A shrinkage reducing agent suitable for mass concrete

Abstract

The invention discloses a shrinkage reducing agent suitable for mass concrete. It consists of component A, component B and component C; the component B is one or any mixture of triglyceride, ethylene glycol, and neopentyl glycol; the component C is tartaric acid, lemon One of the acids or any mixture; add DMAP to the carboxylic acid and diethylenetriamine, vacuumize, heat up and stir, react for 2‑4h, add isopropanol to recrystallize after cooling, and filter to obtain component A. The shrinkage reducing agent for concrete of the present invention can effectively reduce the shrinkage of concrete by more than 50%, improve the shrinkage and cracking of concrete under the condition of strong wind and high temperature, and improve the durability of concrete; it has no adverse effect on the workability of freshly mixed concrete, and does not increase the concrete content. Gas volume: simple composition, low dosage, and no adverse effect on the strength of hardened concrete.

Description

technical field [0001] The invention belongs to the technical field of materials, and in particular relates to a shrinkage reducing agent suitable for mass concrete. Background technique [0002] From pouring to hardening of concrete, due to volume changes and the characteristics of brittle materials, cracks are unavoidable, especially for some special concrete structures, such as large-volume base plates, large-volume transfer floors, super high-rise buildings, and super-long-span bridges , Concrete cracks are mainly caused by concrete shrinkage, and concrete shrinkage is mainly caused by the migration of water in concrete. Therefore, the premise of controlling or inhibiting concrete shrinkage is to control the water migration in concrete. From the design point of view, it can improve the concrete shrinkage or the crack formation caused by shrinkage. The second is to reduce the concrete shrinkage or the cracking caused by shrinkage from the curing point of view after the co...

AI Technical Summary

Problems solved by technology

However, relevant research results show that the effective expansion of concrete mixed with expansion agent can produce self-expansion phenomenon under the condition of sealing or sufficient curing, but the shrinkage drop after expansion is lower than that of concrete without expansion agent under dry environmental conditions. bigger

Although the existing research results have proved that shrinkage reducing agents can reduce shrinkage, there are problems such as poor compatibility with other chemical admixtures and significant adverse effects on strength when using shrinkage reducing agents. Generally, the strength will be reduced by more than 10%. When the compatibility between the water reducing agent and the water reducing agent is not good, the concrete strength will be reduced more obviously, and in some cases it can be reduced by more than 15%.

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