Zhao Xilong¹, Zhang Jianxun¹, Chen Hongyuan^1,2, Song Xu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.6, pp. 557-571, 2013, DOI:10.3970/cmes.2013.092.557

Abstract In order to study failure perspective of Ti-6Al-4V titanium alloy welded joint, fracture behavior of the heat affected zone is researched. Microhardness, tensile test and microstructure are used to study the mechanical properties of the titanium alloy laser welded joint. The tensile and microhardness results show that heat affected zone near the base metal is the weakest in welded joints. This paper is based on the results from in-situ tension test to observe the process of crack expansion in heat affected zone. And then, in-situ test is simulated via the finite element method on ABAQUS More >

Smitha Gopinath¹, C.K. Madheswaran¹, A. Rama Ch,ra Murthy¹, Nagesh. R. Iyer², Barkavi.T³

CMES-Computer Modeling in Engineering & Sciences, Vol.92, No.2, pp. 151-172, 2013, DOI:10.3970/cmes.2013.092.151

Abstract This paper presents the details of experimental and numerical investigations performed on fabric reinforced concrete (FABcrete) panels under impact loading. Experimental investigations have been carried out using drop weight impact on a square FABcrete panel to study the damage, failure mode and acceleration. The drop weight of 20 kg is used for the study and drop heights have been varied as 100mm, 200mm and 300mm. Numerical simulation of the drop weight impact tests on FABcrete panels have been carried out and observed that there is a good correlation between experimental and numerical predictions. It is More >

M. C. Song¹, B.V. Sankar¹, G. Subhash¹, C. F. Yen²

CMC-Computers, Materials & Continua, Vol.35, No.1, pp. 67-85, 2013, DOI:10.3970/cmc.2013.035.067

Abstract Delamination initiation and propagation in plain woven laminates and 3D orthogonal woven composites during short beam shear (SBS) test were analyzed using finite element (FE) analyses. Two kinds of 3D woven composites, containing single z-yarns and double z-yarns, were considered. The FE models were guided by experimental observations from SBS tests for the same material systems. A series of mechanisms including creation and evolution of matrix cracks and delaminations were modeled discretely. The force-displacement curves obtained from the FE simulations were compared with those from experiments. Further parametric studies were conducted to investigate the effects More >

F. Wang^1,2, D.M. Zhang^1,2,3, H.H. Zhu⁴, H.W. Huang^1,2, J.H. Yin⁵

CMC-Computers, Materials & Continua, Vol.34, No.1, pp. 63-81, 2013, DOI:10.3970/cmc.2013.034.063

Abstract This paper studies the impact of overhead excavation on an existing tunnel through both field monitoring and a full 3D numerical model. It is found that the excavation induced longitudinal heave of the tunnel is uneven with maximum heave occurring below the excavation center. Even at the same cross section, the excavation induced heave is not uniform with the most significant heave occurring at the tunnel crown. The bending moments of the tunnel lining is decreased due to the overhead excavation. The axial forces of the tunnel lining generally decrease except at the tunnel invert. More >

F. Cianetti¹

Structural Durability & Health Monitoring, Vol.8, No.1, pp. 1-30, 2012, DOI:10.3970/sdhm.2012.008.001

Abstract This research activity refers to the problem of fatigue damage evaluation of mechanical components subjected to random loads. In detail, the present paper describes a procedure, developed by the author, that, starting from component modal modelling, can very quickly gives an answer to the request not only of a qualitative evaluation of its stress state but also of a quantitative and very reliable estimation of the component damage. This estimation is available (both in time and in frequency domain), regardless of the stress state recovery, only by an appropriate elaboration of lagrangian coordinates and elements stress More >

M. Demiral^1,2, A. Roy¹, V. V. Silberschmidt¹

CMC-Computers, Materials & Continua, Vol.31, No.3, pp. 157-172, 2012, DOI:10.3970/cmc.2012.031.157

Abstract A comparison of a dynamic indentation method with a quasi-static one is used to study evolution of penetration and a generated force in the indentation process. Turning (a machining process) and dynamic indentation techniques are expected to have similar ranges of strain, strain rate and stress values in the process zone of a workpiece in a case of similar kinematics and boundary conditions. Here, we study the underlying mechanics of these two techniques. Based on advanced finite-element models, similarities and differences between the indentation and turning processes are elucidated.This study demonstrates that some critical cutting More >

A. Ramachandra Murthy¹, Nagesh R. Iyer¹, B.K. Raghu Prasad²

CMC-Computers, Materials & Continua, Vol.30, No.2, pp. 177-194, 2012, DOI:10.3970/cmc.2012.030.177

Abstract This paper presents the details of nonlinear finite element analysis (FEA) of three point bending specimens made up of high strength concrete (HSC, HSC1) and ultra high strength concrete (UHSC). Brief details about characterization and experimentation of HSC, HSC1 and UHSC have been provided. Cracking strength criterion has been used for simulation of crack propagation by conducting nonlinear FEA. The description about FEA using crack strength criterion has been outlined. Bi-linear tension softening relation has been used for modeling the cohesive stresses ahead of the crack tip. Numerical studies have been carried out on fracture More >

Zhaohui Xu¹, Deli Gao¹

CMES-Computer Modeling in Engineering & Sciences, Vol.89, No.1, pp. 17-24, 2012, DOI:10.3970/cmes.2012.089.017

Abstract Little is explained about the process of casing window milling for sidetracking due to lack of analytical method for its mechanical characteristic. In this paper, 3D FE models are established using the commercial finite-element software ABAQUS/Explicit to make simulation analysis for two key stages of the process including the initial stage of casing milling and the stage of full-gauge casing window milling. The models involve the effects of main drilling parameters such as reaction force, torque, speed, feed rate per revolution, and milling angle. The calculation results verify the capability and advantages of 3D FE More >

A. Ramachandra Murthy¹ , G.S. Palani¹ , Nagesh R. Iyer¹ , Smitha Gopinath¹ and V. Ramesh Kumar¹

CMES-Computer Modeling in Engineering & Sciences, Vol.86, No.5, pp. 409-434, 2012, DOI:10.3970/cmes.2012.086.409

Abstract This paper presents the details of projectile impact on reinforced concrete structural components. Nonlinear explicit transient dynamic analysis has been carried out by using finite element method. Concrete damage model has been employed to represent the nonlinear behaviour of target under impact load. Various methods of modeling of reinforcement have been explained. A brief note on equation of state for concrete, contact algorithms and nonlinear explicit transient dynamic analysis has been given. Numerical studies have been carried out to compute the response of concrete target due to impact of projectile. The computed penetration depth have More >

A.P.S. Selvadurai^1,2, H. Nikopour²

CMES-Computer Modeling in Engineering & Sciences, Vol.85, No.3, pp. 279-298, 2012, DOI:10.3970/cmes.2012.085.279

Abstract This paper examines the influence of a through crack on the overall flexural behaviour of a layered composite Carbon Fibre Reinforced Polymer (CFRP) plate that is fixed boundary along a circular boundary. Plates with different through crack configurations and subjected to uniform air pressure loading are examined both experimentally and computationally. In particular, the effect of crack length and its orientation on the overall pressure-deflection behaviour of the composite plate is investigated. The layered composite CFRP plate used in the experimental investigation consisted of 11 layers of a polyester matrix unidirectionally reinforced with carbon fibres. More >