US 11,773,021 B2 · Concrete vacuum tube segment for hyper-speed transportation system using ultra-high performance concrete (UHPC), and manufacturing method thereof

Abstract

The present invention provides a concrete vacuum tube segment for a hyper-speed transportation system using ultra-high performance concrete (UHPC) and a manufacturing method thereof. A concrete vacuum tube segment for a hyper-speed transportation system can be easily manufactured using UHPC, in which shrinkage and structural cracking do not occur due to mixing a binder and a short fiber to secure airtightness on the basis of a maximum fill theory, and accordingly, shrinkage of the concrete vacuum tube segment can be reduced even in a partial-vacuum state in which the magnitude of drying shrinkage is very small and quick drying occurs; when mixing the UHPC, an antifoaming agent is mixed and a circular vacuum pump is used to remove generated entrapped air to minimize the entrapped air; and a capsule-type crack healing material, which is able to repair fine cracks, is compacted to secure airtightness of the concrete vacuum tube segment.

Claims19

Dependent claims

A concrete vacuum tube segment for a hyper-speed transportation system using ultra-high performance concrete (UHPC), wherein the UHPC comprises:

100 parts by weight of cement as a binder (B);
20 to 30 parts by weight of silica fume as the binder (B);
15 to 25 parts by weight of quartz powder as the binder (B);
100 to 120 parts by weight of fine aggregate;
20 to 28 parts by weight of mixing water (W);
4 to 7 parts by weight of a high-performance water reducing agent;
and
1.6 to 2.2 parts by weight of an antifoaming agent,
wherein the UHPC is mixed with a short fiber and a capsule-type crack healing material to form a self-healing cement composite, a volume of the mixed short fiber is 1.5 to 2% of the entire volume of the self-healing cement composite, and a volume of the mixed capsule-type crack healing material is 0.5 to 2% of the entire volume of the self-healing cement composite.

6 more elements

A method of manufacturing a concrete vacuum tube segment for a hyper-speed transportation system using ultra-high performance concrete (UHPC), the method comprising:

a) mixing a fine aggregate with cement, silica fume, and quartz powder that serve as a binder (B);
b) mixing mixing water (W) so that a ratio (W/B) of the mixing water (W) to the binder (B) is 0.2;
c) mixing a high-performance water reducing agent and an antifoaming agent and manufacturing cement-based mortar using a circular vacuum mixer;
d) additionally mixing a short fiber, which is for securing a tensile force, in the circular vacuum mixer to form the UHPC;
e) additionally mixing a capsule-type crack healing material with the UHPC to form a self-healing cement composite;
f) compacting the self-healing cement composite in a formwork;
g) curing the self-healing cement composite;
and
h) removing the self-healing cement composite from the formwork to complete the concrete vacuum tube segment for a hyper-speed transportation system.

6 more elements

Dependencies are inferred from the claim text.

Concrete vacuum tube segment for hyper-speed transportation system using ultra-high performance concrete (UHPC), and manufacturing method thereof

Life of this patent

Concrete vacuum tube segment for hyper-speed transportation system using ultra-high performance concrete (UHPC), and manufacturing method thereof

Life of this patent

Abstract

Claims19