In high-temperature environments, early-strength water-reducing admixture products are prone to decay and deterioration due to factors such as the addition of sugar retardant materials, and a foul odor will occur, which will lead to a decline in the performance of early-strength water-reducing admixture products and affect concrete production. .
The prevention methods are as follows:
(1) Add preservatives during the compounding process
In the production process of early-strength superplasticizer, compounding a part of preservatives can Effectively improve the deterioration of early-strength water-reducing agent. At present, the mainstream preservative addition amount on the market is 0.5~1.5kg per ton of early strength water reducing agent. The cost increases by about 10 to 25 yuan.
(2) Choose high-quality sodium gluconate retarder
Currently there are many sodium gluconate manufacturers on the market, and manufacturers with strict production control systems can Effectively control the residual amounts of glucose and Aspergillus niger, and reduce the risk of spoilage of early-strength water-reducing agents.
(3) Pay attention to the storage environment of early-strength water-reducing admixture
Try to store early-strength water-reducing admixture in a cool, ventilated place without direct sunlight. The author once conducted a test and placed one part of the early-strength water-reducing agent in a cool place without direct sunlight, and one part in a storage bottle that can be exposed to direct sunlight. Early-strength water-reducing agents placed in storage bottles exposed to direct sunlight will quickly become moldy and black.
(4) Reasonably estimate the amount of early-strength water-reducing agent used in the project
In some engineering projects, due to the impact of project progress, weather environment and other factors, early-strength water-reducing admixture The speed of agent use is often difficult to control. In some projects, the early-strength superplasticizer has been left on the construction site for more than 3 months or even longer, and deterioration often occurs. Therefore, the author recommends that manufacturers communicate with the engineering project office about the product usage progress and cycle before delivery.
(5) Reduce the use of formaldehyde, nitrite and other preservatives
Currently, some admixture manufacturers use formaldehyde, sodium benzoate and strongly oxidizing nitrite for preservatives. The cost is relatively low, but the effect is not good. At the same time, formaldehyde will escape with changes in time, temperature, PH and other factors, and deterioration will still occur. Try to use high-quality fungicides for compound use. For admixture storage tanks that have become corrupted, clean them and replenish them with new early-strength water-reducing agents. </p