Low-viscosity high-early-strength polyurethane repair material for high speed railway slab ballastless track filling layer open joint repair

Abstract

The invention discloses a low-viscosity high-early-strength polyurethane repair material for high speed railway slab ballastless track filling layer open joint repair. The repair material consists of two parts, namely a part A and a part B, wherein the part A consists of the following raw materials in parts by mass: 100 parts of isocyanate and prepolymers thereof; the part B consists of the following raw materials in parts by mass: 60-80 parts of reactive hydrogen oligomer, 40-70 parts of a plasticizer, 0.5-2 parts of a defoaming agent and 0.1-1 part of an anti-aging agent; and the volume ratio of the part A to the part B is 1:1. The polyurethane open joint repair material has the advantages of low viscosity, high curing speed, high mechanical strength, high adhesive strength, high toughness and excellent durability, can meet the requirements on rapid construction in skylight time and instant traffic service after repair and can be used for rapid maintenance of the operating high speed railway slab ballastless track structure.

Description

technical field [0001] The invention belongs to the field of high-speed railway maintenance and maintenance, and in particular relates to a low-viscosity, high-early-strength polyurethane repair material for repairing gaps in filling layers of high-speed railway slab-type ballastless tracks. Background technique [0002] The slab ballastless track has become the main track structure type adopted by the 300 km / h high-speed railway in my country because of its high track smoothness, good stiffness uniformity, and strong stability. my country's Beijing-Shanghai, Beijing-Shiwu, Beijing-Tianjin, Jinqin, Harbin-Dalian, Shanghai-Nanjing, Shanghai-Hangzhou, Ninghang, Hangzhou-Ningbo, Hebeng and other high-speed railways all adopt slab ballastless track structure. The slab ballastless track structure is mainly composed of prefabricated track slabs, filling layers, concrete bases or hydraulic support layers, etc. The track slabs in the CRTS I slab ballastless track structure adopt a u...

AI Technical Summary

Problems solved by technology

[0005] 1. Low early strength: Although the existing polyurethane repair materials can accelerate the reaction speed by adjusting the catalyst, the degree of early curing is limited, and the early mechanical strength is low, which cannot meet the needs of immediate traffic after repair

[0006] 2. High viscosity: The viscosity of existing polyurethane repair materials is relatively high, generally above 500mPa·s, and the gap cannot be fully filled in a short period of time (≤20min). At the same time, the viscosity of the material increases with time, and the flow The resistance is greatly reduced, and there will be more hollow areas inside the seam, which seriously affects the repair quality

[0007] 3. Poor flexibility: The existing polyurethane repair materials mainly reflect the mechanical strength, and the flexibility is low. When subjected to the dynamic load and lateral force of the train for a long time, it is prone to brittle fracture

[0008] 4. Poor environmental adaptability: at lower temperatures (5-15°C), the reaction speed of polyurethane repair materials decreases, which cannot meet the needs of rapid repair; Wet bonding strength is low, and the repair effect drops significantly

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