The adding of silica fume to mix is becoming a huge benefit due to an improvement of mechanical properties. The percent of adding is very important to get targeted mechanical properties. This study investigates the behaviour of polymer modified concrete (PMC) modified with different percentages of silica fume as a percentage of cement weight. Using silica fume powder leads to improve the behaviour of the stress-strain diagram until 10% from the weight of cement, and to increase the values of modulus of elasticity. More dosages of silica fume decrease the modulus of elasticity. The modulus of elasticity increased from 27932 MPa for reference mixes to 43029 MPa for mixes having 10% silica fume powder. Also the of flexural strength increases by increasing silica fume to 12.5%, then after this value is dropped. All of the tensile strength, flexural strength, and modulus of elasticity have been studied in this investigation.

The aim of this article is to investigate the effect of using reactive powder concrete (RPC) for reinforcement concrete deep beams (CDBs) to study the shear effect by the numerical analysis. The method of finite element analysis model simulations using a program was used. The characteristics of RPC and the deep beam of reinforced concrete were obtained from previous scientific research. Non-linear analysis for two models of deep beams, one with RPC and the other without using it, was conducted to compare with experimental results from recent tests of deep concrete beams with RPC and loaded until failure. The data obtained from the specimens have many factors related to the effect of the strength and action of reinforcement CDBs such as shear load deflection, crack pattern, mode failure, and concrete strength. On the other hand, the mesh changing was investigated in terms of the maximum concrete strength and the running time by changing the mesh size to 50, 25, and 15. Models were simulated with a two-point load using a shear span-to-depth with an av/d ratio of 0.77. The difference in percentage deflection between the numerical and experimental models’ data was observed at 2.60 and 5.9% for concrete deep beam and RPC deep beam, respectively, and the maximum shear load was 2.27 and 5.40%. The importance of the outputs of this article lies in bridging the research gap of this new topic and identifying the shear behavior of deep beams reinforced with RPC due to the lack of research related to this topic. It was noted that the obtained data for finite element analysis are very consistent with the previous laboratory scientific research, while the error rate did not exceed 10%.

Portland cement-based grouting compound is called GP-Grout employed to produce a sort concrete as a replacement from the weight of cement in mixes and strengthened with steel nails to enhance the mechanical properties. GP-Grout replaced cement by 25%, 50% and 75% while the steel nails as locally steel fibres were used with 0.25%, 0.5%, 1%, 2 % and 3% by volume of concrete. GP-Grout powder enhanced mechanical properties of ordinary concrete especially; the compressive strength by increasing from 34 to 70 MPa as well as other properties including tensile and flexural strength with clear improvement by adding the steel nails at a ratio of 3% by volume and the results were 5.67, 9.81 MPa respectively.

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