Hybrid journal (It can contain Open Access articles) ISSN (Print) 1758-7328 - ISSN (Online) 1758-7336 Published by Inderscience Publishers[449 journals]

Authors:Abdulrahman Khaleel Midhin, Abu Bakar Nabilah, Noor Azline Mohd. Nasir, Nor Azizi Safiee Pages: 293 - 306 Abstract: Rubberised concrete filled steel tube (CFST) is a potential method to utilise the crumb rubber as partial replacement of aggregate, however previous researches show weaker interfacial bond between the rubber and concrete. The aim of this research is to investigate the bond behaviour between the steel tube and the concrete in CFST. Push-out and mechanical tests were conducted on circular specimens, and the variables were: 1) different thicknesses of steel tube; 2) concrete types (normal, rubberised concrete and presence of metakaolin as pozzolan). The results indicated that the use of rubber gives adverse effect on the compressive and splitting tensile strengths, and the modulus of elasticity. However, the use of metakaolin as cement replacement improves its mechanical properties. Based on push-out test, the rubberised concrete shows lower bond strength, and the bond strength increases with increasing section thickness. The presence of metakaolin yielded higher bond strength compared with other mixes. Keywords: rubberised concrete; concrete filled steel tube; bond-slip relation Citation: International Journal of Structural Engineering, Vol. 10, No. 4 (2020) pp. 293 - 306 PubDate: 2020-09-28T23:20:50-05:00 DOI: 10.1504/IJSTRUCTE.2020.109850 Issue No:Vol. 10, No. 4 (2020)

Authors:Roghayeh Abbasiverki, Anders Ansell Pages: 307 - 329 Abstract: Buried pipelines are tubular structures that cross large areas with different geological conditions. During an earthquake, imposed loads from soil deformations on pipelines may cause drastic damages. In this study two dimensional finite element models of pipelines and surrounding soils are used for simulation of seismic waves that propagate from the bedrock through the soil. The models describe both longitudinal and transverse cross-sections of pipelines and the soil-pipe interaction is described as a nonlinear behaviour. The effects of uniform ground with different burial depth and soil layer thickness, soil stiffness and non-uniform ground on the seismic response of reinforced concrete pipelines is studied. Two earthquakes, with high and low frequency contents, are employed for the dynamic analysis. The results show a significant effect on the response due to non-uniform ground caused by inclined bedrock, especially for high frequency earthquake excitations. Keywords: buried pipelines; high frequency; finite element; seismic analysis; non-uniform ground; soil stiffness Citation: International Journal of Structural Engineering, Vol. 10, No. 4 (2020) pp. 307 - 329 PubDate: 2020-09-28T23:20:50-05:00 DOI: 10.1504/IJSTRUCTE.2020.109854 Issue No:Vol. 10, No. 4 (2020)

Authors:S.P. Challagulla, C. Parimi, Jagadeesh Anmala Pages: 353 - 379 Abstract: The effect of a flexible secondary system (FSS) on the design spectra is studied in this paper. An FSS affects the primary structure (PS) during ground excitation differently than a secondary system that is rigidly attached to it. A modal superposition analysis is performed on a 2DOF system (PS + FSS). The influence of various parameters such as mass ratio and length of FSS on the design spectra is addressed. A methodology to estimate the spectral acceleration of the PS with FSS is developed. A design expression is proposed using statistical nonlinear regression and artificial neural network (ANN) to estimate the spectral acceleration of PS with FSS as a function of the structural period, length of FSS, and mass ratio. ANN modelling is proved to be more efficient than nonlinear regression model. An example calculation is shown for the estimation of spectral acceleration of the PS using ANN and nonlinear regression models. Keywords: primary structure; flexible secondary system; FSS; design spectra; seismic zones; artificial neural network; ANN; nonlinear regression; NLR Citation: International Journal of Structural Engineering, Vol. 10, No. 4 (2020) pp. 353 - 379 PubDate: 2020-09-28T23:20:50-05:00 DOI: 10.1504/IJSTRUCTE.2020.109857 Issue No:Vol. 10, No. 4 (2020)

Authors:Mustafa Batikha, Yara Mouna Pages: 380 - 404 Abstract: In this research, the effects of imperfections in a steel plate shear wall (SPSW) used to strengthen a reinforced concrete (RC) frame were numerically examined using nonlinear finite element analysis. Three types of structures were analysed in this study: SPSW only, a one-story RC frame with an SPSW infill, and a multi-story RC frame with an SPSW. It was determined that the initial imperfections of a thin SPSW cause a dramatic reduction in the yield and ultimate capacity of the SPSW when analysed individually; however, the presence of RC boundary frame members addresses an important role in eliminating this reduction. In contrast, it was found that the SPSW prevents the shear cracking in the RC frame joints. Based on this point, a higher RC frame capacity together with high initial stiffness and ductility are registered when an SPSW is applied, and equations for estimating the system capacity were derived through this study. Keywords: concrete frame; steel plate shear wall; SPSW; strengthening; finite element analysis; FEA; pushover lateral loading Citation: International Journal of Structural Engineering, Vol. 10, No. 4 (2020) pp. 380 - 404 PubDate: 2020-09-28T23:20:50-05:00 DOI: 10.1504/IJSTRUCTE.2020.109859 Issue No:Vol. 10, No. 4 (2020)