干湿循环对矿产废渣混合砂浆的力学性能影响研究  

Study on the Effect of Dry-wet Cycle on the Mechanical Properties of Mineral Waste Slag Mixed Mortar

作　　者：张海林 ZHANG Hailin(China Railway Urban Constwction Group Nanchang ConstTuction Co.Ltd.,Nanchang Jiangxi 330002,China)

机构地区：[1]中铁城建集团南昌建设有限公司,江西南昌330002

出　　处：《铁道建筑技术》2021年第5期17-22,共6页Railway Construction Technology

基　　金：中铁城建集团科技研发计划项目(ZTCJ7-2019-04)。

摘　　要：对采用0~100%的镍铁矿渣(FNS)代替天然砂、用30%的粉煤灰及磨细高炉矿渣(GGBFS)代替水泥而配制成的水泥砂浆的强度和耐久性进行了研究。通过砂浆试件在23 ℃交替湿化和110℃烘干28次后的抗压强度和质量变化来评价耐久性,随着FNS含量的增加,其强度损失随之增加,质量损失也略有增加;当FNS的掺入量为50%时,砂浆抗压强度最高。对于粉煤灰掺量为30%的混合砂浆,当FNS含量为25%~100%时,强度损失最大可达26%,质量损失仅为3.9%~6.4%。粉煤灰的火山灰反应有助于减少干湿循环引起的强度损失。总体而言,50% FNS和30%粉煤灰的渗透孔隙体积(VPV)和干湿循环性能优于100%普通硅酸盐水泥和天然砂。This paper mainly studies the strength and durability of cement mortar prepared by using 0~100%nickeliron slag(FNS)instead of natural sand and 30%fly ash and grind blast furnace slag(GGBFS)instead of cement.The durability is evaluated by the change of compressive strength and mass of mortar specimens after alternating humidification at 23 and drying at 110℃for 28 times.With the increase of FNS content,the strength loss increases,and the mass loss increases slightly.When the amount of FNS is 50%,the compressive strength of mortar is the highest.For the mixed mortar with fly ash content of 30%,when the FNS content is 25%~100%,the strength loss is up to 26%,and the mass loss is only 3.9%~6.4%.The XRD data show that the pozzolanic reaction of fly ash helps to reduce the strength loss caused by the dry-wet cycle.In general,the permeability pore volume(VPV)and dry-wet cycle performance of 50%FNS and 30%fly ash are better than that of 100%ordinary Portland cement and natural sand.

关 键 词：抗压强度 干湿循环 矿渣 混合砂浆 孔隙率 

分 类 号：TU758.1[建筑科学—建筑技术科学]