Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

C20 concrete for preliminary bracing of tunnel steel shotcrete and die-cast shotcrete technology

A technology of sprayed concrete and primary support, which is applied in tunnels, tunnel linings, earthwork drilling and mining, etc., to achieve the effects of rapid strength growth, improved physical and mechanical properties, and strong bonding force

Inactive Publication Date: 2017-05-31
GUIZHOU HIGHWAY ENG GRP
View PDF4 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the rebound rate of sprayed concrete for the initial support of conventional tunnels is as high as 25%. How to reduce the rebound rate of tunnel construction is an urgent problem that the majority of technical personnel in highway tunnel construction are constantly exploring.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Example 1: A C20 concrete for the initial support of tunnel steel support, which is composed of cement, gravel, sand, admixture and water; wherein the gravel and sand are continuously graded; the particle size of the gravel is 4.75-9.5 mm, the particle size of the sand is 0.075-4.75mm, and the measured slump is 90mm;

[0026] The above concrete is composed of 402 parts of cement, 857 parts of crushed stone, 856 parts of sand, 24.12 parts of admixture and 185 parts of water in parts by weight; the cement label is P.O42.5; the admixture is an accelerator, Accelerator The initial setting is less than 5 minutes, and the final setting is less than 10 minutes.

Embodiment 2

[0027] Example 2: A C20 concrete for the initial support of tunnel steel support, which is composed of cement, gravel, sand, admixture and water; wherein the gravel and sand are continuously graded; the particle size of the gravel is 4.75-9.5 mm, the particle size of the sand is 0.075-4.75mm, and the measured slump is 100mm;

[0028] The above concrete is composed of 378 parts by weight, 869 parts of crushed stone, 868 parts of sand, 22.6 parts of admixture and 185 parts of water; the cement label is P.O42.5; the admixture is an accelerator, accelerator The initial setting is less than 5 minutes, and the final setting is less than 10 minutes.

Embodiment 3

[0029] Example 3: A C20 concrete for the initial support of tunnel steel support, which is composed of cement, gravel, sand, admixture and water; wherein the gravel and sand are continuously graded; the particle size of the gravel is 4.75-9.5 mm, the particle size of the sand is 0.075-4.75mm, and the measured slump is 80mm;

[0030] The above concrete is composed of 430 parts of cement, 843 parts of crushed stone, 842 parts of sand, 25.8 parts of admixture and 185 parts of water in parts by weight; the cement label is P.O42.5; the admixture is an accelerator, Accelerator The initial setting is less than 5 minutes, and the final setting is less than 10 minutes.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
slumpaaaaaaaaaa
Login to View More

Abstract

The invention discloses C20 concrete for preliminary bracing of tunnel steel shotcrete and a die-cast shotcrete technology. The concrete is prepared from cement, gravel, sand, an additive and water. The technology comprises the steps of firstly performing anchor rod hole construction on a tunnel wall according to designed intervals and performing anchor rod pouring construction in holes within hole depths; then performing outer layer reinforcing mesh laying construction, wherein a reinforcing mesh is tightly attached to a rock surface and fixed to anchor rods; then installing a steel arch in a tunnel; installing an inner layer reinforcing mesh between the steel arch, wherein the two sides of the inner layer reinforcing mesh are fixed to the steel arch; finally pressing a detachable formwork on the arch from the bottoms of the two sides of the steel arch, installing and fixing, forming a concrete cabin, spraying concrete into the concrete cabin in a mode perpendicular to the rock surface, disassembling the formwork after concrete solidifies, circularly pressing, installing and fixing the formwork to parts where concrete is not sprayed of the steel arch and performing continuous spray operation. The concrete has the characteristics of low rebound rate and moderate slump degree.

Description

technical field [0001] The invention relates to a C20 concrete and press mold shotcrete technology for tunnels, in particular to a C20 concrete and press mold shotcrete technology for tunnel steel support primary support. Background technique [0002] Concrete, referred to as "concrete (tóng)": refers to the general designation of engineering composite materials in which aggregates are cemented into a whole by cementitious materials. Generally speaking, the term concrete refers to the cement concrete obtained by using cement as the cementitious material, sand and stone as the aggregate; mixed with water (may contain admixtures and admixtures) in a certain proportion, and stirred. Concrete, which is widely used in civil engineering. Since the initial support of the tunnel must be implemented in a timely manner following the excavation surface to reduce the exposure time of the surrounding rock and inhibit the deformation of the surrounding rock. In view of the high cost of p...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C04B28/04E21D11/10E21D11/15E21D11/18E21D20/02
CPCC04B28/04C04B2111/00155E21D11/105E21D11/152E21D11/18E21D20/02C04B14/02C04B14/06C04B2103/12
Inventor 陈进余祖佳罗彦彪邹国助项海燕谢兴江袁胜勇
Owner GUIZHOU HIGHWAY ENG GRP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products