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Self compacting concrete is also referred as super workable concrete as well as highly flowable concrete which are widely used as innovative material in the fast growing construction industry because of its hardened and fresh state properties. In recent days availability of river sand is less and also focus is more on sustainability development and hence there arose a situation for developing an alternative material by using the industrial waste. In this research work, complete replacement of natural sand by processed slag sand and the properties of SCC determined by using Nan-su method of mix design with incorporating EFNARC guidelines. At present days, the favorite material for the column strengthening is fiber reinforced polymer (FRP). The construction industry requires the sustainable development along with increase in strength. Therefore, column is wrapped by using natural jute fiber by varying number of wrapping layers and the structural behaviour of columns are assessed. A three-dimensional finite element (FE) model has been developed to simulate the behaviour of rectangular SCC columns wrapped with jute fiber. The developed FE model is validated by comparing the loaddisplacement responses which verifies the model to use in future. The FEA results are obtained in terms of axial load vs. axial displacement, axial load-axial strain. The numerical analysis developed by ANSYS displayed a very close simulation and deflection is compared with test results at the same load. [ABSTRACT FROM AUTHOR]

Abstract: Steel pipelines used for oil and gas transportation are joined by girth welding and welds may contain weld imperfections/defects such as lack of fusion, under-cuts, porosity, slag inclusion etc. of certain height and length at certain location along the longitudinal direction of the weld. During the installation and operation, these pipelines are exposed to large plastic deformation. Fracture assessment procedures: BS7910:2005 [1] or R6 [2], are not suitable for such plastic strains (3%). The evolution of crack tip opening displacement (CTOD) of the pipeline with elliptical embedded crack in a girth weld is investigated under biaxial loading conditions using a three dimensional elastic–plastic finite element method. Based on the results, empirical formulas depicting relationship between the CTOD and the global strain are proposed. [Copyright &y& Elsevier]

Abstract: Offshore pipelines installed by reeling method are subjected to large plastic strains. When the steel pipes are joined by girth welding, both surface and embedded cracks are inevitably initiated in welding zone. The pipe lines should have adequate resistance against both crack extension by tearing and unstable fracture during installation as well as during operation. However, common flaw assessment procedures, e.g. BS 7910:2005 , are not explicitly developed for such situations with large plastic strains. The main objective of the current paper is to find a way to assess fracture capability of a practical pipeline subject to large plastic deformation. In our study, the evolution of crack tip opening displacement (CTOD) of the pipeline with semi-eliptical surface crack in weld girth is investigated under biaxial loading conditions (uniaxial tensile and internal pressure) using three dimensional elastic–plastic finite element analysis. The effects of crack depth, ratio of semi-major axis to semi-minor axis and internal pressure are examined. The results show that at moderate levels of global strain, the variation of CTOD with global strain can be well approximated by a simple linear relationship under tensile loading as well as biaxial loading conditions. Comparing the fracture assessment for the welded pipe made by BS 7910:2005 with that made by our current study, it is found that the assessment from BS7910:2005 is over conservative. A CTOD-estimation method for strain -based fracture is suggested for the pipelines when the global strain is 3%. [Copyright &y& Elsevier]