For combination of Guojialing granodiorite-granite of the middle orogenic period, SHRIMP U-Pb ages concentrate in 130~126Ma, which are closely related with emplacement of gold ores, and formed ages of gold ores this area concentrate in 115~120Ma, which basically stand for the age of main mineralization period. Polymetallic ores are related with combination of Weideshan diorite-granodiorite-granite of the late orogenic period, and it was also the superimposed mineralization period in the east of Shandong. Tectonics-magma activities and gold ores mineralization are controlled by interaction of three tectonic domains that are tethys, Paleo-Asian Ocean and Pacific. Dynamics background of gold ores this area is transition of tectonic system and lithospheric thinning in Mesozoic, which is related with collision of North China and Yangtze Plates and subduction of Pacific Plates.

Abstract: This paper presents a three dimensional simulation method by modeling on the basis of fluid dynamics and soil mechanics. The programed calculation model is suitable for the simulation of landside that present viscous movement features. Based on the tested parameters by shear tests, the movement of a typical loess landslide was simulated and its spatial range was predicted. The results showed that the loess landslide will lead to a great damage to the local historical sites as well as the densely populated city.

Abstract: It is generally considered within analysis the residual stresses that unloading occurs on elastic law. For large initial loads, some plasticity theories believe that during unloading secondary plastic deformation can occur. The distinctive work provides a new theorem of unloading, which takes into account irreversible changes in the mechanical characteristics of the material under load. There is an example of the analysis of residual stresses corresponding to the given theorem.

Abstract: Middle route of South-to-North Water Transfer Project of Yuzhou section of the mined-out area of coal mining area is old, has the characteristics of small coal mine of irregular, no mine distribution, engineering geological conditions are very complicated, decided to adopt the filling grouting treatment after analysis. Because the goaf filling grouting treatment scope, size, slurry material costs become an important factor restricting the engineering project management, and setting strength and fineness requirements of grouting material is relatively low, overall consideration the mined-out geology topography and distribution characteristics, combines with the highway, railway and other treatment of research results of mined-out area, comes up with the cement grout high containing 85% fly ash filling grouting, and provides valuable experience for similar goaf.

Abstract: Based on the basic principle of the efficacy coefficient method, a model of rockburst intensity prediction was established. Considering the key affecting factors of rockburst, three factors were selected as evaluation indexes including the ratio of maximum tangential stress and rock uniaxial compressive strength, the ratio of compressive and tensile strength of rock and elastic energy index. Finally, the model was applied to the rockburst prediction of water diversion tunnel of Jiangbian hydropower station and the results show that the method is reliable, and it provids a new idea to predict rockburst.