Jorge Daniel Riera¹, Letícia Fleck Fadel Miguel², Ignacio Iturrioz³

CMES-Computer Modeling in Engineering & Sciences, Vol.82, No.2, pp. 113-136, 2011, DOI:10.32604/cmes.2011.082.113

Abstract In the truss-like Discrete Element Method (DEM), masses are considered lumped at nodal points and interconnected by means of uni-dimensional elements with arbitrary constitutive relations. In previous studies of the tensile fracture behavior of concrete cubic samples, it was verified that numerical predictions of fracture of non-homogeneous materials using DEM models are feasible and yield results that are consistent with the experimental evidence so far available. Applications that demand the use of large elements, in which extensive cracking within the elements of the model may be expected, require the consideration of the increase with size… More >

T.M. Hatem¹, M.A. Zikry¹

CMC-Computers, Materials & Continua, Vol.17, No.2, pp. 127-148, 2010, DOI:10.3970/cmc.2010.017.127

Abstract A three-dimensional multiple-slip dislocation-density-based crystalline formulation, and specialized finite-element formulations were used to investigate dislocation-density evolution and crack behavior in single-packet lath martensite in high strength martensitic steels. The formulation is based on accounting for variant morphologies and orientations, and initial dislocations-densities that are uniquely inherent to martensitic microstructures. The effects of loading plane with respect to the orientation o the habit plane are investigated. Furthermore, the formulation was used to investigate single-packet microstructure mapped directly from SEM/EBSD images of maraging and ausformed martensitic steel alloys. This analysis underscores that shear pipe effects in martensitic More >

A. Rama Chandra Murthy¹, G.S. Palani¹, Nagesh R. Iyer¹

Structural Durability & Health Monitoring, Vol.5, No.3, pp. 201-226, 2009, DOI:10.3970/sdhm.2009.005.201

Abstract This paper presents methodologies for residual strength evaluation of metallic structural components under fatigue loading. Structural components include plate panels of different crack configurations with and without stiffeners. For stiffened panels, stress intensity factor (SIF) has been computed by using parametric equations based on numerically integrated modified virtual crack closure integral (NI-MVCCI) technique. As a part of residual strength evaluation, remaining life has also been predicted by using standard crack growth models. Various methodologies for residual strength evaluation, namely, plastic collapse condition, fracture toughness criterion and remaining life approach have been described. From the studies, More >

Yong-bin Park¹, Jin-Hwe Kweon¹, Jin-Ho Choi¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.2, pp. 39-40, 2009, DOI:10.3970/icces.2009.012.039

Abstract This paper addresses experimental results on the strength of single-lap composite bonded joints with different manufacturing methods and configurations. The joints were fabricated with 4 different methods; Co-curing with additional adhesive (CCA) and without additional adhesive (CCN) between composite adherends, Co-bonding (COB) and secondary bonding (SEB). Joints have 5 different overlap lengths(l), 3 different lay-up patterns and 4 different thicknesses(t), respectively. Width of the joints(w) is constant at 25.4 mm. A total of 389 single-lap specimens were tested in tension. In the test to examine the effect of manufacturing methods and overlap lengths, the joint… More >

Eun A Hwang¹, Haeng-Ki Lee¹, Jong Won Kwark², Jung Woo Lee²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.12, No.1, pp. 11-12, 2009, DOI:10.3970/icces.2009.012.011

Abstract Concrete structures such as concrete safety barriers are often subjected to direct impact loads mainly due to vehicle crash impact. In this case, the impact resistance is one of the most critical characteristic of concrete used in such structures. The present study aims to characterize the impact resistance of lightweight aggregate cellular concrete (LACC), which will be used in concrete barriers. Impact tests on LACC specimens were carried out based on the repeated drop-weight impact test guideline recommend by ACI committee 544. Impact resistance and compressive strength of the LACC specimens were characterized and the More >

Hisham Abdel-Fattah¹, Sameer Hamoush²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.11, No.4, pp. 111-112, 2009, DOI:10.3970/icces.2009.011.111

Abstract This paper develops Fiber Reinforced Plastic (FRP) Composites retrofit systems to enhance the structural performance of deficient reinforced concrete beams. The paper highlights the design of the different FRP systems and then, systems with promising results are used to upgrade deficient beams. Structural evaluation for retrofitted beams is performed to evaluate the ductility and strength performance. This study mainly focuses on the uses of Glass Fiber Reinforced Plastics (GFRP), Carbon Fiber Reinforced Plastics (CFRP) and hybrid reinforced plastics that use a mixture of carbon and glass fibers. As part of the design of the FRP… More >

P. Kolarkar¹, M. Mahendran, S. Gunalan

The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.4, pp. 243-244, 2009, DOI:10.3970/icces.2009.009.243

Abstract Fire safety of light gauge cold-formed steel frame (LSF) stud wall systems is critical to the building design as their use has become increasingly popular in commercial, industrial and residential construction throughout Australia. These walls are made of a cold-formed steel frame lined with multiple plasterboards (up to 4 on each side) and are often used as load-bearing walls. Currently there is limited design information on LSF load bearing walls for use by Australian engineers and designers. Hence LSF wall manufacturers depend on full scale fire tests using the standard fire curve based on ISO834… More >

H. T. Wang¹, Z. H. Yao²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.9, No.2, pp. 95-96, 2009, DOI:10.3970/icces.2009.009.095

Abstract Carbon nanotubes (CNTs) may provide ultimate enhancement in stiffness and str\discretionary {-}{}{}ength for composite materials. This paper presents a rigid-fiber-based boundary integral equation formulation for the numerical simulation of debonding process and the corresponding strength of CNT reinforced composites. The CNT/matrix interfaces are assumed to fail when the interfacial shear force reaches a prescribed threshold, and the CNTs and matrix are considered to be detached in the failed areas. The matrix with one or several tens of originally well-bonded CNTs is subjected to an incremental tensile load and the effective stress-strain relations are readily obtained… More >

A.Oba¹, Y.Fujii², M.Okuma³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.1, pp. 51-56, 2008, DOI:10.3970/icces.2008.007.051

Abstract In this paper, the authors present a new evolutionary structural optimization method based on FE modeling using identical cubic elements for optimizing strength and dynamics characteristics of structures. The method is developed from the previous ones([1\hbox {}]-[3\hbox {}]), and carries out the size and topological shape optimization to satify the strength against external force and inertia force of itself and to control the natural frequencies of the structure. The method gives us the lightest structure satisfying the requirement about the strength and dynamic characteristics. The outline of the method is presented first, and a basic More >

Roberta Apostolska¹, Golubka Necevska-Cvetanovska²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.5, No.2, pp. 129-136, 2008, DOI:10.3970/icces.2008.005.129

Abstract The IZIIS' contribution to development of high quality materials has been seen in realization of several scientific-research projects in the field of high strength concrete in the period from 1992 to 2006. Within the frames of these projects complex laboratory-experimental-analytical investigations have been performed to contribute to definition of the methodology for obtaining high stength concrete exclusively from domestic resources, to investigate joint behaviour of high strength materials and elements in nonlinear range as well as to define dynamic behaviour high strength concrete buildings exposed to seismic actions. The selected results from these investigations are More >