This paper investigates the effect of the bauxite sand and coarse aggregate on the quasi-static mechanical properties and resistance against high-velocity projectile impact of cement composites with 28-day compressive strengths from 34.2 to 197.2 MPa, in comparison to that of the siliceous sand and granite coarse aggregate. Mechanical properties investigated include compressive strength, elastic modulus, compressive stress-strain behavior, splitting tensile strength, and effective hardness index. Impact resistance was evaluated using 8.0-mm-diameter, 7.8-g-mass, conical-nosed projectiles at velocities of approximately 400 m/s. The results indicate that the bauxite sand and coarse aggregate are beneficial for enhancing mechanical properties and impact resistance of cement composites compared to the siliceous sand and granite coarse aggregate. The concrete incorporating both bauxite sand and coarse aggregate exhibits compressive strength of about 200 MPa and elastic modulus of about 105 GPa at 28 days under ambient curing conditions, and better impact resistance than a granite rock specimen. This study will provide insights into the development of advanced cement composites with superior mechanical properties and impact resistance for protective structures.

本文研究了铝土矿砂和粗骨料对28天抗压强度为34.2 MPa至197.2 MPa的水泥复合材料的准静态力学性能和抗高速弹丸冲击的影响，与硅质砂相比和花岗岩粗骨料。研究的机械性能包括抗压强度，弹性模量，压缩应力-应变行为，抗拉强度和有效硬度指数。使用直径为8.0毫米，质量为7.8克，圆锥形的抛射物，以约400 m / s的速度评估抗冲击性。结果表明，与硅质砂和花岗岩粗骨料相比，铝土矿砂和粗骨料有利于增强水泥复合材料的机械性能和抗冲击性。掺铝土矿砂和粗骨料的混凝土在环境固化条件下28天时的抗压强度约为200 MPa，弹性模量约为105 GPa，并且比花岗岩岩石试样具有更好的抗冲击性。这项研究将为开发具有卓越机械性能和防护结构抗冲击性的高级水泥复合材料提供见识。