| 摘要: |
| 为了使原材料来源更好地满足实际工程需要，通过试验成功制备了不掺硅粉的新型超高性能混凝土，即超细水泥活性粉末混凝土（SC RPC），并研究了水胶比、砂胶比、外加剂掺量、骨料粒径范围、普通水泥及矿物掺和料对SC RPC砂浆体抗压强度、（含水）孔隙率、拌和物流动度的影响.试验结果表明：超细水泥可单独作为粉料制备SC RPC；混掺30%（质量分数）粒化高炉矿渣粉、10%（质量分数）粉煤灰后材料抗压强度最高，拌和物流动度最大，且经济性较好；采用普通水泥取代部分超细水泥导致材料孔隙率增大，抗压强度降低；可针对工程需要筛分出粒径范围合适的普通河砂制备SC RPC；建议使用适量消泡剂增加材料密实度.在试验基础上建立了水胶比、孔隙率双因素控制的SC RPC砂浆体抗压强度预测模型，并给出掺入钢纤维后材料抗压强度的计算方法. |
| 关键词: 超高性能混凝土 超细水泥 配合比设计 计算模型 |
| DOI：103969/j.issn1007 9629201404018 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51378032）；北京市自然科学基金资助项目（8142005）；教育部博士点基金资助项目（20131103110017） |
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| Mix Proportion Design of Reactive Powder Concrete with Superfine Cement |
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DENG Zongcai1, XIAO Rui1, SHEN Chenliang2
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1.Key Laboratory of Urban Security and Disaster Engineering, Ministry of Education, Beijing University of Technology,Beijing 100124, China;2.Beijing Zhenghua Concrete Co., Ltd., Beijing 100061, China
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| Abstract: |
| To improve the raw material resources of ultra high performance concrete （UHPC） for construction and application, a new kind of UHPC reactive powder concrete with superfine cement (SC RPC） was prepared. And the influences of water to binder ratio, sand to binder ratio, dosage of additives, size range of aggregate of sand, replacing amount of superfine cement（SC） by ordinary Portland cement（OPC）, fly ash（FA） and ground granulated blast furnace（GGBFS） on compressive strength, void ratio and fluidity of SC RPC mortar were investigated. The test results show that SC can be used as the binder solely to prepare SC RPC. By using 30% GGBFS and 10% FA to replace the amount （by mass） of SC, the compressive strength of SC RPC mortar is the highest, the fluidity is the best. Blending with OPC caused void ratio of the material increase and compressive strength decrease. To fit the requirement of construction project, ordinary river sand with suitable size range can be used as aggregate. The suitable dosage of defoaming agent was recommended to be added into the mixture to increase the density. The computation module of the compressive strength influenced by factors of water to binder ratio and void ratio was established for mix proportion design of SC RPC mortar, and the factor of steel fiber content was also considered to calculate the compressive strength of SC RPC. |
| Key words: ultra high performance concrete superfine cement mix proportion design computation module |
