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Concrete is unique and extensively conducive construction material by virtue of its excellent compressive strength, which is one of the most important and useful properties of concrete. In most structural applications, concrete is employed primarily to resist compressive stresses, which depends on plenty of factors like properties of ingredients, design method of preparation, curing conditions etc. Generally, compressive strength of concrete is referred to either cube strength or cylinder strength. The compressive strength of concrete is determined by testing cubes or cylinders made in laboratory or field or cores drilled from hardened concrete at site or from the non-destructive testing of the specimen or actual structure. The main objective of this research was to make comparison of strength between cube and cylinder using brick aggregate concrete. For this purpose, nine sets of mix proportions were made and studied the variation of strength between cube and cylinder. Along with this, variation of strengths between standard and small cylinders was also observed. Moreover, concrete was designed for two specified compressive strengths (3000 psi and 4500 psi) by American Concrete Institute (ACI) mix design procedure. Then it was casted and tested in laboratory with proper care. From the analysis of the test results, it had been found that cylinder strength was approximately 86 to 90 percent of cube strength and small cylinder strength was approximately 91 to 94 percent of standard cylinder strength.

No abstract

This paper describes the application of the two-dimensional (2D) modelling approach implemented in the open-source code Delft3D for the simulation of morphological development of a natural meandering river. A specific reach of the Dhaleshwari River (Bangladesh) for which field data has been available served as case study. The bed morphology and meander planform adjustment in the study area were simulated over a 10-year period considering a time-varying discharge scenario. The results showed that the 2D model was able to reproduce morphological characteristics such as scour depth, bank erosion and pool-riffle morphology, even though the model showed some deficiencies to reproduce bankfull channel width and transverse bed slopes. Regarding the planimetric evolution, the planform parameters (i.e., meander belt width, meander wavelength and radius of curvature) confirmed that the model results are realistic and are in agreement with results reported in the literature.