Briefly how to formulate high strength shotcrete with compensating shrinkage properties

2022-09-07
Briefly how to formulate high strength shotcrete with compensating shrinkage properties

Reprinting is strictly prohibited
acacem.com
Dated Sep. 07, 2022

Keywords
Shotcrete, amorphous calcium aluminate, high strength, compensated shrinkage, polycarboxylate superplasticizer, microsilica

The English name of compensating shrinkage concrete is Shrinkage compensating concrete.
The expansion agent relies on its own chemical reaction or reacts with other components of the cement to produce a certain limited expansion during the concrete hardening process to compensate for the shrinkage during the concrete hardening process (mainly dry shrinkage and cold shrinkage), and the concrete expansion drives the steel bars to expand together. Expansion can stretch the steel bars and generate compressive stress in the concrete. The concrete that bears the load is called prestressed concrete.

Shotcrete is a construction method of pouring fine stone concrete by spraying with a pressure spray gun. It is often used for lining tunnel linings, walls, ceilings and other thin-walled structures or linings of other structures, as well as protective layers of steel structures. Shotcrete is to put pre-prepared cement, sand, stones, water and a certain amount of admixtures into a jet machine, and then use high-pressure air to send it to the nozzle and mix with the accelerator, and then spray it to the rock at a high speed. or the surface of concrete.

Improving the strength of shotcrete can effectively ensure the safety of the structure; at present, three important technical measures for preparing high-strength shotcrete are: reducing the water-binder ratio, adding high-activity admixtures, and adopting high-compression-strength ratio rapid-setting agent.

Amorphous calcium aluminate is currently the world's leading concrete quick-setting and setting-accelerating material. It has the characteristics of ultra-quick setting, high strength, early strength, low shrinkage, anti-seepage, small loss of late strength, low alkali, wide adaptability, etc. Series advantage performance.
Amorphous calcium aluminate can be perfectly applied to high-strength shotcrete with compensating shrinkage properties.

Recommended composition of raw materials of high strength shotcrete with compensating shrinkage properties
Amorphous calcium aluminate, polycarboxylate superplasticizer, high-strength cement, fiber, micro-silica fume, fly ash, expansion agent, fine sand, crushed stone, etc.

Reprinting is strictly prohibited
acacem.com
Dated Sep. 07, 2022