Open Access
ABSTRACT
PAN Yi-shan, XIAO Xiao-chun, LV Xiang-feng
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 97-98, 2011, DOI:10.3970/icces.2011.016.097
Abstract Gas slippage effects is the first time found by Kundt and Warburg, Muskat for the first time applied gas flow in porous media theory to the development of oil and gas fields, it marks gas slippage effect theoretical research possible to achieve low permeability gas reservoirs industrialized mining. In recent years, our country scholars used the theoretical analysis and experimental research methods to low permeability gas reservoirs of slippage effects, to achieve low permeability gas reservoirs industrialization mining provide a theoretical basis, as for coal-bed methane reservoir gas slippage effects study is extremely rare. So this article carries out the… More >
Open Access
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ZHANG Zhi-hui, WANG Xue-bin, PAN Yi-shan
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 99-100, 2011, DOI:10.3970/icces.2011.016.099
Abstract It is known from experimental studies that a zonal periodic structure in the form of alternated regions of fractured and relatively intact rock appears around rock workings. It is impossible to describe the occurrence of such a structure on the basis of the classical continuum model, so it attracted the research's wide attention. In order to know the crack distribution and its change along the axial direction, and this phenomenon may take place in which kinds of material, four kinds of layered similar materials blocks are used to establish a barrel model. The crack distribution and its change along the… More >
Open Access
ABSTRACT
Yishan Pan, Xiangfeng Lv, Zhonghua Li, XiChun Xiao
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 101-102, 2011, DOI:10.3970/icces.2011.016.101
Abstract Geometry size has a great influence on energy absorption ability of closed-cell foam metals. Study on energy absorption ability of closed-cell Si-Al foam metals considering geometry size by impact experiment method. The results show that the strain and absorbing energy value are decreasing with the geometry size increasing, and also lead to the hole wall rupture or whole instability. The best height-width ratio for cube and cylinder are 1.0~1.5 and 1.0~2.0, respectively. With the increasing of material diameter, the compressive strength increasing quickly, but the strain reduces. It is clearly that height-width ratio 1.0 is better for cube and cylinder. More >
Open Access
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Li Liping, Pan Yishan, Zhang Mengtao
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 103-104, 2011, DOI:10.3970/icces.2011.016.103
Abstract The block model of effect of anomalous low friction in rock mass was established based on plasticity kinetics and theoretical analysis. And the normal stress formulas of contact interface between rock stratum and roof on elastic stage and elastic-plasticity stage were presented. The theoretical analysis indicates that under dynamic loading, the normal stress of contact interface between rock stratum and roof on elastic stage and elastic-plasticity stage of simple beam both reduce, and the reduction amplitude are both great. The friction force of the contact interface reduces sharply, therefore the existence of effect of anomalous low friction in rock mass… More >
Open Access
ABSTRACT
R. Faruk Yokseler
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 105-106, 2011, DOI:10.3970/icces.2011.016.105
Abstract The mid surface of undeformed rubber-like shells undergoing finite rotations and finite strains has been considered to be the reference surface of the undeformed configuration. There have been two different definitions for the reference surface of deformed rubber-like shells, undergoing finite rotations and finite strains, used by several researchers. In this study, some comments on the stress-resultants defined relative to the mentioned two reference surfaces of deformed incompressible rubber-like shells under axisymmetrical effects, considering transverse normal and transverse shear deformations, are presented. More >
Open Access
ABSTRACT
J.P. Tang*, Y.S. Pan
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 107-108, 2011, DOI:10.3970/icces.2011.016.107
Abstract Nuclear Magnetic Resonance (NMR) as an advanced non-damaged measurement technique was introduced into the research of gas adsorption and desorption in coal to simulate physically and evaluate influence of tridimensional load and unload . Coal is typical heterogeneous material which can adsorb gas. Load and unload condition play important roles for gas storage and transport in coal. Gas in coal has two states, free and absorbed which act balance dynamically. The home-made triaxial osmoscope made up of non-magnetic polycarbonate material which has coal sample were placed into the magnetic bore of NMR spectrum equipment. The NMR spectrum experiments of coal… More >
Open Access
ABSTRACT
JIA Bao-xin, PAN Yi-shan, LI Guo-zhen
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 109-110, 2011, DOI:10.3970/icces.2011.016.109
Abstract Currently mines seismic emergence mechanism is unclear. To solve this problem, the article analyzes the occurring mechanism of mines seismic and studies the mines seismic classification. Meanwhile we establish three-Dimension excitation model of mines seismic, then derive the propagation model of mines seismic. Research shows that Coal-rock mass produced brittle fracture when outside force to exceed its ultimate strength in complex stress, after the release of energy generate mines seismic. The establishment of the model explains mines seismic occurrence mechanism, and provides the theoretical foundation for mines seismic magnitude calculation and accurate Orientation in the future. More >
Open Access
ABSTRACT
YANG Jie, SHAO Yongbo, CHEN Cheng
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 111-112, 2011, DOI:10.3970/icces.2011.016.111
Abstract A typical Y-joint is made up of a chord member and a brace member. In this structure, the brace member is usually subjected to axial load, and so the chord is always subjected to radial load which is tranferred from the brace member. As the stiffness of the chord in the radial direction is usually much smaller than that of the brace in the axial direction, failure often occurs near the weld toe on the chord surface. Increasing the thickness of the chord near the weld toe can enlarge the radial stiffness of the chord, and thus it can improve… More >
Open Access
ABSTRACT
CHEN Ying, SHAO Yongbo
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 113-114, 2011, DOI:10.3970/icces.2011.016.113
Abstract A typical square tubular Y-joint is consisted of a chord and a brace member. Due to the square hollow section, the stiffness of the chord in the radial direction is much smaller than that of the brace in axial direction, and thus failure usually occures at the weld toe in the form of local bucking. To improve the ultimate bearing capacity of the welded square tubular joints, various reinforcement measures were studied in the literature. Chord reinforcement is an available alternative which can avoid the disadvantage that it is difficult to strengthen a multi-planar tubular joint which may have sveral… More >
Open Access
ABSTRACT
Cui MingJuan, Shao YongBob
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 115-116, 2011, DOI:10.3970/icces.2011.016.115
Abstract Welded tubular structures are widely used in many constructions, such as offshore platforms, which are all consisted of welded tubular members. There is high stress concentration at the intersection between the chord and the brace. As high sress concentration exists along the weld toe, failure usually occurs in this region. To increase the bearing capacity of a tubular joint, it is necessary to take measures to reinforce the region around the weld toe. Therefore, the static strength of rectangular hollow section (RHS) T-joints with local chord reinforcement under in-plane bending load is investigated by using finite element method. To study… More >
Open Access
ABSTRACT
CHEN Cheng, SHAO Yongbo, YANG Jie
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.016.117
Abstract A group of finite element models, reinforced circular hollow section (CHS) T-joints, are established to investigate the fire resistance compared with the un-reinforced by using finite element program ABAQUS in this paper. Sequentially coupled thermal-stress analysis is used to simulate the process of tubular T-joint under different loading levels in the condition of fire. The heat properties of the steel use the specified values in Eurocode 3. The fire resistance performance of collar plate reinforce CHS T-joints and the un-reinforced models are studied under different loading levels. The applied loads are 20%, 40%, 60% and 80% of the static strength… More >
Open Access
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Qing Li Wang, Yuan Che, Yong Bo Shao, Rui Lin Li
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 119-120, 2011, DOI:10.3970/icces.2011.016.119
Abstract Based on analysis of the hysteretic experimental results of the concrete filled circular CFRP-steel tubular (C-CFRP-CFST) beam-columns, it shows that the deflection curves of all the specimens are close to half sinusoidal shape. The steel tube and the CFRP material can work concurrently both in longitudinal and transverse directions. Additionally, the longitudinal strain and the transverse strain at a same point have opposite action. Analysis indicates that there is no strength degradation. The axial compression ratio and strengthening factor of the longitudinal CFRP can enhance the strength and the stiffness of the members and they can also delay the stiffness… More >
Open Access
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Chunyu Ren, Zhihai Xiang, Zhangzhi Cen
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 121-122, 2011, DOI:10.3970/icces.2011.016.121
Abstract Recently, many interesting conceptual devices have been proposed to manipulate the propagation of acoustic waves at will. This is mostly achieved through acoustic metamaterials designed by the coordinate transformation method [1]. However, such materials are usually required to be anisotropic and inhomogeneous, which hampers their realization in practice.
In this talk, we are going to introduce conformal mapping based transformation acoustics for 2D cases [2]. In this way, the resultant metamaterial parameters are isotropic, which greatly facilitates their implementation. More >
Open Access
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Zhihai Xiang, Xiaowei Dai, Yao Zhang, Longqi Wang, Qiuhai Lu
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 123-124, 2011, DOI:10.3970/icces.2011.016.123
Abstract In this talk, we are going to introduce a new method that can detect the damage in bridge structures through the acceleration of a passing vehicle mounted with a tapping device. This method was inspired by the hunting behavior of woodpeckers and the idea of obtaining natural frequencies of bridge structures through the dynamic response of a passing vehicle [1].
Based on a simple vehicle-bridge interaction model, we analytically found out that the vehicle acceleration contains the damage information, which can be represented by the instantaneous stiffness Z as follows: (1)
where yB is the deflection of bridge,… More >
Open Access
ABSTRACT
Aiichiro Nakano, Rajiv K. Kalia, Priya Vashishta
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 125-126, 2011, DOI:10.3970/icces.2011.016.125
Abstract We have developed a metascalable (or "design once, scale on new architectures") parallelization scheme to perform large spatiotemporal-scale molecular dynamics (MD) simulations of materials on peta-to-exaflops computers based on embedded divide-and-conquer algorithms. The scheme has achieved parallel efficiency well over 0.95 on 212,992 IBM BlueGene/L processors for 218 billion-atom MD and 1.68 trillion electronic degrees-of-freedom quantum-mechanical MD in the framework of density functional theory. Simulation results reveal intricate interplay between photoexcitation, mechanics, flow, and chemical reactions at the nanoscale. Specifically, we will discuss atomistic mechanisms of: (1) mechanically enhanced reaction kinetics in nanobubbles and nanojets; (2) rapid hydrogen production from… More >
Open Access
ABSTRACT
Hsuan-Teh Hu, Jun-Ming Chen
The International Conference on Computational & Experimental Engineering and Sciences, Vol.16, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.016.127
Abstract The applications of fiber-composite laminate materials to aerospace industrial such as spacecraft, high-speed aircraft, missile and satellite have increased rapidly in recent years. The most major components of the aerospace structures are frequently made of curved panels and subjected to various kinds of compressive forces. Therefore, knowledge of the dynamic characteristics of composite laminated curved panels in compression, such as their fundamental natural frequency, is essential. The fundamental natural frequency of composite laminated curved panels highly depends on the ply orientation, end conditions, geometries (i.e., aspect ratio and curvature) and compressive force. Therefore, proper selection of appropriate lamination to maximize… More >