Advanced Materials Research Vols. 250-253

Abstract: Maximum local thermal effects carpet plots for symmetric laminated composite plates used in the design and optimization for material under heat loads are produced and demonstrated. The independent variables considered in this paper are the proportions of 0, 45, and 90 degrees ply orientations in the laminates. The carpet plots are presented in such a way that when the failure stress or strain of a composite lamina is known, all possible safe ply orientation proportion can be determined. In addition, the dependency of the carpet plots in correspondence to the temperature change is investigated. It is found that the shapes of both thermal stress and strain plots are practically identical.

Abstract: The aim of this paper is to introduce a virtual crack closure technique based on EFG method for thread-shape crack. The cracked component is discretized and the displacement field is determined using a coupled FE/EFG method, by which EFG nodes are arranged in the vicinity of crack tip and FE elements in the remain part in order to improve computational efficiency. Two typical parameters, nodal force and crack opening displacement attached to crack tip are calculated by means of setting up an auxiliary FE zone around crack tip. Strain energy release rate (SERR), further stress intensity factor (SIF) are determined by the two parameters. The method to calculate SIF is named as virtual crack closure technique based on EFG method. It is showed by several numerical examples that using the method presented in this paper, SIF on the crack tip can be obtained accurately.

Abstract: The California Bearing Ratio(CBR) denotes the potential strength of subgrade material and is the important index of evaluating its using performance in expressway. In order to study the main influence factors of the CBR value of clay, The physics and chemistry tests of fifteen groups subgrade materials, coming from the Qing(Dao)-Yin(Chuan) expressway in hebei province, are done. Based on the result of tests, which there are obvious difference between CBR value with the same plastic index clay under the same test method and condition, the influence factors of California Bearing Ratio of expressway subgrade materials are distribution of particle sizes in soils, mineral component and clay mineral component. The profitable conclusions are gained: the main influence factors of California Bearing Ratio of expressway subgrade material are the type of mineral component and the content of each mineral, the distribution curve shape of particle sizes in soils and the clay ratio silt secondly. The CBR value minishs with the clay ratio silt increasing.

Abstract: Explosive specific charge is the key to the high level of casting blast. In order to study how the explosive specific charge affects the high bench cast blasting, theoretical analysis and experimental study were used in the Hei Dai-gou open pit cast blasting. Experimental study shows that: under the same engineering geological conditions and blasting parameters, the throw distance increases as the average explosives specific charge increases, and this trend slows down gradually. Settlement muck-pile height increases as explosives specific charge increases, and then gently muck-pile shape tends to be more conducive to the work platform dragline flat-field and inverted reactor efficiency. When q> 0.65 kg/m³, the cast percentage can reach more than 30%, as 0.67 kg/m³ <q <0.70 kg/m³, the cast percentage increases with a significant effect as the explosives specific charge increases; when q> 0.74 kg/m³, the increasing rate of the cast percentage with the increase of explosive specific charge decreases.

Abstract: This paper presents the flood inundation model using a hydrodynamic approach for flood simulation. A Digital Elevation Model (DEM) for Damansara Catchment was developed and integrated into the InfoWorks River Simulation (RS) program. Hydrographic surveying activity was carried out to collect existing Damansara River cross-section. The 3D flood model was calibrated using the 26^th February 2006 and 15^th October 2008 flooding event data. The model was validated using the flooding event on 21^st March 2007. This computer simulation results produced hydrograph that indicates the capability of the model in dealing with regional flood analysis for future usage in designing structural flood measures.

Abstract: Analyzing the nitrate seasonal distribution and nitrate high-value areas in Kuroshio of East China Sea, shows that: (1) The average concentration of nitrate in Kuroshio of East China Sea were the highest in summer and the lowest in winter, the continental shelf area was higher than the off the coast area and nitrate concentration increased with depth. (2) There were three major high-value areas of nitrate in Kuroshio of East China Sea. The first high-value area’s center was 122.5°E, 26.5°N in northeast of Taiwan island, the depth range was 0~100m. The second high-value area distributed around 124.5°~126.2°E, 25°~ 27°N, the depth range was 100~500m. The third was in southwest of Kyushu which was in north of 28.5°N, the depth range was 0~500m. These areas were potentially highly productive areas, and also were the fish resource rich areas which needed to pay more attention on exploration in Kuroshio of East China Sea in future.

Abstract: Firstly, this paper gives a brief review of the nature and characteristics of sustainable and healthy residence. Secondly, with an analysis to the current situation and problems of urban residence in China, it makes a tentative study on the development trend of healthy residence based on the concepts of opening urban space and new auto culture. Finally, it initiates some proposals for healthy residence with energy-saving and environmental protection.

Abstract: Measuring system of soil moisture and water bedload LGD-Ⅲ was used in those tests . Infiltration law of one dimensional vertical soil poles were carried out profound studies,under different density and a constant water head . At the same time,the course of wetness front along with time pass away, infiltration law along with time pass away and different high water content along with time pass away were made a comprehensive studies , under different dry density. According to a great deal of test data, the relationship between wetness front and time was given to a function under different dry density.

Abstract: It is clear from the former researches on reinforced concrete filled tubular steel (RCFT) structures that RCFT structures have better performance than concrete filled tubular steel (CFT) structures, in other words, because of the existence of reinforcement, the performance of RCFT differed from that of CFT. Therefore, to clarify the effect of axial reinforcement on mechanical properties of RCFT, compression tests of RCFT columns with different ratio of axial reinforcement were carried out, meanwhile, corresponding tests of CFT, reinforced concrete (RC), pure concrete, and steel tube columns were done to compare with RCFT. By a series of comparison and analysis, effect of axial reinforcement on RCFT columns were discussed, and following conclusions were drawn: reinforcement ratio has direct effect on performance of RCFT. Over arranged reinforcement will cause pre-failure of concrete without exerting strength of reinforcement, and not only may cause brittle-failure or lower performance of the structure, but also cause the increase of construction cost. On the contrary, proper ratio of reinforcement can make the RCFT possess better confined effect, improve overall performance of the RCFT structure; furthermore, whatever the ratio of reinforcement, RCFT has better performance than both CFT and RC, especially possesses more brittle-failure resistance than CFT.

Abstract: Along with the improvement of dwelling quality, the length of time and frequency of outdoor activities in winter greatly increase in the north China area, although the outdoor thermal environments are still unsatisfactory. It is necessary for both planners and architects to improve outdoor thermal environments in the cold regions of north China. This paper firstly introduces the general winter climate features in some north China cities. Then, it takes Xi'an city as an example to show the shortage of uncomfortable outdoor environment. Thirdly, the design strategies to improve outdoors thermal comfort include wind and snow protection, sunlight usage, environmental zones and recreational facilities, etc. are discussed.