Applied Mechanics and Materials Vols. 170-173

Abstract: Fault fracture zone with rich water has some bad geological conditions such as low strength, deformation, strong water permeability, poor water resistance. Landslide has been happened because the water permeability. This paper is based on Yan-jia Tunnel in HuBei-Guzhu Highway. For the bad geological conditions, WSS is taken as the advanced support method to reinforce soil and stop watering. The method has improved the construction condition. To reduce the excavation area in one time and the disturbance to surrounding soil, the construction method of meshshotcreting firstly is adopted. The paper also do the numerical simulation with the numerical calculation tool of the software ABAQUS. The result is basically consistent with the field measurements, which has significance on the subsequent design and construction of underground projects with similar geological conditions

Abstract: Adopting LS-DYNA finite element simulation, the simulation model of hydraulic blasting was established. Numerical simulation of hydraulic blasting was carried out. Through the simulation, the point that the structure wall was affected by four loading functions, which include the first shock wave, bottom reflex compression wave, the compression wave of opposite wall and the bubble pulse, was put forward. The four loading functions help to extend the time span of loading, and provide basis for principle of quasi static pressure function of hydraulic blasting.

Abstract: To study the mechanical evolution rule of the supporting part in the process of the reinforced concrete chimney blasting demolition, a finite element model based on a practical project is established by explicit analysis software LS-DYNA. By means of four different Angle blasting cut finite element models, the stress distribution of the supporting part and neutral axis moving rule is drawn. It will help to develop the theory of the reinforced concrete chimneys blasting demolition.

Abstract: Cement concrete pavement joint filler construction is a weak spot. Joint filler debonding is often caused due to unnormal construction, so as to result in decreased pavement quality and reduced pavement service life. This paper describes the successful application of silicone modified polyurethane joint filler to cement concrete pavement in chilly regions, sets performance specification requirements on the filler, and improves and perfects the joint sealing construction process and later inspection technique to provide a basis for joint filler construction henceforth in chilly regions.

Abstract: Knowledge-based system (KBS) for major-pieces lifting projects can be useful for improving the level of decision-making. And it is important to use the knowledge acquired from domain experts to finish all kinds of projects for lifting major-pieces. Knowledge acquisition plays a critical role in constructing a KBS for major-pieces lifting project, also it is commonly regarded as a major obstacle and bottleneck in the process of designing and implementing a KBS. This paper presents a KBS model based on matrix representation and mapping (MRM) approach to facilitate the effectiveness of knowledge acquisition in constructing a KBS. A case study on practical application is employed to illustrate how the KBS works.

Abstract: Concrete filled steel tube is widely used in super high-rise steel structure, but there are many problem in the construction of concrete filled steel tube. With the construction of Wanxin building as an example, this paper described the selection of the construction program, and analyzed the disadvantages in construction such as the difficulties of concrete pumping and the problems of pipe blockage, pipe explosion and concrete curing during the process of construction. Based on structural characteristics and construction difficulties, the key technique of steel tube concrete construction are introduced in detail. It can provide significant reference and guide for super high-rise building construction.

Abstract: Through studying on temperature data of mass concrete poured completely after 20 days, the temperature time-history curves were plotted in different heights section of the raft foundation. Moreover, the characteristic parameters such as solid concrete temperature, temperature difference between inside and outside , also between surface and atmosphere, and its cooling rate were studied. Then by checking cracks of the mass concrete, the most likely period of temperature stress cracks appearing is pointed out. The useful experience data of the mass concrete construction in conditions of hot weather is accumulated, whose concrete strength standard is evaluated by 28d age.

Abstract: To enhance the survival capability and fast reaction capability of missile weapon system, the research on choosing launching site during the process of missile erection has been carried out. In this paper, the bearing load of launching site is analyzed in missile erecting process, and the equation of limiting bearing capacity is deduced according to K. Terzaghi suggesting equation. Combining with explicit reliability analyzing method, the sensitivity analysis of factors which influence the bearing capacity has been executed, and the detection method has been researched for partial factors which influence bearing capacity obviously. Finally, the general conceptual design of evaluating bearing capacity and choosing launching site have been provided based on blocking design thought.

Abstract: The dimensional quality of auto-body relates to the whole external appearance and wind noise, the effect of closing the door and even driving smoothness of vehicles. The deviation propagation can be analyzed through the method of influence coefficient (MIC). However, fixture deviation usually impacts on the assembly variation than part variation. A variation analysis modeling with fixture configuration is presented to improve the current variation analysis efficiency of sheet metal parts. The variation change process of part, fixture and assembly was analyzed by researching the locating and assembly process of sheet metal parts. The linear relationships among variations of parts, fixtures and assemblies are established with two locating principles of “N-2-1” and “3-2-1”. Moreover, in accordance with the different release modes of the fixture locating points after the assembly, the assembly variation modeling is established in the two modes of over-constrained release and full release. Finally, a case of sheet metal assembly is illustrated to show the effectiveness of the assembly variation analysis modeling.

Abstract: In Linux embedded system, multimedia application is becoming more and more popular based on the ARM process, therefore, it is very urgent that the development of audio and video in one multi-functional player. Using audio and video media library function, IIS interface, DMA control technology and LCD display technology, to development multimedia player function, using Qt complete embedded graphical user interface development so that the system has a good interface. The audio and video data Input/output by the study, using the software decoding, reduces the system development cost, solve the media play the normal player function. The design principle is clear, easy to realize, has a certain practical value.