V. Mallardo^1,2, M.H. Aliabadi³

Structural Durability & Health Monitoring, Vol.9, No.4, pp. 287-323, 2013, DOI:10.32604/sdhm.2013.009.287

Abstract The optimum location of the sensors is a critical issue of any successful Structural Health Monitoring System. Sensor optimization problems encompass mainly three areas of interest: system identification, damage identification and impact identification. The current paper is intended as a review of the state of the art at the year 2012 and going back to 1990. The above topics have been dealt with in separate contexts so far but they contain interesting common elements to be exploited. More >

D. Schleh¹, D. Liu¹

Structural Durability & Health Monitoring, Vol.9, No.3, pp. 201-216, 2013, DOI:10.32604/sdhm.2013.009.201

Abstract Understanding the response of composite materials to dynamic loading is necessary for their safe and efficient application to many of the world’s engineering designs where stiffness-to-weight ratios are vitally important. In this study, fringe projection was used and evaluated as means to measure the out-of-plane displacement of composite materials from impact loading involving a projectile accelerated horizontally through the use of gas. The capability of providing out-ofplane deformation measurements can largely enrich the investigation of composite materials under horizontal impact which are commonly performed without any measurement other than projectile velocity. The out-of-plane displacement history More >

Smitha Gopinath^1,2, A. Ramachandra Murthy¹, Nagesh R. Iyer¹

Structural Durability & Health Monitoring, Vol.9, No.1, pp. 1-20, 2013, DOI:10.32604/sdhm.2013.009.001

Abstract This paper deals with the performance of concrete specimens confined with different glass fabric reinforcement in organic binder consisting of resins. Three varieties of glass fabrics such as woven roving (WR), chopped strand mat (CSM), and textile reinforcement have been studied in the investigation. Experiments have been conducted on unconfined and confined concrete cylindrical specimens under compression. The effect of number of layers on confinement has been studied for specific cases. Specimens have been tested under displacement control. It is observed from the experiments that there is an increase in load carrying capacity as well More >

Smitha Gopinath^1,2, J. Rajasankar¹, Nagesh R.Iyer¹, A.Rama Chandra Murthy¹

CMC-Computers, Materials & Continua, Vol.33, No.1, pp. 87-110, 2013, DOI:10.3970/cmc.2013.033.087

Abstract An integrated model is proposed to describe tension stiffening in reinforced concrete (RC) flexural members that are undergoing uniform corrosion of reinforcement. The tension stiffening model is taken as base to incorporate the effects of reinforcement corrosion. The model is developed in two steps. In the first step, tension stiffening of concrete is modelled using an exponential stress-strain curve defined as function of a decay parameter. Modular ratio and reinforcement ratio are considered in the definition of the decay parameter. In the second step, the effects of uniform corrosion of reinforcement are integrated with the… More >

Changqing Miao¹, Yintao Wei², Xiangqiao Yan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.6, pp. 519-534, 2013, DOI:10.3970/cmes.2013.095.519

Abstract By using a hybrid displacement discontinuity method, the interactions of three parallel square-hole cracks in an infinite plate subjected to internal pressure are investigated in this paper. Numerical examples are included to illustrate that the numerical approach is very simple and effective for calculating the stress intensity factors (SIFs) of complex plane crack problems. Many numerical results of the SIFs are given and discussed. It is found that a square hole has a shielding effect on crack(s) emanating from the hole. The finding perhaps has an important meaning in engineering. More >

Changqing Miao¹, Yintao Wei², Xiangqiao Yan¹

CMES-Computer Modeling in Engineering & Sciences, Vol.94, No.1, pp. 29-52, 2013, DOI:10.3970/cmes.2013.094.029

Abstract This paper is concerned with periodic collinear circular-hole cracks in an infinite plate in tension. A numerical approach to this type of circular-hole cracks is presented. Numerical examples are included to illustrate the accuracy of the numerical approach. By means of a generalization of Bueckner's principle and by using a displacement discontinuity method, periodic collinear circular-hole cracks in an infinite plate in tension are investigated in detail by using the numerical approach. Many numerical results are given and discussed. More >

Q. G. Liu¹, B. Šarler^1,2,3,4

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.4, pp. 235-266, 2013, DOI:10.3970/cmes.2013.091.235

Abstract The purpose of the present paper is development of a Non-singular Method of Fundamental Solutions (NMFS) for two-dimensional isotropic linear elasticity problems. The NMFS is based on the classical Method of Fundamental Solutions (MFS) with regularization of the singularities. This is achieved by replacement of the concentrated point sources by distributed sources over circular discs around the singularity, as originally suggested by [Liu (2010)] for potential problems. The Kelvin’s fundamental solution is employed in collocation of the governing plane strain force balance equations. In case of the displacement boundary conditions, the values of distributed sources… More >

Jian Hua Rong^1,2,3, Zhi Jun Zhao⁴, Yi Min Xie⁵, Ji Jun Yi^1,2

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.3, pp. 211-231, 2013, DOI:10.3970/cmes.2013.090.211

Abstract Similar periodic structures have been widely used in engineering. In order to obtaining the optimal similar periodic structures, a topology optimization method of similar periodic structures with multiple displacement constraints is proposed in this paper. Firstly, in the proposed method, the design domain is divided into sub-domains. Secondly, a penalty term considering discrete conditions of density variables is introduced into the objective function, and the reciprocal density exponents of structural elements are taken as design variables. A topological optimization model of a similar periodic continuum structure with the objective function being the structural mass and More >

Zonglu Guo¹, Deli Gao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.90, No.1, pp. 65-76, 2013, DOI:10.3970/cmes.2013.090.065

Abstract The modeling of the bottomhole assembly (BHA) is an essential problem in directional drilling. Some basic equations for predicting the performance of the BHA are presented in this paper. These equations take into account the effects of the axial displacement. The method of weighted residuals and the Newton-Raphson iterations are used to compute the nonlinear effects of the deformation of the BHA. A computer program is developed for the analysis of the BHA in order to quantitatively predict the performance of the BHA in directional drilling. In addition, a case study is presented to evaluate More >

D. Bergmair^1,2, S. J. Metz¹, H. C. de Lange², A. A. van Steenhoven²

CMES-Computer Modeling in Engineering & Sciences, Vol.91, No.1, pp. 1-15, 2013, DOI:10.3970/cmes.2013.091.001

Abstract A method to predict the permeation of water vapor, present in a laminar flowing humid carrier gas, through a hollow fiber membrane is presented. The method uses simulation particles that move like molecules, according to the kinetic gas theory, but carry the physical properties of an ensemble of molecules which they statistically represent. With this approach an ideal operational window for membrane modules can be found and parameters tested for, can be varied over orders of magnitude. The results show that the right dimensioning is essential for the efficient use of the membrane area. More >