High-performance initial-stage sprayed concrete for high-earth temperature tunnel and preparation method thereof

Abstract

The invention discloses a high-performance initial-stage sprayed concrete for high-earth temperature tunnel. The sprayed concrete is characterized in that: raw materials and amounts of per cubic meter of concrete are as follows: cement 300-400kg, fine sand 400-500kg, a blast furnace heavy slag 700-800kg, coal ash 60-100kg, an alumina clinker 40-80kg, a basalt fiber 20-40kg, a polycarboxylic acid high performance water reducer 3-5kg, an aluminate accelerator 10-15kg, and water 180-250kg. A preparation method comprises the following steps: preparing materials; carrying out mixing and stirring; adding a coarse aggregate; adding an aluminate accelerator, and spraying and pouring the concrete. Compared with the prior art, the invention has the advantages that: the sprayed concrete for supporting the high-earth temperature tunnel can be tightly combined with surrounding rocks, so that the surrounding rocks are integrally stable, and a concrete layer can be continuously sprayed for a next step of construction. In the high-earth temperature tunnel environment, the concrete has the advantages of fast solidification speed, good heat resistance, good anti-permeability and anti-cracking performance, the intensity is not reduced, so the construction requirement is met.

Description

technical field [0001] The invention relates to the field of building materials, in particular to a high-temperature tunnel high-performance primary shotcrete and a preparation method thereof. Background technique [0002] At this stage, with the rapid development of civil engineering in our country, especially the continuous development of large-scale projects such as roads and railways, many large-scale projects have to pass through mountainous areas to build deep-buried long tunnel projects, and the high-temperature and high-heat tunnel environment is the worst in the construction process. The common construction conditions also brought certain difficulties to the construction. [0003] In high-temperature and high-heat areas, the initial temperature of the surrounding rock is very high, which also makes the sprayed concrete in a high-temperature and high-heat environment. In a high temperature environment, the thermal conductivity of ordinary shotcrete is too large, whi...

AI Technical Summary

Problems solved by technology

In a high temperature environment, the thermal conductivity of ordinary shotcrete is too large, which is prone to accelerated dehydration, and insufficient cement hydration leads to a decrease in concrete strength and viscosity

[0004] An important requirement for the construction of high ground temperature tunnels is rapid construction, so it is difficult for ordinary concrete to achieve the effect of quick-setting. Even if ordinary quick-setting agents are added, it is difficult to meet the requirements, and there may be adverse effects of corrosion and strength reduction