Prefabricated superimposed recycled lump concrete slab and construction method thereof

Patent metadata

Field	Value
Publication number	US-10934710-B2
Application number	US-201716472213-A
Country	US
Kind code	B2
Filing date	Nov 30, 2017
Priority date	Oct 16, 2017
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

A prefabricated superimposed recycled lump concrete slab includes a fresh concrete, demolished concrete lumps, and a reinforcement fabric at a lower part of the slab. The demolished concrete lumps can protrude from the fresh concrete, but a protruding height is no more than 25 mm, and the protruding height is controlled by assembling molds. The assembling molds comprise casting molds and a height-controlling cover plate, reinforcement-locating slots are reserved on side molds of the casting molds, and a vertical position of the height-controlling is determined by using screws, position-controlling nuts and gaskets of different thicknesses, which are located at four corners of the casting molds. A construction method of the prefabricated superimposed recycled lump concrete slab is also provided.

First claim

What is claimed is:

1. A prefabricated concrete slab, adapted to be integrated with post-casting concrete layer at a surface of the slab, the prefabricated concrete slab comprising a fresh concrete, a plurality of demolished concrete lumps and a reinforcement fabric at a lower part of the slab, the demolished concrete lumps are mixed with the fresh concrete, gaps between the demolished concrete lumps are filled with the fresh concrete, a ratio of a horizontal projected area of the demolished concrete lumps protruding from the fresh concrete to a surface area of the fresh concrete is no less than 1:3, a protruding height is no more than 25 mm, and the protruding height is limited by assembling molds; the assembling molds comprise casting molds and a height-controlling cover plate, reinforcement-locating slots are reserved on side molds of the casting molds, and a vertical position of the height-controlling cover plate is determined by using screws, position-controlling nuts and gaskets of different thicknesses, which are located at four corners of the casting molds, wherein a post-casting concrete layer is adapted to cover the slab, and the demolished concrete lumps are not exposed from the post-casting concrete layer.

2. The prefabricated concrete slab according to claim 1 , wherein the demolished concrete lumps are lumps formed by crushing waste concrete of old buildings, roads, bridges or dams after removing protective layers and all or part of reinforcements.

3. The prefabricated concrete slab according to claim 1 , wherein the fresh concrete is a natural aggregate concrete or a recycled aggregate concrete with a compressive strength no less than 25 MPa, and a thickness of the fresh concrete after casting is no less than 60 mm.

4. The prefabricated concrete slab according to claim 1 , wherein a characteristic size of the demolished concrete lumps ranges from 60 mm to 100 mm, and a mass ratio of the demolished concrete lumps to the fresh concrete ranges from 1:3 to 1:1.

5. The prefabricated concrete slab according to claim 1 , wherein the reinforcement fabric at the lower part of the slab is formed by binding two groups of reinforcements which are perpendicular to each other, and a length of the reinforcements protruding from a side surface of the slab is required to meet lapping and anchoring requirements.

6. A construction method of the prefabricated concrete slab according to claim 1 , the construction method comprising following steps:
(1) inserting reinforcements through the reinforcement-locating slots reserved on the side molds of the casting molds, and binding the reinforcements to form the reinforcement fabric at the lower part of the slab;
(2) wetting the demolished concrete lumps in advance, putting the wetted demolished concrete lumps into an empty cavity surrounded by the side molds of the casting molds, and stirring the demolished concrete lumps to make them evenly distributed in the empty cavity;
(3) pouring sufficient fresh concrete into the empty cavity surrounded by the side molds of the casting molds, then placing the height-controlling cover plate on the gaskets by lowering the height-controlling cover plate over the screw down onto the gaskets, and tightening the position-controlling nuts to prevent the protruding height from exceeding a limit value during vibrating; and
(4) vibrating the prefabricated concrete slab by using a vibrating table, and then steam curing the slab.

Assignees

• Univ South China Tech

Inventors

• Wu Bo
• Jian Simin

Classifications

• E04B5/04 Primary

  with beams {or slabs} of concrete or other stone-like material, e.g. asbestos cement (E04B5/08, E04B5/14 take precedence) · CPC title

• E04C2/526

  with adaptations not otherwise provided for, for connecting, transport; for making impervious or hermetic, e.g. sealings · CPC title

• B28B23/02

  wherein the elements are reinforcing members {(B28B23/0006 takes precedence)} · CPC title

• E04C2/26 Primary

  composed of materials covered by two or more of groups E04C2/04, E04C2/08, E04C2/10 or of materials covered by one of these groups with a material not specified in one of the groups {(of cement and mineral fibres E04C2/04)} · CPC title

• B28B1/10

  and applying pressure otherwise than by the use of presses · CPC title