What is the applicable temperature range for high-strength non shrink grouting material?

The applicable temperature range of high-strength non shrinkage grouting material needs to be comprehensively judged based on the construction temperature and curing temperature. The core is to ensure the normal hydration and hardening of the grouting material (to avoid low-temperature freezing or rapid water loss at high temperatures). The mainstream applicable range and special circumstances are as follows:

1. Conventional applicable temperature (recommended range)

Construction temperature: 5 ℃~35 ℃ At this temperature, the grouting material has stable fluidity and moderate hydration reaction rate after being mixed with water, which can ensure self compaction during construction (no segregation or bleeding), form strength normally, and is not prone to cracking due to temperature problems.

Curing temperature: 5 ℃~35 ℃. During the curing period (usually 7-14 days), this temperature should be maintained to ensure that the cement is fully hydrated and the expansion components are effectively utilized (to counteract shrinkage), avoiding low temperature causing hydration stagnation (strength not increasing) or high temperature causing rapid evaporation of water (surface cracking, strength decrease).

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2. Treatment at special temperatures (additional measures required)

(1) Low temperature environment (<5 ℃, especially<0 ℃)

Risk: The grouting material is susceptible to freezing (water freezes and expands, damaging the internal structure), slowing down or stopping the hydration reaction, leading to insufficient strength, hollowing and cracking.

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Response measures:

Raw material preheating: Before construction, preheat the grouting material and mixing water (can be heated to 20 ℃~30 ℃, strictly prohibited from exceeding 40 ℃) to avoid direct mixing of low-temperature raw materials;

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Post construction insulation: Immediately cover with cotton quilts, electric blankets or flame-retardant insulation films after grouting is completed, and if necessary, build insulation sheds to ensure that the curing temperature is not lower than 5 ℃;

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Choose "low-temperature specialized grouting material": some products add early strength antifreeze components, which can be used for construction at -5 ℃~5 ℃ (still requiring basic insulation).

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(2) High temperature environment (>35 ℃)

Risk: Rapid evaporation of water can cause rapid crust formation on the surface of the grouting material (surface cracking before internal hardening), rapid loss of fluidity (need to be used up faster after mixing), and may lead to high internal temperature due to concentrated hydration heat (resulting in temperature stress cracks).

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Response measures:

Cooling treatment: Construction should be carried out during low temperature periods in the morning and evening. The base (such as equipment foundation, concrete surface) should be sprinkled with water to cool down, and ice water can be added to the mixing water (control water temperature ≤ 25 ℃).

; Moisturizing maintenance: Immediately cover with moisturizing film and geotextile after grouting, frequently sprinkle water (to avoid surface dryness), and if necessary, build a sunshade; Shorten construction time: Grouting must be completed within 30 minutes after mixing to avoid insufficient fluidity.

3. Taboo Temperature

Construction is strictly prohibited when the temperature is<-5 ℃ and there are no insulation measures: even for low-temperature special types, it is easy to freeze below -5 ℃, and the strength cannot be restored after subsequent thawing;

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Avoid construction at temperatures above 40 ℃ without cooling measures: It is difficult to control water loss and hydration heat at high temperatures, which can lead to irreversible defects such as surface sanding and internal looseness.

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