CN108130915B - Prefabricated assembled steel frame raft foundation post-casting strip formwork and construction method thereof - Google Patents

Abstract

The present invention discloses a prefabricated assembled steel frame raft foundation post-cast strip template and a construction method thereof. The template comprises a plurality of rectangular steel frame template units that are fixedly connected end to end. The steel frame template unit comprises an upper frame, a lower frame, and a water-stop steel plate arranged between the upper frame and the lower frame. The water-stop steel plates are two and are respectively welded between the long side surfaces of the upper frame and the long side surfaces of the lower frame. The two long side surfaces of the upper frame and the two long side surfaces of the lower frame are provided with mesh template surface layers. The tops of the two long side surfaces of the upper frame are respectively fixed with comb molds. The present invention changes the construction process of welding, tying, installing, and sealing the post-cast strip template on site after the steel bars at the raft post-cast strip position are tied, thereby advancing the start time of subsequent processes, accelerating the construction progress, and saving construction period. At the same time, the narrow construction space between the raft steel bars is changed, the construction conditions are improved, and the construction quality is guaranteed.

Description

Prefabricated assembled steel frame raft foundation post-casting strip formwork and construction method thereof

Technical Field

The invention belongs to the technical field of building construction, and in particular relates to a prefabricated assembled steel frame raft foundation post-casting strip template and a construction method thereof.

Background Art

In recent years, with the rapid development of my country's economy, there are more and more high-rise and super-high-rise buildings, and the proportion of large and super-thick raft foundations has gradually increased. In order to prevent the cast-in-place concrete structure from shrinking unevenly, eliminate or reduce the deformation of concrete due to temperature and humidity, and the adverse effects of structural settlement deformation on the building, post-cast strips should be set at appropriate positions on the foundation raft and the main structure, and the construction quality of the raft post-cast strip has become the key to the construction of the raft foundation.

The production and installation of traditional post-casting joint formwork and water-stop steel plate require on-site installation and welding after the reinforcement binding at the post-casting joint position of the raft slab is completed, which restricts the start time of subsequent processes and delays the progress of foundation construction. In addition, the welding work is performed on the raft slab reinforcement, and the welding quality is difficult to guarantee. The fixation is not reliable, which can easily lead to quality problems such as mold running and leakage. In the junction area of raft slabs of different thicknesses, the installation quality is more difficult to control and the construction efficiency is low.

Summary of the invention

The purpose of the present invention is to provide a prefabricated assembled steel frame raft foundation post-cast strip template which is simple in structure, easy to manufacture, convenient to install and can improve work efficiency, reduce operation difficulty, save construction costs and improve engineering benefits in order to solve the technical problems existing in the prior art.

Another object of the present invention is to provide a construction method for a prefabricated assembled steel frame raft foundation post-casting strip formwork.

In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a prefabricated assembled steel frame raft foundation post-cast strip formwork, comprising a plurality of rectangular steel frame formwork units fixedly connected at the head and tail, the steel frame formwork units comprising an upper frame, a lower frame and a waterstop steel plate arranged between the upper frame and the lower frame, the waterstop steel plates are two and are respectively welded between the long side surfaces of the upper frame and the long side surfaces of the lower frame, the two long side surfaces of the upper frame and the two long side surfaces of the lower frame are provided with a mesh formwork surface layer, and comb molds are respectively fixed on the tops of the two long side surfaces of the upper frame.

Furthermore, the long side surface of the upper frame includes two upper frame longitudinal cross bars arranged in parallel and a plurality of upper frame vertical bars installed between the two upper frame longitudinal cross bars, and a plurality of upper frame connecting rod components are arranged between the two long side surfaces of the upper frame, and each group of upper frame connecting rod components includes two upper frame transverse cross bars arranged in parallel up and down.

Furthermore, two upper frame diagonal braces are arranged crosswise with each other between the two upper frame transverse cross bars of the upper frame connecting rod member.

Furthermore, the upper frame connecting rod components are in three groups and are respectively arranged at both ends and the middle of the long side surfaces of the upper frame.

Furthermore, the long side surface of the lower frame includes two lower frame longitudinal cross bars arranged in parallel and a plurality of lower frame vertical bars installed between the two lower frame longitudinal cross bars, and a plurality of groups of lower frame connecting rod components are arranged between the two long side surfaces of the lower frame, and each group of lower frame connecting rod components includes two lower frame transverse cross bars arranged in parallel up and down.

Furthermore, two lower frame diagonal braces are arranged crosswise with each other between the two lower frame transverse cross bars of the lower frame connecting rod member.

Furthermore, the lower frame connecting rod components are in three groups and are respectively arranged at both ends and the middle of the long side surfaces of the lower frame.

Furthermore, the mesh template surface layer is a combination structure of steel plate mesh and steel wire mesh or a quick-closing mesh.

Furthermore, the comb mold includes a beam, and a plurality of grooves are evenly formed on the bottom of the beam.

A construction method for a prefabricated assembled steel frame raft foundation post-casting strip formwork comprises the following steps:

A. Construction preparation: The construction technicians shall calculate the dimensions of each part of the post-casting strip in detail according to the raft construction drawings, design the dimensions of the prefabricated assembled steel frame raft foundation post-casting strip template, draw the processing drawings, and make the assembled steel frame raft foundation post-casting strip template;

B. Construction layout: lay out the position line of the post-casting strip according to the design drawings;

C. Construction of cushion layer, waterproof layer and protective layer: Organize the construction of cushion layer, waterproof layer and protective layer according to the schedule requirements, and install additional steel bars for post-casting belts at the same time;

D. Organize the installation and binding of the lower layer steel mesh of the raft slab: start from the position of the post-casting belt to tie and install the lower layer steel bars of the raft slab, and then expand to other areas;

E. Install the post-casting strip template: After the lower layer of steel mesh at the post-casting strip is tied and installed, the post-casting strip template is installed immediately. Since the post-casting strip template is prefabricated in sections, a tower crane is used to hoist the steel frame template unit to the post-casting strip position, and then electric welding is used to weld each steel frame template unit into a whole, and the water stop steel plate is welded through at the same time;

F. Arrange the mesh formwork surface layer: After welding the steel frame formwork units into a whole, arrange and seal the mesh formwork surface layer, especially the joints of the steel frame formwork units and the bottom of the lower steel bars of the raft slab should be sealed tightly, extend the mesh formwork surface layer downward to overlap with the raft slab cushion layer, and then use fine stone concrete with a higher strength than the raft slab concrete for sealing;

G. Binding of upper reinforcement of raft slab: After the binding of lower reinforcement of raft slab is completed, the upper reinforcement mesh of raft slab shall be immediately bound. At this time, the post-casting strip formwork of assembled reinforcement frame raft slab foundation can be used as the support of upper reinforcement of raft slab, and there is no need to set up a separate support at this position;

H. Install the comb mold: After the upper steel mesh of the raft is tied, cut the lower part of the beam into a comb shape according to the diameter and spacing of the steel bars, and install it on the upper part of the post-casting strip to seal the surface concrete of the raft. The height of the comb mold should be slightly larger than the thickness of the raft steel bar protective layer;

I. Pouring concrete: After the raft slab reinforcement is tied and accepted by all parties, concrete can be poured.

The present invention has the following beneficial effects relative to the prior art: the prefabricated assembled steel frame raft foundation post-casting strip template of the present invention comprises a plurality of rectangular steel frame template units fixedly connected at the head and tail, each steel frame template unit comprises an upper frame, a lower frame and a water-stop steel plate arranged between the upper frame and the lower frame, a certain number of steel frame template units can be processed in advance outside the site according to the design size of the post-casting strip, and the post-casting strip template is installed while tying the raft steel bars, which changes the construction process of welding, tying, installing and blocking the post-casting strip template on site after the steel bars are tied at the raft post-casting strip position, promotes the start time of the subsequent process to be advanced, speeds up the construction progress and saves the construction period. At the same time, since it is prefabricated outside the site, there is no need to drill into the raft steel cage for welding, installation, tying and other work, which changes the narrow construction space between the raft steel bars, improves the construction conditions and ensures the construction quality. In addition, the steel frame has a certain bearing capacity, rigidity and stability, and can serve as a support for the upper steel bars of some rafts, which saves costs and improves the safety of construction. The invention has a simple structure, is easy to manufacture and install, reduces the difficulty of operation, improves work efficiency, saves construction costs, and improves engineering benefits.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic diagram of the structure of the present invention;

FIG2 is a schematic structural diagram of a steel frame template unit of the present invention;

FIG3 is a schematic structural diagram of an upper frame of the present invention;

FIG. 4 is a schematic structural diagram of the lower frame of the present invention.

The meanings of the reference numerals in the accompanying drawings of the present invention are as follows: 1. upper frame; 2. lower frame; 3. water-stop steel plate; 4. mesh formwork surface layer; 5. comb mold; 101. longitudinal cross bar of upper frame; 102. transverse cross bar of upper frame; 103. vertical pole of upper frame; 104. diagonal brace of upper frame; 201. longitudinal cross bar of lower frame; 202. transverse cross bar of lower frame; 203. vertical pole of lower frame; 204. diagonal brace of lower frame.

DETAILED DESCRIPTION

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1-2, a prefabricated assembled steel frame raft foundation post-cast strip formwork includes a plurality of rectangular steel frame formwork units fixedly connected end to end, the steel frame formwork units include an upper frame 1, a lower frame 2 and a waterstop steel plate 3 arranged between the upper frame 1 and the lower frame 2, there are two waterstop steel plates 3 and they are respectively welded between the long side surfaces of the upper frame 1 and the long side surfaces of the lower frame 2, mesh formwork surface layers 4 are provided on the two long side surfaces of the upper frame 1 and the two long side surfaces of the lower frame 2, the mesh formwork surface layers 4 are a combination structure of steel plate mesh and steel wire mesh or a quick-closing mesh, which is closed on the outer surfaces of the two long side surfaces of the upper frame 1 and the two long side surfaces of the lower frame 2, plays a role in blocking concrete and ensuring that the post-cast strip is formed as designed, comb molds 5 are respectively fixed to the tops of the two long side surfaces of the upper frame 1, the comb molds 5 include beams, and a plurality of grooves are evenly opened on the bottom of the beams.

As shown in Figure 3, the long side of the upper frame 1 includes two upper frame longitudinal cross bars 101 arranged in parallel and multiple upper frame vertical bars 103 installed between the two upper frame longitudinal cross bars 101. Multiple groups of upper frame connecting rod components are arranged between the two long side surfaces of the upper frame 1. The upper frame connecting rod components are three groups and are respectively arranged at the two ends and the middle of the long side surfaces of the upper frame 1. Each group of upper frame connecting rod components includes two upper frame transverse cross bars 102 arranged in parallel up and down. Two upper frame diagonal braces 104 arranged crosswise with each other are arranged between the two upper frame transverse cross bars 102 of the upper frame connecting rod components.

As shown in Figure 4, the long side of the lower frame 2 includes two lower frame longitudinal cross bars 201 arranged in parallel and multiple lower frame vertical bars 203 installed between the two lower frame longitudinal cross bars 201. Multiple groups of lower frame connecting rod components are arranged between the two long side surfaces of the lower frame 2. The lower frame connecting rod components are three groups and are respectively arranged at the two ends and the middle of the long side surfaces of the lower frame 2. Each group of lower frame connecting rod components includes two lower frame transverse cross bars 202 arranged in parallel up and down. Two lower frame diagonal braces 204 arranged crosswise with each other are arranged between the two lower frame transverse cross bars 202 of the lower frame connecting rod components.

The following steps are included in the construction of the prefabricated assembled steel frame raft foundation post-casting strip formwork:

A. Construction preparation: The construction technicians shall calculate the dimensions of each part of the post-casting strip in detail according to the raft construction drawings, design the dimensions of the prefabricated assembled steel frame raft foundation post-casting strip template, draw the processing drawings, and make the assembled steel frame raft foundation post-casting strip template.

B. Construction layout: Lay out the position line of the post-cast joint according to the design drawings.

C. Construction of cushion layer, waterproof layer and protective layer: Organize the construction of cushion layer, waterproof layer and protective layer according to the schedule requirements, and install and tie additional steel bars for post-cast joints at the same time.

D. Organize the installation and binding of the lower layer of steel mesh of the raft slab: start from the position of the post-casting zone to bind and install the lower layer of steel bars of the raft slab, and then expand to other areas.

E. Install the post-casting strip formwork: After the lower layer of steel mesh at the post-casting strip position is tied and installed, the post-casting strip formwork is installed immediately. Since the post-casting strip formwork is prefabricated in sections, a tower crane is used to lift the steel frame formwork unit to the post-casting strip position, and then electric welding is used to weld each steel frame formwork unit into a whole, and at the same time, the waterstop steel plate 3 is welded through.

F. Arrange the mesh formwork surface layer: After welding the steel frame formwork units into a whole, arrange and seal the mesh formwork surface layer 4, especially the joints of the steel frame formwork units and the bottom of the lower steel bars of the raft slab must be tightly sealed, extend the mesh formwork surface layer 4 downward to overlap with the raft slab cushion layer, and then use fine stone concrete with a strength one grade higher than that of the raft slab concrete for sealing.

G. Binding of the upper steel bars of the raft slab: After the binding of the lower steel bars of the raft slab is completed, the upper steel mesh of the raft slab shall be immediately bound. At this time, the post-cast strip formwork of the assembled steel frame raft slab foundation can be used as a support for the upper steel bars of the raft slab, and there is no need to set up a separate support at this position.

H. Install the comb mold: After the upper steel mesh of the raft slab is tied, cut the lower part of the beam into a comb shape according to the diameter of the steel bars and the spacing between the steel bars to make a comb mold 5, which is installed on the upper part of the post-casting zone to seal the surface concrete of the raft slab. The height of the comb mold 5 should be slightly larger than the thickness of the raft slab steel bar protective layer.

I. Pouring concrete: After the raft slab reinforcement is tied and accepted by all parties, concrete can be poured.

Claims (5)

1. The utility model provides a prefabricated assembled steel bar framework raft foundation post-cast strip template which characterized in that: including a plurality of cuboid reinforcing bar frame template units of end-to-end fixed connection, reinforcing bar frame template unit includes frame (1), underframe (2) and sets up sealing steel sheet (3) between frame (1) and underframe (2) in the top, sealing steel sheet (3) are two and fix respectively between frame (1) long limit side and underframe (2) long limit side in the top, all be equipped with netted template surface course (4) on two long limit sides of frame (1) and the two long limit sides of underframe (2), frame (1) two long limit side tops are fixed with comb submodule (5) respectively in the top, frame (1) long limit side includes parallel arrangement's two upper frame longitudinal cross bar (101) and installs many upper frame pole (103) between two upper frame longitudinal cross bar (101), be equipped with multiunit upper frame connecting rod member and every group upper frame connecting rod member and including two upper and lower parallel arrangement's upper frame transverse bar (102) between two long limit sides of upper frame (1), two upper frame longitudinal cross bar (201) are equipped with between two longitudinal cross bar (201) of two upper frame longitudinal cross bar (102), a plurality of groups of lower frame connecting rod members are arranged between two long side surfaces of the lower frame (2), each group of lower frame connecting rod members comprises two lower frame transverse cross rods (202) which are arranged in parallel up and down, and two lower frame diagonal braces (204) which are arranged in a mutually crossing manner are arranged between the two lower frame transverse cross rods (202) of the lower frame connecting rod members; the construction method comprises the following steps:

A. And (3) preparation of construction: calculating the size of each part of the post-cast strip in detail by construction technicians according to raft construction drawings, designing the size of a post-cast strip template of a prefabricated reinforced frame raft foundation, drawing processing drawings, and manufacturing the post-cast strip template of the prefabricated reinforced frame raft foundation;

B. And (3) construction paying-off: discharging a position line of the post-cast strip according to the design drawing;

C. And (3) cushion layer, waterproof layer and protective layer construction: organizing the construction of the cushion layer, the waterproof layer and the protective layer according to the schedule requirement, and simultaneously installing and binding additional steel bars of the post-pouring belt;

D. installing and binding a reinforcing mesh at the lower layer of the tissue raft plate: firstly binding and installing raft lower layer steel bars from the post-pouring belt position, and then expanding to other areas;

E. Installing a post-cast strip template: immediately installing a post-pouring strip template after binding and installing a lower layer reinforcing steel bar net at the post-pouring strip position, hoisting reinforcing steel bar frame template units to the post-pouring strip position by adopting a tower crane due to the adoption of segmented prefabrication, welding all reinforcing steel bar frame template units into a whole by adopting electric welding, and simultaneously welding a water stop steel plate (3) through;

F. Finishing a reticular template surface layer: after welding the reinforcing steel bar framework template units into a whole, arranging and plugging the net-shaped template surface layer (4), tightly plugging the joints of the reinforcing steel bar framework template units and the bottoms of the reinforcing steel bars at the lower layer of the raft, downwards extending the net-shaped template surface layer (4), overlapping with the raft cushion layer, and plugging by adopting fine stone concrete with a grade higher than the strength of the raft concrete;

G. Binding upper layer steel bars of the raft plates: immediately binding the upper layer steel bar net of the raft after the binding of the lower layer steel bars of the raft is completed, and taking the post-cast strip template of the raft foundation of the assembled steel bar frame as a bracket of the upper layer steel bars of the raft at the moment, wherein the bracket is not required to be arranged at the position separately;

H. Installing a comb sub-die: after binding of the upper layer reinforcing steel bar net of the raft, cutting the lower part of the balk wood into a comb shape according to the diameter of the reinforcing steel bars and the size of the spacing between the reinforcing steel bars to obtain comb dies (5), and installing the comb dies (5) at the upper part of the post-cast strip for plugging the surface layer concrete of the raft, wherein the height of the comb dies (5) is slightly larger than the thickness of the reinforcing steel bar protection layer of the raft;

I. Pouring concrete: and after the raft steel bars are bound, pouring concrete after being accepted by all parties.

2. The prefabricated rebar framework raft foundation post-cast strip template of claim 1, wherein: the upper frame connecting rod members are three groups and are respectively arranged at two ends and the middle of the long side surface of the upper frame (1).

3. The prefabricated rebar framework raft foundation post-cast strip template of claim 1, wherein: the lower frame connecting rod members are three groups and are respectively arranged at the two ends and the middle part of the long side surface of the lower frame (2).

4. The prefabricated rebar framework raft foundation post-cast strip template of claim 1, wherein: the reticular template surface layer (4) is a combined structure of a steel plate net and a steel wire net or a fast and easy closing net.

5. The prefabricated rebar framework raft foundation post-cast strip template of claim 1, wherein: the comb die (5) comprises wood beams, and a plurality of grooves are uniformly formed in the bottom of the wood beams.