石灰石粉对可持续UHPC胶凝材料体系强度影响  

Study on the influence of limestone powder on the strength of sustainable UHPC cementitious material system

作　　者：南雪丽[1,2] 王毅[1,2] 陈浩[1,2] 李梅 唐维斌[3] NAN Xue-li;WNAG Yi;CHEN Hao;LI Mei;TNAG Wei-bin(School of Material Science and Engineering,Lanzhou Univ.of Tech.,Lanzhou 730050,China;State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metals,Lanzhou Univ.of Tech.,Lanzhou 730050,China;Gansu Province Transportat Planning,Survey and Design Institute Co.Ltd.,Lanzhou 730050,China)

机构地区：[1]兰州理工大学材料科学与工程学院,甘肃兰州730050 [2]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,甘肃兰州730050 [3]甘肃省交通规划勘察设计院股份有限公司,甘肃兰州730050

出　　处：《兰州理工大学学报》2024年第6期113-118,共6页Journal of Lanzhou University of Technology

基　　金：甘肃省自然科学基金(20JR10RA170);甘肃省住房和城乡建设厅项目(JK2021-11);甘肃省交通厅科研项目(2017-16,2017-19)。

摘　　要：为探究石灰石粉(LP)对可持续超高性能混凝土(UHPC)胶凝材料体系强度的影响,研究了LP取代水泥4%、8%和12%后UHPC胶凝材料体系的抗压强度、孔结构、相组成及微观结构变化,并运用生命周期理论(LCA)对环境效应进行了量化评估.结果表明:随LP取代率增加,抗压强度先增加后减小,LP取代率对总孔隙率变化趋势与强度变化趋势相反,最佳取代率为4%,相对于空白组(LPC)抗压强度和总孔隙率分别提升16.7%和降低了28%;LP未参与水化,起到填充和晶核作用,细化孔结构,取代率大于4%时稀释作用占主导地位;LP取代率大于4%时,显著减小对环境的不利影响,但对试件强度和内部结构将产生负面效应,所以在保证试件强度的条件下,应尽可能增大LP取代率.In order to investigate the effect of limestone powder(LP)on the strength of sustainable ultra-high performance concrete(UHPC)cementitious material systems,the compressive strength,pore structure,phase composition,and microstructure of UHPC cementitious material systems after 4%,8%and 12%replacement of cement by LP were investigated.Additionally,the environmental effects were quantitatively assessed using life cycle theory(LCA).The results showed that as the LP substitution rate increases,the compressive strength initially increased and then decreased with an inverse trend observed for the total porosity.The optimal substitution rate was 4%,which resulted in a 16.7%increase in compressive strength and a 28%reduction in total porosity compared to the blank group(LPC).LP does not participate in hydration but contributes to pore structure refinement through filler and nucleation effects.When the substitution rate exceeds 4%,dilution effects predominate.LP substitution rate greater than 4%significantly reduces the adverse effect on the environment but will have a negative effect on the strength and internal structure of the specimen.Therefore,the LP substitution rate should be increased as much as possible under the condition of ensuring the strength of the specimen.

关 键 词：石灰石粉 超高性能混凝土 力学性能 微观结构 环境效应 

分 类 号：TU375[建筑科学—结构工程]