CN101694127B - Formwork support system for steel frame structure cast-in-place concrete floorslabs - Google Patents

Abstract

The invention discloses a formwork support system for cast-in-place concrete floors with steel frame structures. It includes I-shaped cross-section beams, horizontal scaffold steel pipes, vertical scaffold steel pipes, steel pipe fasteners, wooden formwork, tie rod steel pipes, and corrugated wood; two horizontal scaffold steel pipes and multiple vertical scaffold steel pipes are connected by steel pipe fasteners to form a scaffold Steel pipe truss, more than 2 scaffold steel pipe trusses and more than 2 tie rod steel pipes are connected by steel pipe fasteners, the lower end of the scaffold steel pipe truss is placed on the lower flange of the I-shaped section beam, the upper end of the scaffold steel pipe truss is placed with corrugated wood, and the upper end of the scaffold steel pipe Wood formwork. Compared with the background technology, the present invention has the beneficial effects as follows: 1) the wooden formwork is used, and the assembly can be made at will; 2) the steel pipe top support is saved, and the workload on site is reduced; 3) the formwork is supported on the lower flange of the beam in the present invention, It provides a spacious working platform for various types of work, and can work in multiple layers to speed up the construction progress.

Description

Formwork support system for cast-in-place concrete slabs of steel frame structures

technical field

The invention relates to the field of construction, in particular to a formwork support system for cast-in-place concrete floors with steel frame structures.

Background technique

Multi-high-rise buildings adopt steel structures, which have the advantages of light weight, good seismic performance, fast construction speed, and low environmental pollution. The use of steel structures in multi-high-rise buildings in my country is becoming more and more common. At present, ordinary cast-in-place concrete slabs and profiled steel-cast-in-place concrete composite slabs are widely used in steel frame structures.

But it also has the following problems:

1) Ordinary cast-in-place concrete floor slabs need to install a large number of formwork supports on the floor, and the construction progress is slow.

2) The profiled steel plate needs to be equipped with end anchors, which increases the complexity of construction.

3) If it is necessary to consider the combined effect of profiled steel plate and concrete floor slab, in addition to adopting a special form or special structure, there are also requirements for the durability and fire protection of the steel plate; otherwise, the steel plate is only used as a formwork during the construction of the floor slab, and it will lose its effect after the construction is completed. , need to consume a lot of steel.

4) The profiled steel plate cannot bear the unhardened concrete load and construction load alone, and it is necessary to set up temporary vertical supports between spans, including support trusses and steel pipe top supports supported on the floor, which slows down the construction progress and increases material costs.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a formwork support system for a cast-in-place concrete floor with a steel frame structure.

The formwork support system for cast-in-place concrete floors of steel frame structures includes I-shaped section beams, horizontal scaffolding steel pipes, vertical scaffolding steel pipes, steel pipe fasteners, wooden formwork, tie rod steel pipes, corrugated wood; 2 horizontal scaffolding steel pipes and multiple Two vertical scaffold steel pipes are connected by steel pipe fasteners to form a scaffold steel pipe truss. More than 2 scaffold steel pipe trusses are connected with more than two tie rod steel pipes by steel pipe fasteners. The lower end of the scaffold steel pipe truss is placed on the lower flange of the I-shaped section beam. The upper end of the steel pipe truss of the scaffolding is placed with corrugated wood, and the wooden formwork is placed on the corrugated wood.

When the distance between two adjacent I-shaped cross-section beams is less than 3 meters, the distance between two adjacent scaffolding steel pipe trusses is not more than 2.5 meters; when the distance between two adjacent I-shaped cross-section beams is 3 meters to 4 meters, the distance between two adjacent The distance between the steel pipe trusses of the scaffolding is not more than 1.5 meters; when the distance between two adjacent I-shaped section beams is 4 meters to 5 meters, the distance between the steel pipe trusses of two adjacent scaffoldings is not more than 0.9 meters. The height of the scaffold steel pipe truss is 10 cm to 12 cm smaller than the height of the I-shaped cross-section beam. The spacing between the horizontal scaffolding steel pipes where the corrugated wood is placed is 20 centimeters to 30 centimeters. The upper surface of the wood formwork is flush with the lower surface of the upper flange of the I-shaped section beam.

The beneficial effect that the present invention has compared with background technology is:

1) Using wooden formwork, making and assembling at will.

2) Save the steel pipe top support, reduce the workload on site.

3) In the present invention, the formwork is supported on the lower flange of the beam, which provides a spacious working platform for various types of work, can work in multi-layer three-dimensional, and speeds up the construction progress.

Description of drawings

Figure 1 is a cross-sectional view of the support arrangement;

Figure 2 is a plan view of the support arrangement;

In the figure: I-shaped cross-section beam 1, horizontal scaffolding steel pipe 2, vertical scaffolding steel pipe 3, steel pipe fastener 4, wooden formwork 5, tie rod steel pipe 6, scaffolding steel pipe truss 7, and corrugated wood 8.

Detailed ways

The formwork support system for cast-in-place concrete slabs of steel frame structures includes I-shaped section beams 1, horizontal scaffolding steel pipes 2, vertical scaffolding steel pipes 3, steel pipe fasteners 4, wooden formwork 5, tie rod steel pipes 6, and corrugated wood 8; Two horizontal scaffolding steel pipes 2 and multiple vertical scaffolding steel pipes 3 are connected by steel pipe fasteners 4 to form a scaffolding steel pipe truss 7. Scaffolding steel pipe trusses 7 with more than 2 poles are connected with more than two tie rod steel pipes 6 through steel pipe fasteners 4. Scaffolding steel pipes The lower end of the truss 7 is placed on the lower flange of the I-shaped cross-section beam 1, the upper end of the steel pipe truss 7 of the scaffolding is placed with corrugated wood 8, and the wooden formwork 5 is placed on the corrugated wood 8.

When the distance between two adjacent I-shaped cross-section beams 1 is less than 3 meters, the distance between two adjacent scaffolding steel pipe trusses 7 is not more than 2.5 meters; when the distance between two adjacent I-shaped cross-section beams is 3 meters to 4 meters, The distance between two adjacent scaffolding steel pipe trusses 7 is not greater than 1.5 meters; when the distance between two adjacent I-shaped cross-section beams is 4 meters to 5 meters, the distance between two adjacent scaffolding steel pipe trusses 7 is not greater than 0.9 meters. The height of the scaffold steel pipe truss 7 is 10 cm to 12 cm smaller than the height of the I-shaped cross-section beam 1 . The distance between placing corrugated wood 8 on the horizontal scaffolding steel pipe 2 is 20 centimeters to 30 centimeters. The upper surface of the wooden template 5 is flush with the lower surface of the upper flange of the I-shaped cross-section beam 1 .

的Q235钢材，弹性模量2.06×10⁵N/mm²，强度215N/mm²。恒载标准值为：模板自重0.3kN/m²，150mm厚普通混凝土板3.6kN/m²；活载标准值为：施工人员及设备2.5kN/m²。承载能力验算时，模板上的荷载设计值为1.2×3.9+1.4×2.5＝8.18kN/m²，模板为跨度2.5m的单向板，取0.3m宽的板带，其最大弯曲应力为脚手架钢管桁架上受线荷载为8.18×2.5＝20.45kN/m，跨度3m，由水平脚手架钢管承受弯矩，最大应力 ${\mathrm{\&sigma;}}_2=\frac{1/{8\mathrm{ql}}^2}{W}=\frac{20.45\&times;{3000}^2}{8\&times;2.327\&times;{10}^7/200}=197.7N/{\mathrm{mm}}^2<[215N/{\mathrm{mm}}^2],$ 竖向脚手架钢管承受剪力，最大应力 ${\mathrm{\&sigma;}}_3=\frac{1/2\mathrm{ql}}{A}=\frac{20.45\&times;3000}{2\&times;289}=106.1N/{\mathrm{mm}}^2<[215N/{\mathrm{mm}}^2].$ 变形验算时，不计剪切变形，模板的荷载为0.3+3.6＝3.9kN/m²，模板最大挠度为 ${\mathrm{\&delta;}}_1=\frac{{5\mathrm{ql}}^4}{384\mathrm{EI}}=\frac{5\&times;3.9\&times;{10}^{-3}\&times;300\&times;{2500}^4}{384\&times;10000\&times;1.33\&times;{10}^7}=4.5\mathrm{mm}<l/250=8\mathrm{mm};$ 脚手架钢管桁架上受线荷载为3.9×2.5＝9.75kN/m，脚手架钢管桁架最大挠度 ${\mathrm{\&delta;}}_2=\frac{{5\mathrm{ql}}^4}{384\mathrm{EI}}=\frac{5\&times;9.75\&times;{3000}^4}{384\&times;2.06\&times;{10}^5\&times;2.327\&times;{10}^7}=2.1mm<l/250=12\mathrm{mm},$ 均满足要求。Example. There is a steel frame structure, the distance between the I-shaped cross-section beams is 3m, the height of the steel pipe truss of the scaffold is 0.4m, and the distance is 2.5m. The thickness of the wooden formwork is 18mm, the corrugated wood is 50mm×100mm, the distance between the corrugated wood is 300mm, the elastic modulus of the wood is 10000N/mm ² , and the bending strength is 13N/mm ² ;

Q235 steel, elastic modulus 2.06×10 ⁵ N/mm ² , strength 215N/mm ² . The dead load standard value is: self-weight of formwork 0.3kN/m ² , 150mm thick ordinary concrete slab 3.6kN/m ² ; live load standard value: construction personnel and equipment 2.5kN/m ² . When checking the bearing capacity, the design value of the load on the formwork is 1.2×3.9+1.4×2.5=8.18kN/m ² , the formwork is a one-way slab with a span of 2.5m, and the maximum bending stress is The line load on the scaffolding steel pipe truss is 8.18×2.5=20.45kN/m, the span is 3m, and the horizontal scaffolding steel pipe bears the bending moment, the maximum stress ${\mathrm{\&sigma;}}_2=\frac{1/{8\mathrm{ql}}^2}{W}=\frac{20.45\&times;{3000}^2}{8\&times;2.327\&times;{10}^7/200}=197.7N/{\mathrm{<figure-callout\; id="2"\; label="mm"\; filenames="H2009101540434E00011.png"\; state="\{\{state\}\}">mm</figure-callout>}}^2<[215N/{\mathrm{mm}}^2],$ The vertical scaffolding steel pipe bears the shear force, the maximum stress ${\mathrm{\&sigma;}}_3=\frac{1/2\mathrm{ql}}{A}=\frac{20.45\&times;3000}{2\&times;289}=106.1N/{\mathrm{<figure-callout\; id="2"\; label="mm"\; filenames="H2009101540434E00011.png"\; state="\{\{state\}\}">mm</figure-callout>}}^2<[215N/{\mathrm{mm}}^2].$ In the deformation check calculation, the shear deformation is not included, the load of the formwork is 0.3+3.6=3.9kN/m ² , and the maximum deflection of the formwork is ${\mathrm{\&delta;}}_1=\frac{{5\mathrm{<figure-callout\; id="4"\; label="ql"\; filenames="H2009101540434E00011.png,H2009101540434E00012.png"\; state="\{\{state\}\}">ql</figure-callout>}}^4}{384\mathrm{EI}}=\frac{5\&times;3.9\&times;{10}^{-3}\&times;300\&times;{2500}^4}{384\&times;10000\&times;1.33\&times;{10}^7}=4.5\mathrm{mm}<l/250=8\mathrm{mm};$ The line load on the scaffolding steel pipe truss is 3.9×2.5=9.75kN/m, and the maximum deflection of the scaffolding steel pipe truss ${\mathrm{\&delta;}}_2=\frac{{5\mathrm{<figure-callout\; id="4"\; label="ql"\; filenames="H2009101540434E00011.png,H2009101540434E00012.png"\; state="\{\{state\}\}">ql</figure-callout>}}^4}{384\mathrm{EI}}=\frac{5\&times;9.75\&times;{3000}^4}{384\&times;2.06\&times;{10}^5\&times;2.327\&times;{10}^7}=2.1mm<l/250=12\mathrm{mm},$ All meet the requirements.

Claims (4)

1. formwork bracing system that is used for the steel framed structure cast-in-place concrete floor is characterized in that: it comprises i shaped cross section beam (1), horizontal scaffold member steel pipe (2), vertical scaffolding steel pipe (3), steel tube fastener (4), wooden form (5), tie-rod steel pipe (6), stupefied wood (8); 2 horizontal scaffold member steel pipes (2) and many vertical scaffolding steel pipes (3) are connected to form scaffolding steel pipe truss (7) by steel tube fastener (4), the above scaffolding steel pipe truss of 2 Pin (7) are connected by steel tube fastener (4) with 2 above tie-rod steel pipes (6), scaffolding steel pipe truss (7) lower end places the bottom flange of i shaped cross section beam (1), the stupefied wood of scaffolding steel pipe truss (7) upper ends (8), stupefied wood (8) are gone up and are placed wooden form (5); Described two adjacent i shaped cross section beam (1) spacings are during less than 3 meters, and adjacent two Pin scaffolding steel pipe truss (7) spacings are not more than 2.5 meters; When two adjacent i shaped cross section beam (1) spacings were 3 meters to 4 meters, adjacent two Pin scaffolding steel pipe truss (7) spacings were not more than 1.5 meters; When two adjacent i shaped cross section beam (1) spacings were 4 meters to 5 meters, adjacent two Pin scaffolding steel pipe truss (7) spacings were not more than 0.9 meter.

2. a kind of formwork bracing system that is used for the steel framed structure cast-in-place concrete floor according to claim 1 is characterized in that the aspect ratio i shaped cross section beam (1) of described scaffolding steel pipe truss (7) is highly little 10 centimetres to 12 centimetres.

3. a kind of formwork bracing system that is used for the steel framed structure cast-in-place concrete floor according to claim 1 is characterized in that the last spacing of stupefied wood (8) of placing of described horizontal scaffold member steel pipe (2) is at 20 centimetres to 30 centimetres.

4. a kind of formwork bracing system that is used for the steel framed structure cast-in-place concrete floor according to claim 1 is characterized in that the upper surface of described wooden form (5) flushes with the soffit of i shaped cross section beam (1) top flange.

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