الفهرس 
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Abstract
1:-Introduction: - Ultra-high performance fiber reinforced concrete (UHPFRC) is a new class of concrete that has been developed in recent decades. UHPFRC is Advanced Cementitious Materials (ACM). It has attracted a lot of attention in recent years as a one of the most significant breakthroughs in concrete technology at the end of the 20th century when compared to NSC and HSC, UHPFRC tends to exhibit superior properties such as advanced strength, remarkable improvement in workability, high durability, long-term stability, ductility and toughness comparable to steel, improved resistance against chemical attacks, and higher penetration resistance. RPC that has been developed in 1994 by the French Company Bouygues and first application of RPC is Sherbrooke pedestrian bridge built in 1997 in Canada. 2:- Research scope: - A review is presented to illustrate the idea of UHPFRC. This includes the concepts, potential, applications and future directions of UHPC. The finite element method through the ABAQUS computer program is used. An experimental program of two groups (Ι and II) was carried out. The mechanical properties (compressive strength, split cylinder strength, and flexural strength) of UHPC were investigated and evaluated by studying the effects of using different cement, silica fume, and quartz powder contents. 3:- Research objective: - The current work includes an experimental study and finite element simulations to investigate the possibility of producing UHPC using selective locally available materials in the Egyptian market; such as ordinary Portland cement, silica fume, quartz powder, steel fibers, superplasticizer, fine quartz sand, and fine crushed dolomite (max nominal size 4.75 mm). A total of (108) mixtures were considered. To study the influence of the different dosages of cement, silica fumes and quartz on the mechanical properties of UHPFRC. 4:- Steps Study: - In this research, previous UHPC research were studied, materials used in this research were tested to determine the properties of these materials, then concrete mixes were designed using different ratios of cement, silica fume and powder quartz, hardened concrete tests were conducted, then analyze and discussed the results of these tests. A numerical investigation using nonlinear finite element (FE) analysis program (ABAQUS) was also carried out to simulate the behavior of the cube, beam, and cylinder. 5:- Summary of Study: - A compressive strength up to 172.9 MPa, a tensile strength up to 13.95 MPa and a flexural strength up to 37.5 MPa were achieved throughout this study by using local materials for samples of 900 kg/m3 cement content, 2% steel fibers by volume, 25% silica fume/cement, and 30% quartz/cement. Technology of production of this type of concrete depend on reduce the pores to the lowest possible ratio by choosing the optimum contents and optimization of the whole grain size distribution of the materials in matrix, and on the positive interaction between quartz and silica fume.