摘要
目前我国许多水泥混凝土建筑物破损严重,对这些建筑物重建不仅耗资巨大,而且还将因建筑物的停用造成生产和生活方面的巨大经济损失。因此,对现有水泥混凝土建筑物的维修非常迫切,水泥基修补砂浆常常被应用在维修之中。本文通过对不同复合胶凝体系性能的试验研究,确定了胶凝材料的基准配比,选择合适的干粉砂浆外加剂,配制聚合物改性水泥基修补砂浆。
首先确定了修补砂浆中胶凝材料的配合比。硅酸盐一铝酸盐一无水石膏复合体系试验表明:在富铝酸盐水泥体系中,硅酸盐水泥掺量所占比例10%时,综合性能最好;在富硅酸盐水泥体系中,铝酸盐水泥所占比例10%时,综合性能最好。硅酸盐一硫铝酸盐一无水石膏复合体系试验表明:在富硫铝酸盐水泥体系中,普通硅酸盐水泥掺量所占比例10%时,综合性能最好;在富硅酸盐水泥体系中,硫铝酸盐水泥熟料掺量所占比例9%时,综合性能最好。
然后添加不同的矿物掺合料、不同共聚单体的可再分散乳胶粉对修补砂浆进行改性。结果表明:掺加磨细矿粉的修补砂浆基本性能要优于粉煤灰和基准砂浆;可再分散乳胶粉的加入使得修补砂浆的粘结强度随着胶粉掺量的增加而逐渐升高。在同一水平进行比较发现:不同可再分散乳胶粉对修补砂浆粘结强度影响规律为b>a>c>d。
最后在修补砂浆中掺入高效减水剂和消泡剂,改变修补砂浆的灰砂比,测试修补砂浆的基本性能。结果表明:高效减水剂和消泡剂的掺入可以显著提高修补砂浆的抗压强度和抗折强度;随着灰砂比的提高,修补砂浆的抗压强度、抗折强度和粘结强度逐渐升高。
利用扫描电镜对可再分散乳胶粉在修补砂浆中微观结构进行了分析,可再分散乳胶粉的加入,使修补砂浆的结构致密、并以聚合物膜及化学键的形式存在于修补砂浆中,提高了修补砂浆的粘结强度。
关键词修补砂浆;可再分散乳胶粉;机理
AB STRACT
At present,many concrete buildings were damaged seriously in china.The repair of these buildings was not only costly but also resulted in the great economic losses by reason of the buildings were out of production and life.Therefore,the repair of concrete buildings Was urgent.Repair mortar was often used in the repair.
Based on the study to the performance of different systems of cementitious materials,the paper determined the ratio of cementitious materials,then chose suitable additives ofdrymixed mortar,confected the repair mortar in the end.
First of aU,the paper determined the ratio of cementitious materials in the repair mortar.The test of Portland·Aluminate—Anhydrous gypsum composite system showed that:In the rich aluminate cement system,when the proportion of Portland
cement was 10%,properties of the system were the best.In the rich Portland cement system,when the proportion of aluminate cement was 1 0%,properties ofthe system were the best.The test of Portland·Sulphoaluminate·Anhydrous gypsum composite system showed that:In the rich sulphoaluminate cement system,when the proportion of Portland cement was 10% properties of the system were the best.In the rich Portland cement system,when the proportion of sulphoaluminate cement
clinker Was 9%,properties of the system were the best.
Then we added mineral admixture and redispersible powder of different comonomer to repair mortar.The results showed that:The basic properties of repair mortar which mixed witll slag were superior to repair mortar which mixed with fly ash.With the increase of the amount of redispersible powder,the bond strength of repair mortar was increased.Compared the redispersible powder at the same level,
we found that:The effects of different redispersible powder on bond strength of repair mortar were b>a>c>d.
目前我国许多水泥混凝土建筑物破损严重,对这些建筑物重建不仅耗资巨大,而且还将因建筑物的停用造成生产和生活方面的巨大经济损失。因此,对现有水泥混凝土建筑物的维修非常迫切,水泥基修补砂浆常常被应用在维修之中。本文通过对不同复合胶凝体系性能的试验研究,确定了胶凝材料的基准配比,选择合适的干粉砂浆外加剂,配制聚合物改性水泥基修补砂浆。
首先确定了修补砂浆中胶凝材料的配合比。硅酸盐一铝酸盐一无水石膏复合体系试验表明:在富铝酸盐水泥体系中,硅酸盐水泥掺量所占比例10%时,综合性能最好;在富硅酸盐水泥体系中,铝酸盐水泥所占比例10%时,综合性能最好。硅酸盐一硫铝酸盐一无水石膏复合体系试验表明:在富硫铝酸盐水泥体系中,普通硅酸盐水泥掺量所占比例10%时,综合性能最好;在富硅酸盐水泥体系中,硫铝酸盐水泥熟料掺量所占比例9%时,综合性能最好。
然后添加不同的矿物掺合料、不同共聚单体的可再分散乳胶粉对修补砂浆进行改性。结果表明:掺加磨细矿粉的修补砂浆基本性能要优于粉煤灰和基准砂浆;可再分散乳胶粉的加入使得修补砂浆的粘结强度随着胶粉掺量的增加而逐渐升高。在同一水平进行比较发现:不同可再分散乳胶粉对修补砂浆粘结强度影响规律为b>a>c>d。
最后在修补砂浆中掺入高效减水剂和消泡剂,改变修补砂浆的灰砂比,测试修补砂浆的基本性能。结果表明:高效减水剂和消泡剂的掺入可以显著提高修补砂浆的抗压强度和抗折强度;随着灰砂比的提高,修补砂浆的抗压强度、抗折强度和粘结强度逐渐升高。
利用扫描电镜对可再分散乳胶粉在修补砂浆中微观结构进行了分析,可再分散乳胶粉的加入,使修补砂浆的结构致密、并以聚合物膜及化学键的形式存在于修补砂浆中,提高了修补砂浆的粘结强度。
关键词修补砂浆;可再分散乳胶粉;机理
AB STRACT
At present,many concrete buildings were damaged seriously in china.The repair of these buildings was not only costly but also resulted in the great economic losses by reason of the buildings were out of production and life.Therefore,the repair of concrete buildings Was urgent.Repair mortar was often used in the repair.
Based on the study to the performance of different systems of cementitious materials,the paper determined the ratio of cementitious materials,then chose suitable additives ofdrymixed mortar,confected the repair mortar in the end.
First of aU,the paper determined the ratio of cementitious materials in the repair mortar.The test of Portland·Aluminate—Anhydrous gypsum composite system showed that:In the rich aluminate cement system,when the proportion of Portland
cement was 10%,properties of the system were the best.In the rich Portland cement system,when the proportion of aluminate cement was 1 0%,properties ofthe system were the best.The test of Portland·Sulphoaluminate·Anhydrous gypsum composite system showed that:In the rich sulphoaluminate cement system,when the proportion of Portland cement was 10% properties of the system were the best.In the rich Portland cement system,when the proportion of sulphoaluminate cement
clinker Was 9%,properties of the system were the best.
Then we added mineral admixture and redispersible powder of different comonomer to repair mortar.The results showed that:The basic properties of repair mortar which mixed witll slag were superior to repair mortar which mixed with fly ash.With the increase of the amount of redispersible powder,the bond strength of repair mortar was increased.Compared the redispersible powder at the same level,
we found that:The effects of different redispersible powder on bond strength of repair mortar were b>a>c>d.