Hanxing Zhu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 131-132, 2011, DOI:10.3970/icces.2011.017.131

Abstract This paper aims to study the size-dependent elastic properties of micro- and nano-sized open-celled foams. To simplify the analysis, we use perfect regular body-centered cubic structure (i.e. BCC foam), which has cubic symmetry and only three independent elastic constants. Taking strut bending, twisting and axial compression/stretching as the deformation mechanisms, Zhu, Knott and Mills (JMPS, V45, pp. 319-343, 1997) have obtained closed form results of all the three independent elastic constants (i.e. the Young's modulus E11 , the shear modulus G12 and the Poisson ratio v12 ) as functions of the bending stiffness, the torsional stiffness and the compression/stretching stiffness… More >

Xiuqing Qian, Yanping Cao, Kunya Zhang, Zhicheng Liu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 129-130, 2011, DOI:10.3970/icces.2011.017.129

Abstract Depth-sensing instrumented indentation tests are widely used to probe the mechanical properties of materials at a local area and small scales. Generally, indented solid was assumed semi-infinite plane solid because the contact region is small comparing the indented solid. However, for some biomaterial, such as skin, cornea and sclera, the effect of the curvature of the surface cannot be ignored. Using systematic finite element analysis and dimensional analysis, a method to determine the elastic modulus of the materials with curved surface is proposed using flat punch indentation in this paper.

An axisymmetric, two-dimensional model was adopted and four-node bilinear… More >

Wei LIU, Jiacong YIN, Pu CHEN, Xianyue SU

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 127-128, 2011, DOI:10.3970/icces.2011.017.127

Abstract In this paper, parametric modeling technique is employed to fast build the three-dimensional finite element shell model of a preliminarily designed large composite wind turbine blade, which is subsequently used in the dynamic analysis and static elastic aeroelastic stability analysis of the blade. In the dynamic analysis, natural frequencies and corresponding modal shapes are obtained for the blade in the case of being still as well as being rotating with rated revolution. For the rotating blade, the stress stiffening effect and spin-softening effect due to the centrifugal forces are taken into account. The static elastic aeroelastic stability analysis, i.e. buckling… More >

Zhongbin Zhou, Pengwan Chen, Fenglei Huang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 125-126, 2011, DOI:10.3970/icces.2011.017.125

Abstract The macroscopic deformation and fracture behavior of a polymer bonded explosive (PBX) simulation material were studied by using Digital Image Correlation (DIC) method. The Brazilian test, semi-circular bending test, punch loading and uniaxial loading experiments were chosen for the study. The whole displacement and strain fields were obtained by using DIC method at macro-scale. New sights into fracture processes and failure mechanisms of simulant samples under different quasi-static loading conditions have been obtained. Macro studies show that the experimental results are in agreement with the theoretical analysis. The experimental methods combined with DIC technique have broad applicability to deformation and… More >

Richard L.Martin

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 123-124, 2011, DOI:10.3970/icces.2011.017.123

Abstract The electronic structure of many of the oxides containing d- and f-elements has long been a challenge for theory. For example, the traditional workhorses of density functional theory, the local density approximation (LDA) and the generalized gradient approximations (GGA), predict most of these systems to be metallic, when in fact they are insulators with band gaps of several eV. These problems reflect the localization/delocalization dilemma faced in systems with weak overlap and seem to be largely overcome by the new generation of hybrid density functionals developed for molecular studies. Only recently has it been possible to apply these functionals to… More >

Xiuqin Zhang¹, Simon Wang^2*, Yingshun Zhang³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 121-122, 2011, DOI:10.3970/icces.2011.017.121

Abstract A B-spline finite strip model is developed in the context of a layer-wise plate theory for analysing the geometrically non-linear transient response of laminated composite plates subjected to transverse low-velocity impact. To simplify the complicated contact analysis, a Hertz-type contact law has been incorporated into the finite strip (FS) model for accounting for the contact behaviour. The model includes the geometrical non-linearity through use of von Karman's non-linear strain-displacement relationship. The resulting non-linear dynamic problem is solved using the Newmark time-stepping scheme together with Newton-Raphson iteration. Several numerical applications are described and a close comparison is found between the results… More >

Jianyong Huang, Xiaoling Peng, Chunyang Xiong, Jing Fang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 119-120, 2011, DOI:10.3970/icces.2011.017.119

Abstract Cell-substrate interfacial interplay plays a key role in many fundamental aspects of mammalian physiology. Recent progresses in related experiments concerning cell interactions with extracellular matrix have demonstrated that substrate rigidities can exert a remarkable influence on cell adhesion and spreading dynamics. For example, it has been reported that cell-substrate adhesion strength usually rises monotonically with Young's modulus of underlying elastic substrates and eventually achieves the strongest adhesion on rigid substrates such as glass, and that cell spreading area takes on a growing trend with the increase in substrate hardness and finally reaches a plateau when the stiffness exceeds the order… More >

Shang Yang, Sun Xiangyi, Yang Xia, Wang Xi, Yu Qifeng

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 117-118, 2011, DOI:10.3970/icces.2011.017.117

Abstract A new method of camera calibration is presented for exact videometrics in large field. The camera to be calibrated and the control points used in the new method are both close to the ground. In the condition that the control points and the camera are approximately coplanar, the main point position, focus length, lens distortion coefficients and the camera's position and attitude parameters are calibrated precisely by the method. Two calibration images are taken by the camera to be calibrated in measurement state and vertical rotation state respectively. If the vertical tangent lens distortion can be neglected or the movement… More >

Guo Baoqiao, Chen Pengwan, Zhang Qingming, Li Yanjie, Xie Huimin

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 115-116, 2011, DOI:10.3970/icces.2011.017.115

Abstract Optical full-field measurement methods are now widely applied in various domains. In general, the displacement fields can be directly obtained from the measurement; however in mechanical analysis strain fields are preferred. To extract strain fields from noisy displacement fields is always a challenging topic. In this study, a finite element method for smoothing displacement fields and calculating strain fields is proposed. An experimental test case on a holed aluminum specimen under tension is applied to validate this method. The heterogeneous displacement fields of the area around the hole are measured by the digital image correlation (DIC). By our proposed method,… More >

Zhao Zilong, Ma Shaopeng, Wang Xian

The International Conference on Computational & Experimental Engineering and Sciences, Vol.17, No.4, pp. 113-114, 2011, DOI:10.3970/icces.2011.017.113

Abstract As one of the most important photomechanics experimental methods, digital image correlation (DIC) has been widely used in various areas for displacement and deformation field measurement. The main idea of DIC is to resolve the displacement of speckle patterns by independently matching the corresponding patterns on reference and deformed speckle images. In order to add the continuity between the matching of the adjacent patterns, the mesh based DIC (abbreviated mesh-DIC hereafter), in which the whole image are matched, is proposed by Sun, et al. In mesh-DIC, the whole displacement field is characterized by a mesh which is constructed by 4-node… More >