Unlock instant, AI-driven research and patent intelligence for your innovation.

Unreinforced prestressed concrete and forming method thereof

A molding method and concrete technology, which is applied in the fields of civil engineering and transportation, to achieve the effects of saving construction costs and labor costs, good overall effects, and avoiding potential safety hazards

Active Publication Date: 2022-07-29
CHINA BUILDING MATERIALS ACAD
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The main purpose of the present invention is to provide a kind of unreinforced prestressed concrete and its forming method. The technical problem to be solved is how to obtain the unreinforced prestressed concrete with prestressed surface layer under the condition of not using reinforcement tensioning. It can not only improve the crack resistance and durability of the building, but also does not increase new investment, reduces the construction cost, and does not bring fire hazards at the same time, so it is more suitable for practical use.

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

[0062] The concrete mix ratio of the base layer: general Portland cement: 400kg, water: 150kg, stone: 980kg, sand: 680kg, polycarboxylate superplasticizer: 4kg, ultra-fine fly ash: 100kg, sodium chloride 0.4kg.

[0063] Concrete mix ratio of prestressed layer: general Portland cement: 300kg, water: 198kg, stone: 1080kg, sand: 680kg, polycarboxylate water reducer: 3kg, fly ash: 100kg, polyether shrinkage reducer 0.4kg, Calcium sulfoaluminate expansion agent 3kg.

[0064] Forming method: first pour the base concrete, then spray the styrene-butadiene emulsion interface agent on the surface of the base concrete, and then pour the prestressed layer concrete;

[0065] After testing, the shrinkage value of the base concrete in this example is 450×10 -6 , the shrinkage value of the prestressed layer concrete is 100×10 -6 , the shrinkage value of the base concrete is greater than the shrinkage value of the prestressed layer concrete, and the difference between the two deformation val...

Embodiment 2

[0067] The concrete mix ratio of the base layer: general Portland cement: 400kg, water: 150kg, stone: 980kg, sand: 680kg, naphthalene water reducer: 4kg, superfine slag: 100kg, sodium sulfate 0.4kg.

[0068] Concrete mix ratio of prestressed layer: general Portland cement: 300kg, water: 198kg, stone: 1080kg, sand: 680kg, naphthalene water reducer: 3kg, slag: 100kg, polyol shrinkage reducer 1kg, magnesia-based expansion dose 10kg.

[0069] Forming method: first pour the base concrete, after the base concrete is finally set, chisel the surface of the base concrete, spray the acrylate copolymer emulsion, and then pour the prestressed layer concrete; after it is hardened and demolded, the prestressed layer concrete is formed under pressure of unreinforced prestressed concrete.

[0070] After testing, the shrinkage value of the base concrete in this example is 450×10 -6 , the expansion value of the prestressed layer concrete is 75×10 -6 ; The base concrete shrinks, while the pre...

Embodiment 3

[0072] Base concrete mix ratio: general Portland cement: 400kg, water: 150kg, stone: 980kg, sand: 680kg, anthracene water reducer: 4kg, silica fume: 100kg, sodium nitrate: 0.4kg, polyether shrinkage reducer: 0.5kg, iron powder expansion agent 3kg.

[0073] Concrete mix ratio of prestressed layer: general Portland cement: 300kg, water: 198kg, stone: 1080kg, sand: 680kg, polycarboxylate water reducer: 3kg, stone powder: 100kg, polyether shrinkage reducer: 1kg, iron powder Department of expansion agent 20kg.

[0074] Forming method: First pour the base concrete, then insert the steel fiber vertically into the base concrete and expose the stubble, and then pour the prestressed layer concrete; after it is hardened and demolded, the prestressed layer is compressed to form the unreinforced prestressed concrete.

[0075] After testing, the expansion value of the base concrete in this example is 30 × 10 -6 , the expansion value of the prestressed layer concrete is 96×10- 6 ; The bas...

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
Elastic modulusaaaaaaaaaa
Login to View More

Abstract

The invention relates to unreinforced prestressed concrete and a forming method thereof. The unreinforced prestressed concrete comprises: a base layer which is a mortar, concrete or neat paste casting; the deformation value of the base layer is S1; the prestress layer is arranged on the surface of the base layer and completely covers the base layer; the prestressed layer is a mortar, concrete or neat paste casting piece and does not comprise reinforcing steel bars; the deformation value of the prestress layer is S2; wherein S1 is less than S2. The technical problem to be solved is how to obtain the unreinforced prestressed concrete with prestress on the surface layer under the condition of not using steel bar tension, so that the unreinforced prestressed concrete not only can improve the crack resistance and durability of a building, but also does not increase new investment, reduces the construction cost, does not bring fire-fighting hidden dangers, and is more practical.

Description

technical field [0001] The invention relates to the technical fields of civil engineering and transportation, in particular to a non-reinforced prestressed concrete and a forming method thereof. Background technique [0002] Prestressed concrete is a structure that is pre-compressed before loading, and its prestress is generated by tensioning high-strength steel bars or steel wires. There are two tensioning methods: 1) Pre-tensioning method, that is, the steel bars are tensioned first, and then the concrete is poured. When the concrete reaches the specified strength, the two ends of the steel bars are loosened; 2) The post-tensioning method, that is, the concrete is poured first, and the specified strength is reached. , re-tension the steel bars in the reserved channels in the concrete, and anchor them at both ends. The prestressed state generated by the tension of the steel bar is used to reduce or offset the tensile stress caused by the external load, that is, the higher ...

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
IPC IPC(8): C04B28/04B28B1/16B28B1/50E04B1/00E04B1/92C04B111/20
CPCC04B28/04B28B1/16B28B1/50E04B1/00E04B1/92C04B2111/00612C04B2111/20C04B14/02C04B14/06C04B2103/302C04B18/08C04B22/124C04B24/32C04B22/142C04B18/141C04B22/147C04B22/066C04B18/146C04B22/085C04B22/04Y02W30/91
Inventor 王振地王玲
Owner CHINA BUILDING MATERIALS ACAD