Research On The Performance Of Dry-mixed Mortar Mixed With Mineral Thickening Admixture

Dry-mixed mortar is widely used for its properties of excellent quality, convenient construction, multifunction effect in Europe, Japan, USA and other counties. Its technology is just at the beginning in China. In this research, we studied steel slag powder (G powder), along with other admixtures such as water-retentive addition, thickening addition, set accelerating addition and others. Each constituent optimization percentage in the Dry-mixed mortar was explored by an orthogonal design test. The effects of these mineral admixtures on flow ability of DM7.5 were analyzed. A new type of mineral thickening admixture for mortar, which can not only save cement, but also improve the performance, is found. The experimental results show that the separation of the fresh mortar is lower than 25mm at the consistency of 100mm.The main performance of Dry-mixed mortar is also studied in the test. Compared with the traditional mortar, it has better performance, the experimental results show that it has preferable dry shrinkage and long-time strength and durability. The proportion of slag admixture in the mortar ranges from 30 to 45 percent of the total cementitions materials. SEM study results showed lower porosity with better poresize distribution, it was this kind of wonderful micro-pore system that supported the good performance of Dry - mixed mortar's long-time strength and durability. The engineering application of the Dry-mixed mortar has also been discussed . The great social and economic benefit will be brought forth by using this product widely in the construction.