阅读说明：本技术 一种现浇混凝土小截面箱涵一次成型方法 (Cast-in-place concrete small-section box culvert one-step forming method ) 是由 吕建峰 常春 郭彦冬 张康博 常茂森 于 2021-05-10 设计创作，主要内容包括：本发明涉及工程建筑技术领域,具体涉及一种现浇混凝土小截面箱涵一次成型方法,包括：垫层浇筑,底板、侧墙、顶板钢筋绑扎,模板支设,混凝土浇筑,养护,模板拆除,基底垫层采用C20混凝土浇筑,垫层凝固达到设计要求后,进行底板、侧墙及顶板钢筋的绑扎,模板采用铝合金模板,现场拼装,模板下端通过膨胀螺栓与已经浇筑完成的垫层固定,模板支设完成后进行混凝土浇筑,先浇筑底板和部分侧墙,再浇筑剩余侧墙,最后浇筑顶板；浇筑完成后及时采用薄膜覆盖并进行养护；混凝土强度达到设计要求后进行模板拆除。本发明采用一次浇筑成型的施工方法,缩短了施工工期,避免了施工缝的留设,无接缝、错台等工程缺陷。(The invention relates to the technical field of engineering construction, in particular to a cast-in-place concrete small-section box culvert one-step forming method, which comprises the following steps: pouring a cushion layer, binding reinforcing steel bars of a bottom plate, side walls and a top plate, erecting a template, pouring concrete, maintaining, dismantling the template, pouring C20 concrete on a base cushion layer, binding the reinforcing steel bars of the bottom plate, the side walls and the top plate after the cushion layer is solidified to meet the design requirement, assembling the template on site by adopting an aluminum alloy template, fixing the lower end of the template with the poured cushion layer through expansion bolts, pouring concrete after the template is erected, pouring the bottom plate and part of the side walls firstly, pouring the rest of the side walls, and pouring the top plate finally; after pouring is finished, a film is adopted to cover in time and maintenance is carried out; and (4) dismantling the template after the concrete strength meets the design requirement. The invention adopts a one-time pouring forming construction method, shortens the construction period, and avoids the construction defects of construction joint reservation, no joint, slab staggering and the like.)

1. A cast-in-place concrete small-section box culvert one-step forming method is characterized by comprising the following steps: the method comprises the following steps:

s1, pouring a cushion layer; pouring the base cushion layer by using C20 concrete, and vibrating the concrete;

s2, binding the bottom plate, the side wall and the top plate steel bars, and binding the bottom plate, the side wall and the top plate steel bars after the cushion layer is solidified and meets the design requirement;

s3, template assembly; the template is an aluminum alloy template, screw holes are formed in the joints of the template, the template is assembled through the screw holes during field installation, the lower end of the template is fixed with a poured cushion layer through expansion bolts, the template is prevented from floating in the concrete pouring process, the aluminum alloy template comprises an inner mold and an outer mold, a supporting structure is arranged in the inner mold, and vibrating openings of 10cm to 10cm are reserved at the lower end of the inner mold every 90 cm;

s4, pouring concrete, namely pouring the bottom plate and part of the side walls, pouring the rest side walls, and pouring the top plate;

s5, after pouring is completed, covering with a film in time and maintaining;

and S6, removing the template after the concrete strength meets the design requirement.

2. The one-step forming method of the cast-in-place concrete small-section box culvert according to claim 1, characterized by comprising the following steps of: and in the step S1, the concrete vibrating time is 20-30S.

3. The one-step forming method of the cast-in-place concrete small-section box culvert according to claim 1, characterized by comprising the following steps of: and in the S3, a support rod is arranged between the lower end of the inner die and the cushion layer, and a split bolt is arranged between the side wall of the inner die and the side wall of the outer die.

4. The one-step forming method of the cast-in-place concrete small-section box culvert according to claim 1, characterized by comprising the following steps of: and in the step S4, the slump of the poured concrete is 150 +/-20 mm.

5. The one-step forming method of the cast-in-place concrete small-section box culvert according to claim 1, characterized by comprising the following steps of: in S4, the concrete is poured in layers, the pouring thickness of each layer is controlled to be about 30cm, and each layer is poured, the concrete is required to be vibrated fully, and compactness is guaranteed.

6. The one-step forming method of the cast-in-place concrete small-section box culvert according to claim 3, characterized by comprising the following steps of: the side wall of the aluminum alloy outer mold is connected with a bracket for keeping the structure of the outer mold stable.

Technical Field

The invention relates to the technical field of engineering construction, in particular to a method for forming a cast-in-place concrete small-section box culvert in one step.

Background

The construction procedure of the existing totally-enclosed box culvert concrete pouring is that a bottom plate and part of side walls are poured firstly, the rest part of side walls and the rest part of top plates are poured again after concrete is formed, so that the concrete pouring needs to be carried out twice on one section of box culvert, a large amount of time is consumed, waterproof treatment needs to be specially carried out on joints of the two pouring, and the hidden danger of water leakage exists in the subsequent use engineering.

Therefore, there is a need for improvements in the prior art.

Disclosure of Invention

In order to overcome the defects in the prior art, the method for forming the cast-in-place concrete box culvert with the small section at one time is provided.

In order to solve the technical problems, the invention adopts the technical scheme that:

a cast-in-place concrete small-section box culvert one-step forming method comprises the following steps:

s1, pouring a cushion layer; pouring the base cushion layer by using C20 concrete, and vibrating the concrete;

s2, binding steel bars of the bottom plate, the side wall and the top plate; after the cushion layer is solidified and meets the design requirement, binding the reinforcing steel bars of the bottom plate, the side wall and the top plate according to the design drawing;

s3, template assembly; the template is an aluminum alloy template, screw holes are formed in the joints of the template, the template is assembled through the screw holes during field installation, the lower end of the template is fixed with a poured cushion layer through expansion bolts, the template is prevented from floating in the concrete pouring process, the aluminum alloy template comprises an inner mold and an outer mold, a supporting structure is arranged in the inner mold, and vibrating openings of 10cm to 10cm are reserved at the lower end of the inner mold every 90 cm;

s4, pouring concrete, namely pouring the bottom plate and part of the side walls, pouring the rest side walls, and pouring the top plate;

s5, after pouring is completed, covering with a film in time and maintaining;

and S6, removing the template after the concrete strength meets the design requirement.

Further, in the step S1, the concrete vibrating time is 20 to 30 seconds.

Further, in S3, a support rod is disposed between the lower end of the inner mold and the cushion layer, and a split bolt is disposed between the side wall of the inner mold and the side wall of the outer mold.

Further, in the step S4, the slump of the cast concrete is 150 ± 20 mm.

Further, in S4, the concrete is poured in layers, the pouring thickness of each layer is controlled to be about 30cm, and each layer is poured, the concrete is required to be vibrated sufficiently, so as to ensure compactness.

Furthermore, the side wall of the aluminum alloy outer die is connected with a bracket for keeping the structure of the outer die stable.

Compared with the prior art, the invention has the following beneficial effects:

1. the construction process is simple, and construction period is shortened, and compared with the traditional pouring construction process, construction period is shortened by nearly half, and labor input is correspondingly reduced.

2. The engineering quality is improved, and the hidden danger of water leakage is reduced. In the traditional construction method, the two-time concrete pouring joint surface needs special treatment such as cleaning, water stopping sheet embedding by brushing cement slurry and the like, water leakage at the construction joint is prevented in the use process, the construction method adopting one-time pouring forming avoids the setting of the construction joint, the hidden danger of water leakage is reduced, and the engineering quality is improved.

3. During construction, one-time steel bar binding and formwork erecting are adopted, one-time pouring is completed, and the engineering defects of seams and staggered platforms generated during two-time pouring are avoided.

Drawings

The following will explain embodiments of the present invention in further detail through the accompanying drawings.

FIG. 1 is a schematic view of an aluminum alloy template structure.

In the figure: 1-template, 11-inner mold, 12-outer mold, 13-vibrating port, 14-support rod, 15-split bolt, 2-expansion bolt and 3-cushion layer.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example (b):

as shown in fig. 1, a method for one-step forming of a cast-in-place concrete box culvert with a small cross section comprises the following steps:

s1, pouring a cushion layer; pouring C20 concrete for the base cushion layer, and vibrating the concrete for 20-30 s;

s2, binding the bottom plate, the side wall and the top plate steel bars, and binding the bottom plate, the side wall and the top plate steel bars after the cushion layer is solidified and meets the design requirement;

s3, template assembly; the template 1 is an aluminum alloy template, a certain number of screw holes are reserved at the joint by utilizing the characteristics of high rigidity and plasticity of the aluminum alloy template during template design, the aluminum alloy template is assembled through the screw holes during field installation, the lower end of the template is fixed with a poured cushion layer 3 through expansion bolts 2, the template 1 is prevented from integrally floating upwards in the concrete pouring process, the aluminum alloy template comprises an inner mold 11 and an outer mold 12, a vibration port 13 of 10cm x 10cm is reserved at the lower end of the inner mold 11 every 90cm, the bottom plate concrete is conveniently vibrated during pouring of the bottom plate, the compactness of the bottom plate concrete is ensured, and the quality defects of honeycomb pitted surface and the like after template removal are avoided;

a support rod 14 is arranged between the lower end of the inner die 11 and the cushion layer 3, and a split bolt 15 is arranged between the side wall of the inner die 11 and the side wall of the outer die 12;

s4, pouring concrete, namely pouring the bottom plate and part of the side walls, pouring the rest side walls, and pouring the top plate; the pouring sequence and the vibrating method of the concrete are strictly controlled, the concrete is poured in layers, the pouring thickness of each layer is controlled to be about 30cm, and the concrete is required to be sufficiently vibrated and compact when each layer is poured.

S5, after pouring is completed, covering with a film in time and maintaining;

and S6, removing the template after the concrete strength meets the design requirement.

The slump of the poured concrete is 150 +/-20 mm.

The side wall of the aluminum alloy outer mold is connected with a bracket 4 for keeping the structure of the outer mold stable.

The method is suitable for concrete pouring of the small box culvert structure with the structure height less than 2.5m and the bottom plate thickness less than 300mm, and when the concrete is poured, the small box culvert structure is poured once, so that the construction period is shortened, the defects of construction quality such as construction joint reservation, joint, slab staggering and the like are avoided, and the application range is wide.

Although only the preferred embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art, and all changes are encompassed in the scope of the present invention.