C60 High Performance Concrete (HPC) was prepared by limiting cement content and adopting compositesuperplasticizer, low-alkalinity expansive agent and high-quality line mixture. The results showed that the performance...C60 High Performance Concrete (HPC) was prepared by limiting cement content and adopting compositesuperplasticizer, low-alkalinity expansive agent and high-quality line mixture. The results showed that the performance of the prepared C60 HPC was excellent. By adopting some advanced construction techniques such as usingsecondary vibration and secondary face compaction, controlling temperature difference and paying special attentionto early curing in the construction process, the prepared C60 HPC had been successfully applied in the monolithicstructure of huge building.展开更多
Dune sand is a very abundant material in south of Algeria. Its high silica content gives a partial pozzolanic reactivity due to its crystalline state. This paper investigates the evolution of cement hydration based on...Dune sand is a very abundant material in south of Algeria. Its high silica content gives a partial pozzolanic reactivity due to its crystalline state. This paper investigates the evolution of cement hydration based on a binary addition particularly the reactivity of dune sand finely ground in the presence of an amorphous addition: silica fume or blast furnace slag. Thus, four combinations of binary additions by substitution have been chosen. The X-ray diffraction analyses performed on cement pastes containing additions have shown the importance of the mineralogy and silica content of additions on their pozzolanic reactivity. Dune sand becomes reactive at long term, especially when associated up to 10% of amorphous addition (blast furnace slag or silica fume). It results an increasing in mechanical strength of Ultra High Performance Concrete (UHPC) and an improvement of the microstructure.展开更多
通过研究废弃混凝土再生粉取代水泥(0、10%、20%、30%、40%、50%取代)对超高性能混凝土(Ultra high performance concrete,UHPC)性能的影响,验证使用废弃混凝土再生粉制备UHPC的可行性。结果表明,再生粉取代水泥降低了UHPC基体的工作性...通过研究废弃混凝土再生粉取代水泥(0、10%、20%、30%、40%、50%取代)对超高性能混凝土(Ultra high performance concrete,UHPC)性能的影响,验证使用废弃混凝土再生粉制备UHPC的可行性。结果表明,再生粉取代水泥降低了UHPC基体的工作性能和抗折强度,但使用50%的再生粉取代水泥制备的UHPC基体28 d抗压强度与基准组相当;使用废弃混凝土再生粉制备UHPC基体具有较好的抗渗性能;随再生粉取代量的增加,UHPC基体的早期自收缩下降;XRD分析结果表明使用废弃混凝土再生粉取代水泥并不改变水化产物的种类;但掺加废弃混凝土再生粉能明显缩短UHPC基体的水化诱导期,降低累积释放热。除此之外,使用废弃混凝土再生粉制备的UHPC基体能耗显著降低。展开更多
文摘C60 High Performance Concrete (HPC) was prepared by limiting cement content and adopting compositesuperplasticizer, low-alkalinity expansive agent and high-quality line mixture. The results showed that the performance of the prepared C60 HPC was excellent. By adopting some advanced construction techniques such as usingsecondary vibration and secondary face compaction, controlling temperature difference and paying special attentionto early curing in the construction process, the prepared C60 HPC had been successfully applied in the monolithicstructure of huge building.
文摘Dune sand is a very abundant material in south of Algeria. Its high silica content gives a partial pozzolanic reactivity due to its crystalline state. This paper investigates the evolution of cement hydration based on a binary addition particularly the reactivity of dune sand finely ground in the presence of an amorphous addition: silica fume or blast furnace slag. Thus, four combinations of binary additions by substitution have been chosen. The X-ray diffraction analyses performed on cement pastes containing additions have shown the importance of the mineralogy and silica content of additions on their pozzolanic reactivity. Dune sand becomes reactive at long term, especially when associated up to 10% of amorphous addition (blast furnace slag or silica fume). It results an increasing in mechanical strength of Ultra High Performance Concrete (UHPC) and an improvement of the microstructure.
基金国家自然科学基金(51608409)2016年中山市新型研发机构专项(重大研发平台建设补贴2016F2FC0008)+2 种基金广东省中山市重大科技专项(2017A1021)2016年广东省省级科技计划项目(产学研合作项目2016A090924002)National Key Research and Development Program of China(2016YFC0305101)
文摘通过研究废弃混凝土再生粉取代水泥(0、10%、20%、30%、40%、50%取代)对超高性能混凝土(Ultra high performance concrete,UHPC)性能的影响,验证使用废弃混凝土再生粉制备UHPC的可行性。结果表明,再生粉取代水泥降低了UHPC基体的工作性能和抗折强度,但使用50%的再生粉取代水泥制备的UHPC基体28 d抗压强度与基准组相当;使用废弃混凝土再生粉制备UHPC基体具有较好的抗渗性能;随再生粉取代量的增加,UHPC基体的早期自收缩下降;XRD分析结果表明使用废弃混凝土再生粉取代水泥并不改变水化产物的种类;但掺加废弃混凝土再生粉能明显缩短UHPC基体的水化诱导期,降低累积释放热。除此之外,使用废弃混凝土再生粉制备的UHPC基体能耗显著降低。
