Mechanical Properties and Microstructural Analysis of Ultra High Performance Composite in Safety Scopes
In this paper, by replacing Portland cement with large dosage of ultra-fine mineral admixtures (i.e. silica fume and fly ash) as well as using bauxites as fine aggregates, ultra-high performance cementitious composites (UHPCC) with compressive strengths of 240MPa were prepared. The workability of fresh UHPCC mixture and static mechanical properties of hardened UHPCC specimens cured at 200^ oven for different periods were investigated. Then the fire-impact resistances and cooling-impact behaviors of UHPCC were also investigated. Further, XRD, DTA/TGA and SEM are employed to study the microstructures of UHPCC. The results indicated that the compressive strengths and fire-impact resistances of UHPCC increased with the curing time. The UHPCC had good mechanical properties, fire-impact resistances and coolingimpact behaviors up to the standard of ATM safes. The results of phase analysis demonstrated that the bauxite particles only act as filling materials, no chemical reaction happen between bauxite and cement paste. The high curing temperature may facilitate the hydration process of cement paste and the pozzolanic reaction of ultra-fine mineral admixtures, and consequently improve the microstructure and mechanical performance of UHPCC.
ultra-high performance cementitious composites (UHPCC) xerothermic curing mechanical properties fire-impact resistance cooling-impact behavior microstructure
Z.D Rong WSun H.S Chen S.J Zhao
JiangSu Key Laboratory of Construction Materials, Nanjing, 211189,China College of Materials Science JiangSu Key Laboratory of Construction Materials, Nanjing, 211189,China College of Materials Science
国际会议
济南
英文
920-928
2010-05-09（万方平台首次上网日期，不代表论文的发表时间）