The Static Mechanical Properties And Anti-penetration Characteristics Of Ultra-high Performance Cementitious Composites

With the development of new earth-penetrating weapons, the more strong military fortification is needed. How to improve the survival rate of future military command center becomes an urgent problem. This paper is based on the preparation principle of ultra high performance cementitious composites (UHPCC). The active mineral materials were used to ensure UHPCC have physical and chemical properties. The UHPCC have better static mechanical properties by superplasticize,multi-scale fibers and high-strength aggregate.Using ordinary molding process and several curing system, the ultra high performance cementitious composites were prepared which have 150MPa-270MPa compressive strength and 30MPa-55MPa flexural strength. The UHPCC have better static mechanical properties by adding steel fibers,organic fibers and inorganic nonmetallic fibers with different length and volume fraction. The hydration process of the UHPCC was analysed under different curing conditions using XRD and SEM. The microstructure of C-S-H gel was elaborated. The interface bonding between the steel fibers and the matrix was researched in the microscopic view. The mechanism of macroscopic mechanical properties was discovered.Based on static mechanical properties, the performance of UHPCC was researched in different curing system using the 79-style sniper rifle. From different scales and in different volume fractions of fiber, high-strength aggregate and different curing system to study the anti-penetration performance of UHPCC and damage shape and penetration depth.A penetration depth equation Zm was proposed associating with the compressive strength of UHPCC based on the existing empirical formula and the first penetration depth of UHPCC.Obtained the mixture ratio of UHPC with the optimal static mechanical properties:(1) cement:silica fume:ultra fine slag:water-reducing agent:steel fiber(13mm):water: sand=1:0.4:0.6:0.04:0.45:0.38:2.4According to the depth of actual penetration, Proposed the optimal mixture ratio under anti-penetration performance of UHPC:(2)cement:silica fume:ultra fine slag:water-reducing agent:steel fiber(13mm):basalt fiber:water:sand=1:0.4:0.6:0.04:0.45:0.05:0.38:2.4。(3) cement:silica fume:ultra fine slag:water-reducing agent:steel fiber(13mm):basalt aggregate:water:sand=1:0.4:0.6:0.04:0.45:1.2:0.38:2.4。...