The characteristics of rail cement products.
1. High intensity of early strength: over 20 Mpa per day.
2. The flow is also large: the flow can reach 200-300mm, which can fill all the gaps and meet the requirements of two grouting.
3. No shrinkage: ensure equipment foundation and tight integration.
4. Low temperature construction: allow building outdoor minus 10 ℃ under the temperature requirements.
5. Good insulation: high density structure hardening, good non-insulation performance.
6. Strong durability: this product belongs to inorganic cement material, and the service life is longer than the foundation of concrete. After millions of fatigue tests, there was no significant change in the strength of the 50 freeze-thaw cycle. After 30 days of immersion, the strength did not change significantly.
The reinforcement method of high strength grouting material instead of concrete.
The method is suitable for the concrete beam, column and other bearing capacity of compression zone. The replacement method is to clarify the original defect and replace it with new concrete. Its advantage is that the appearance of the component can restore the original after reinforcement, do not tamper with the existing space and building space (construction clearance are not affected), but the method also does not mainly practical and long-term construction defects, eliminate the old concrete is great, need to influence the surrounding area, the structure of the original need drugs do support and temporary reinforcement.
When packing cooling by heating and cooling contraction, coupled with the track cement itself in the process of grouting in curing shrinkage, the two are responsible for a large number of contraction stress by the constraints of matrix, and when the shrinkage stress exceeds the ultimate tensile strength of grouting materials, became a filling structural cracks, the cracks tend to occur within the orbital cement material, but the whole section serious breakdown. This layer is a long-term water pressure (especially in the high water area) is formed, by injection and material of surface and internal micro cracks, the crack not only visible to the naked eye, but also accompanied by penetrating phenomenon.Shrinkage cracks caused by shrinkage and external environmental changes (temperature, humidity, etc.) during hardening of floor packing.