Low shrinken, fireproof, high leakage resisted material of duct piece for shield tunnel, and preparation method

Abstract

This invention relates to a method for preparing ireproof shield tunnel segment material with low shrinkage and high impermeability. The material is prepared from: cement 360-400kg / m3, fly ashes 80-120 kg / m3, fine aggregate 690-720kg / m3, coarse aggregate 1100-1180 kg / m3, humidity supplementary medium 50-150 kg / m3, fibers 0.8-2 kg / m3, expanding agent 20-30 kg / m3, water (the water / colloid is 0.29-0.32), and high-performance naphthalene-based water reducer (the amount is 1.3-1.6 wt.%). The material has such advantages as good durability, high size stability, and good fireproof performance.

Description

technical field [0001] The invention relates to a high-performance shield tunnel lining segment material and a preparation method thereof. Background technique [0002] With the continuous development of China's urbanization process, the urban population will inevitably increase, but the urban land will be used less and less. In order to alleviate the urgent need of urban development, the large-scale development of urban underground space has become an inevitable trend. In the next few decades, my country's infrastructure construction will pay more attention to the construction of underground facilities. Cross-river and sea-crossing tunnels and urban rail transit will become the focus of construction. The most common method for tunnel construction is shield tunneling. construction method. In the shield method, the tunnel lining structure is assembled from several prefabricated segments or blocks. The segments must meet the strength and stiffness requirements of the engineer...

AI Technical Summary

Problems solved by technology

Impermeability is reflected in the performance of concrete’s resistance to water penetration and chloride ion penetration. At present, the impermeability index of domestic and foreign segments is around P12, and the anti-chloride ion diffusion coefficient is 2-4×10 -12 m 2 / s, by estimating that the service life of this segment is about 50 years, the service life of the segment concrete is short, which affects the service life of the tunnel as a whole, and it is necessary to improve the chloride ion penetration resistance of the segment concrete

The fire resistance performance of the tunnel segment material also has a great influence on the operating life of the entire tunnel. Although the shield lining segment as the main building in the shield tunnel is a non-combustible material, within a short period of time when the fire occurs, the tunnel will catch fire. The local temperature on site will rise rapidly to 1000°C. As the temperature rises, the mechanical properties of reinforced concrete components will drop sharply, which will directly affect the bearing capacity of the components and the stability of the building. leading to the collapse of the tunnel, causing serious consequences

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