CN111042050A - Formwork construction process for bank protection retaining wall - Google Patents

Abstract

The invention discloses a formwork construction process for a revetment retaining wall, which sequentially comprises the following steps: (1) constructing a cushion layer; (2) constructing a retaining wall bottom plate; (3) constructing a cavity web plate; (4) a cavity top plate application step; (5) and constructing a wall formwork on the upper part of the retaining wall. The formwork construction process provided by the invention is applied to the construction of the bank protection retaining wall, can effectively shorten the construction period of the bank protection retaining wall and can ensure the construction quality.

Description

Formwork construction process for bank protection retaining wall

Technical Field

The invention relates to a port engineering technology, in particular to a construction technology of a bank protection retaining wall.

Background

In recent years, port engineering has been continuously developed, and high pile cap type bank protection structures are increasingly adopted. For example, some flood control walls adopt a front sheet pile high pile bearing platform type retaining wall structure.

When the retaining wall structure is constructed based on a conventional construction process at present, the problem of construction period process exists, so that the construction period of the whole project can be prolonged, subsequent projects can not be connected in order, and meanwhile, the construction cost of the whole project can be increased.

Therefore, the problem that the construction period of the existing retaining wall structure is too long is solved, and the problem that the field needs to solve urgently is provided.

Disclosure of Invention

Aiming at the problem of overlong construction period of the existing retaining wall structure, a new construction scheme is needed.

Therefore, the invention aims to provide a formwork construction process for a revetment and retaining wall, which is applied to retaining wall structure construction and can effectively improve the efficiency of retaining wall structure construction.

In order to achieve the purpose, the formwork construction process for the bank protection retaining wall provided by the invention sequentially comprises the following steps:

(1) constructing a cushion layer;

(2) constructing a retaining wall bottom plate;

(3) constructing a cavity web plate;

(4) constructing a cavity top plate;

(5) and constructing a wall formwork on the upper part of the retaining wall.

Further, the cushion layer construction step includes:

after the foundation pit is dug roughly, manually following the foundation pit to be leveled finely;

and after the foundation trench is excavated and leveled, the formwork is erected and concrete is poured.

Further, the retaining wall bottom plate construction step includes:

(1) measuring four corner points for placing a bottom plate edge line on the cushion layer;

(2) installing a pile core cage, and welding a top plate anchoring steel bar;

(3) cutting a steel bar distribution line on the bottom plate, and performing a steel bar binding process;

(4) after the steel bars are qualified, erecting an outer mold of the bottom plate, installing a water stop and installing a dowel bar;

(5) pouring concrete after the template is qualified;

(6) and after 24 hours, stripping the mould, watering and curing the concrete.

Further, the cavity web construction step comprises:

(1) manufacturing a web template, namely combining a phenolic aldehyde plate with rectangular steel to manufacture a template combined by shaped steel and wood;

(2) and (3) assembling the templates, wherein the water-facing web plates are assembled by adopting a straight external mold and a shaped upper chamfer template and a shaped lower chamfer template, and the pull screw rods on the lower layer are directly welded on the exposed reinforcing steel bars of the wall body.

Further, the construction of the cavity top plate mainly comprises the following steps:

(1) erecting steel pipe supports and adopting top plate supports

The steel pipes are used as vertical rods, the transverse spacing of the vertical rods is 733mm, the longitudinal spacing of the vertical rods is 900mm, and the vertical rods are 2335mm long according to the width of the cast-in-place top plate and are composed of 2000mm steel pipes and M36 x 500 jacking supports; the bottom layer of the vertical and horizontal pipe is 100mm away from the ground, and the rest spaces are 900 mm;

(2) laying a top plate template, placing 2 transverse jacking plates on each transverse jacking plate based on the upper support of the top plate keel

The steel pipe is used as a keel, 50mm 100mm 4000mm battens are longitudinally paved and fixed on the steel pipe keel; and finally, fixing the multilayer board on the batten.

Further, the construction of retaining wall upper portion wall form mainly includes:

(1) manufacturing a template, wherein the upper wall template is formed by combining a phenolic aldehyde plate and rectangular steel, and manufacturing a template combined by shaped steel and wood;

(2) the upper wall body formwork is assembled by adopting a straight piece outer formwork and a shaping variable slope formwork, and the lower layer of counter-pull screw rods are directly welded on the exposed reinforcing steel bars of the wall body.

(3) The template line adjustment adopts the straightness that hangs down of hammock control template after the template is assembled, adopts the straight line of slant flexible regulation steel pipe to adjust longitudinal line section, adjusts steel pipe upper end and bank side roof horizontal steel pipe and is connected, and the lower extreme is connected with the reinforcing bar of pre-buried on the surface course, forms a triangle-shaped, adjusts the length of steel pipe through the adjusting screw and adjusts the wall body template straightway.

The formwork construction process provided by the invention is applied to the construction of the bank protection retaining wall, can effectively shorten the construction period of the bank protection retaining wall and can ensure the construction quality.

Drawings

The invention is further described below in conjunction with the appended drawings and the detailed description.

FIG. 1 is a schematic diagram of the fabrication of a web form in an embodiment of the invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings.

In the construction process, the bank protection earthwork is excavated firstly, the construction of the upper structure of the bank protection is started, after the construction of the box-shaped top plate is completed, the lower beam of the construction platform is started, the front-edge earthwork is excavated after the construction of the lower beam is completed, and the slope protection is constructed when the elevation of-2 m is excavated.

By way of example, the excavation method herein includes:

1. the foundation pit earthwork excavation adopts natural slope excavation with the slope ratio of 1: 2.

2. The earthwork excavation is carried out by layering, segmenting, symmetrical, balancing and time-limited land excavation according to the principles of layering excavation, supporting before excavation and strictly over excavation.

3. The upper earthwork excavation adopts excavator construction, and the surface soil is grabbed off in a retreating type construction.

4. When the foundation pit is dug to be 30cm away from the designed pit bottom elevation, a foundation pit is leveled by adopting a manual soil digging and slope repairing method, the foundation pit is not over dug and disturbed, and after the foundation pit is dug to reach the designed pit bottom elevation, the concrete cushion is timely cast and tamped in blocks and sections so as to reduce the rebound of the soil body at the pit bottom.

And after the excavation is finished, entering a bank protection structure construction stage. The revetment structure is cast in blocks.

When the blocking pouring is carried out, the retaining wall is constructed in five steps according to the structural form of the retaining wall and the requirements of the construction progress.

The first step is as follows: constructing a cushion layer;

the cushion layer construction mainly comprises the following steps:

measuring and paying off → excavating a foundation pit → leveling the foundation pit → pouring a cushion layer → processing a pile head → pouring a pile core.

The second step is that: constructing a retaining wall bottom plate;

the construction of the retaining wall bottom plate mainly comprises the following steps:

measurement and paying-off → reinforcement binding → bottom plate formwork support → concrete pouring → form removal and maintenance.

The third step: constructing a cavity web plate;

the construction of the cavity web mainly comprises the following steps:

reinforcement → web form support → concrete pouring → form removal and maintenance.

The fourth step: constructing a top plate of the cavity;

here: the top plate construction of the cavity mainly comprises the following steps:

the framed bent erection → the top formwork laying → the reinforcement binding → the outer formwork erecting → the concrete pouring → the formwork removal and watering maintenance.

The fifth step: and constructing the retaining wall at the upper part of the retaining wall.

The construction of the retaining wall upper retaining wall mainly comprises the following steps:

reinforcement → side form erecting → concrete pouring → form removal and watering for maintenance.

On the basis, the construction flow of the template given in the example is mainly as follows.

And (I) constructing a cushion layer.

The cushion layer construction of this example mainly includes:

1. after the foundation pit is dug roughly, the fine leveling is followed manually, and the measurement is synchronously followed.

2. And after the foundation trench is excavated and leveled, the formwork is erected and concrete is poured.

And (II) constructing a retaining wall bottom plate.

This example carries out barricade bottom plate construction, mainly includes:

1. measuring four corner points for placing a bottom plate edge line on the cushion layer;

2. installing a pile core cage, and welding a top plate anchoring steel bar;

3. cutting a steel bar distribution line on the bottom plate, and performing a steel bar binding process;

4. after the steel bars are qualified, erecting an outer mold of the bottom plate, installing a water stop and installing a dowel bar;

5. pouring concrete after the template is qualified;

6. and after 24 hours, stripping the mould, watering and curing the concrete.

And (III) constructing the cavity web.

The construction of the cavity web plate is carried out in the embodiment, which mainly comprises the following steps:

1. making of shuttering

1) The web form was fabricated by joining 18mm phenolic boards 10 to 40 x 80 x 3 rectangular steel 20 to form a form of a profiled steel-wood joint (as shown in figure 1).

2) The single template is 1220mm wide and 2500mm high, each template is equipped with 4 vertical stupefied bones (40X 80X 3 rectangular steel), the distance (center distance) is 393mm, and 2 horizontal stupefied bones are adopted during assembly

The steel pipe is arranged through the length, the distance between the bottom layers is 501mm, the upward distance is 650mm, and the upward distance is 850 mm.

2. Assembly of formworks

1) The web plate on the upstream face is assembled by adopting a straight piece outer die and a shaped upper chamfer angle template and a shaped lower chamfer angle template, and the counter-pull screw rod on the lower layer is directly welded on the exposed reinforcing steel bar of the wall body, so that the upward floating of the template can be overcome except for the function of fixing the template. The upward screw rod is provided with a conical nut and an M14 screw rod with the L being 560mm to form a fixed-length counter-pulling screw rod which can play a counter-pulling role and a supporting role; and (4) screwing off the conical nut when the concrete is removed after pouring, and plugging the conical nut with the same grade of mortar.

2) The split screws of the middle web plate and the rear web plate only adopt a common M14 screw jacket

The threading pipe is convenient for the removal and the reuse of the screw rod. The remaining threading hole does not need to be plugged.

And (IV) constructing a cavity top plate.

This example carries out cavity roof construction, mainly includes:

1. erecting a steel pipe bracket;

1) roof support adopt

The steel pipes are used as vertical rods, the transverse spacing of the vertical rods is 733mm, the longitudinal spacing of the vertical rods is 900mm, the vertical rods are 2335mm long, and the steel pipes are composed of 2000mm steel pipes and M36 x 500 jacking supports. The bottom layer of the vertical and horizontal pipes is 100mm away from the ground, and the rest distances are 900 mm. The pipes are connected by right-angle fasteners, and the top plate is fixed in position, so that the cross brace rod is not required to be arranged in the longitudinal and transverse directions.

2) Laying a top plate template;

the top mold keel is based on the upper support, and 2 transverse top supports are placed on each channel

The steel pipe is used as a keel, 50mm 100mm 4000mm battens are longitudinally paved, and the steel pipe is fixed on the steel pipe keel by adopting iron wires. And finally, nailing the multilayer board with iron nails to the batten, wherein the thickness of the multilayer board is 18 mm.

And (V) constructing a wall formwork at the upper part of the retaining wall.

This example carries out the construction of barricade upper portion wall form, mainly includes:

1. making of shuttering

1) The upper wall formwork is made by combining 18mm phenolic boards with 40 × 80 × 3 rectangular steel, and the formwork combined by the shaped steel and the wood is manufactured.

2) The single template is 1220mm wide and 4700mm high, each template is equipped with 4 vertical stupefied bones (40 × 80 × 3 rectangular steel), the interval (center distance) is 393mm, and 2 horizontal stupefied bones are adopted during assembly

The steel pipes are arranged in a full-length mode, the bottom wails are 150mm away from the concrete surface, and then the distances are 600mm in sequence, and 8 paths are counted.

2. Assembly of formworks

1) The upper wall formwork is assembled by adopting a straight piece outer formwork and a shaping variable slope formwork, and the lower opposite-pulling screw rods are directly welded on the exposed reinforcing steel bars of the wall, so that the upward floating condition of the formwork can be overcome except for the function of fixing the formwork. The upward screw rod is a fixed-length counter-pulling screw rod consisting of an M14-40 conical nut and an M14 screw rod with the L being 560-360 mm, and the screw rod can play a counter-pulling effect and a supporting head effect; and (4) screwing off the conical nut when the concrete is removed after pouring, and plugging the conical nut with the same grade of mortar.

2) And adjusting the lines of the templates, controlling the verticality of the templates by adopting a hanging hammer after the templates are assembled, adjusting the straight line of a longitudinal line section by adopting an oblique telescopic adjusting steel pipe, connecting the upper end of the adjusting steel pipe with a horizontal steel pipe of a bank side top plate, and connecting the lower end of the adjusting steel pipe with a steel bar embedded on a surface layer to form a triangle. The length of the steel pipe is adjusted through the adjusting screw, so that the purpose of adjusting the straight line section of the wall body template is achieved.

The template construction of the embodiment also needs the following items:

1. before the template is used, cement paste adhered to the surface and the edges of the template must be removed completely, and the template with damaged edges and ribs and the warped and bent template are leveled and repaired, so that tight seams and smooth surface are ensured.

2. The surface of the template should be coated with a release agent, the template which is not coated with the adhesive mold agent is not used in the project, and the release agent is required to be uniformly coated and properly coated during coating so as to ensure that the appearance quality of the surfaces of the reinforcing steel bars and the concrete is not polluted.

3. The template has strict seam jointing requirement and is stuck by an adhesive tape to prevent the seam from leaking slurry.

5. The concrete side mould can be disassembled after the strength of the concrete can ensure that the surface and the edges of the concrete side mould are not damaged by disassembling the template.

Aiming at the construction process of the revetment structure and the construction scheme of the formwork, the embodiment further provides a corresponding concrete pouring scheme.

1. Pouring and vibrating concrete

1) The concrete placement is performed in sections determined in the overall arrangement.

2) The concrete is poured continuously, if necessary intermittently, the time is shortened, and the concrete of the next layer is poured before the concrete of the previous layer is set.

3) The total time of concrete transportation, pouring and intermittence should not exceed the specifications of the following table, and construction joints must be arranged when the specified time is exceeded.

4) When concrete is poured, the fast-inserting and slow-pulling mode is adopted. The quick insertion is to prevent the delamination and segregation between the surface concrete and the lower concrete caused by the compaction of the surface concrete; the slow drawing is to make the concrete to fill the cavity caused by the drawing of the vibrating rod.

5) When the concrete is poured in layers, the thickness of each layer of concrete is not more than 1.25 times of the length of the vibrating rod; the lower layer should be inserted about 50mm when the upper layer is vibrated to eliminate the seam between the two layers, and simultaneously, when the upper layer concrete is vibrated, it is performed before the lower layer concrete is initially set.

6) The vibration time of each insertion point needs to be controlled well, the insertion points are too short to be tamped easily, the concrete can be separated due to too long vibration time, and the concrete is particularly noticed, wherein the vibration time of each insertion point is generally 20-30S, the surface does not sink obviously any more when being horizontal, no air bubbles appear any more, and mortar is spread on the surface.

7) The insertion points of the vibrators need to be uniformly arranged, can move in a 'determinant' or 'staggered' order, and are not used in a mixed way, so that the problem of vibration leakage caused by disorder is avoided. The distance of each shift position should be no more than 1.5 times the action radius R of the vibrating rod. The action radius of the common vibrating rod is 300-400 mm.

8) In the concrete pouring process, slump tests are carried out in batches, and if the slump does not accord with the specification, the mixing proportion is properly adjusted.

9) In the concrete pouring process, the thickness of the concrete protective layer and the correctness of the position of the reinforcing steel bar are ensured. The original positions of the embedded part and the reserved hole can not be moved when the reinforcing steel bar is not trampled, and if deviations and displacements are found, the embedded part and the reserved hole can be corrected in time.

2. Curing of concrete

1) The concrete curing method is characterized in that a water spraying faucet is always prepared on site and water is continuously sprayed.

2) The natural condition that the average temperature is higher than +5 ℃ is utilized, the surface of the concrete is covered by a gunny bag and watered, so that the concrete keeps proper temperature and temperature condition required by the muddy water effect within a certain time.

3) The covering watering maintenance meets the following conditions

(1) The covering watering maintenance is carried out within 12 hours after the concrete pouring is finished.

(2) The watering curing time of the concrete is not less than 7 days for the concrete mixed by Portland cement and common Portland cement, and not less than 14 days for the concrete mixed with additives or having the impermeability requirement.

(3) The watering frequency is determined according to the condition that the surface of the concrete can be kept in a wet state.

(4) The water for curing the concrete should be the same as the mixing water.

(5) When the daily average temperature is lower than 5 deg.C, watering should not be carried out.

3. Pumping and casting of concrete

1) Requirements for the form

(1) Because the fluidity of the pumped concrete is large and the impact force of construction is large, when the template is designed, the template and the support are ensured to have enough strength, rigidity and stability according to the characteristic that the pressure of the pumped concrete on the template side is large.

(2) The distributing equipment is not collided or directly placed on the template, and the template and the bracket below the manual distributing rod are reinforced.

2) Requirement for reinforcing bars

When concrete is poured, attention should be paid to protect the reinforcing steel bars, and once the reinforcing steel bar framework deforms or displaces, the reinforcing steel bar framework should be corrected in time. Horizontal steel reinforcement of concrete slabs and block structures; enough rebar braces or steel brackets should be provided. Reinforcing measures should be taken for important nodes of the steel reinforcement framework.

3) Pumping of concrete

The operation of concrete pumps is a professional technical task. Safe use and operation, and strict implementation of the instructions and other relevant regulations. Meanwhile, special operation points are made according to the use instruction. The operators can be operated on duty after being trained and qualified.

4) Pouring of pump concrete

The pouring of the pumped concrete should plan the concrete pouring area in advance according to the conditions of the engineering structure characteristics, the plane shape and the geometric dimension, the concrete supply and pumping equipment capability, the labor force and management capability, the size of the surrounding field and the like.

5) Pouring sequence of pump concrete

(1) When concrete is conveyed by using the concrete conveying pipe, the concrete is poured from far to near.

(2) The concrete in the same area is continuously poured in a layered mode in the sequence of the vertical structure and the horizontal structure.

(3) When the construction joints are not allowed to be left, the concrete intermittent time between the areas and between the upper layer and the lower layer must not exceed the initial setting time of the concrete.

(4) After the lower layer concrete is initially set, the upper layer concrete is poured, and the treatment is carried out according to the stipulation of the reserved construction joint.

6) Distribution method of pump concrete

(1) When the vertical structure concrete is poured, the distance between the outlet of the distributing equipment and the inner side surface of the template is not less than 50mm, and the distributing equipment does not directly impact the inner side surface of the template and does not directly impact the steel reinforcement framework.

(2) When the horizontal structure concrete is poured, the material can not be continuously distributed at the same position, the material distribution is horizontally moved within the range of 2-3 m, and the material distribution is suitable to be perpendicular to the template.

(3) The concrete layering thickness is generally 300-500 mm. When the concrete casting thickness of the horizontal structure exceeds 500mm, the concrete casting thickness can be determined according to the following formula 1: 6-1: the 10-gradient layered pouring is carried out, and the upper layer concrete is covered with the lower layer concrete by more than 500mm in advance.

(4) When the pumping concrete is vibrated, the inserting distance of the vibrating rods is about 400mm generally, the vibrating time is 10s, and the pumping concrete is subjected to secondary re-vibration after 20-30 min.

(5) Corresponding technical measures are selected in advance for the position with the reserved hole and the embedded part with dense steel bars, so that smooth material distribution and vibration compaction are ensured. When concrete is poured, frequent observation is needed, and measures are needed to be taken immediately when the concrete is found to be not compact.

The template construction scheme provided by the embodiment can effectively shorten the construction period when being matched with the retaining wall structure for construction, and can effectively ensure the construction quality when being matched with the corresponding concrete pouring scheme.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (6)

1. The utility model provides a template construction technology for shore protection barricade which characterized in that includes in proper order:

(1) constructing a cushion layer;

(2) constructing a retaining wall bottom plate;

(3) constructing a cavity web plate;

(4) constructing a cavity top plate;

(5) and constructing a wall formwork on the upper part of the retaining wall.

2. The formwork construction process for a revetment retaining wall according to claim 1, wherein the bedding layer construction step comprises:

after the foundation pit is dug roughly, manually following the foundation pit to be leveled finely;

and after the foundation trench is excavated and leveled, the formwork is erected and concrete is poured.

3. The formwork construction process for a revetment retaining wall according to claim 1, wherein the retaining wall bottom plate construction step comprises:

(1) measuring four corner points for placing a bottom plate edge line on the cushion layer;

(2) installing a pile core cage, and welding a top plate anchoring steel bar;

(3) cutting a steel bar distribution line on the bottom plate, and performing a steel bar binding process;

(4) after the steel bars are qualified, erecting an outer mold of the bottom plate, installing a water stop and installing a dowel bar;

(5) pouring concrete after the template is qualified;

(6) and after 24 hours, stripping the mould, watering and curing the concrete.

4. The formwork construction process for a revetment retaining wall according to claim 1, wherein the cavity web construction step comprises:

(1) manufacturing a web template, namely combining a phenolic aldehyde plate with rectangular steel to manufacture a template combined by shaped steel and wood;

(2) and (3) assembling the templates, wherein the water-facing web plates are assembled by adopting a straight external mold and a shaped upper chamfer template and a shaped lower chamfer template, and the pull screw rods on the lower layer are directly welded on the exposed reinforcing steel bars of the wall body.

5. The formwork construction process for a revetment retaining wall according to claim 1, wherein the cavity roof construction mainly comprises:

(1) erecting steel pipe supports and adopting top plate supports

The steel pipes are used as vertical rods, the transverse spacing of the vertical rods is 733mm, the longitudinal spacing of the vertical rods is 900mm, and the vertical rods are 2335mm long according to the width of the cast-in-place top plate and are composed of 2000mm steel pipes and M36 x 500 jacking supports; the bottom layer of the vertical and horizontal pipe is 100mm away from the ground, and the rest spaces are 900 mm;

(2) laying a top plate template, placing 2 transverse jacking plates on each transverse jacking plate based on the upper support of the top plate keel

The steel pipe is used as a keel in the longitudinal directionPaving 50mm by 100mm by 4000mm battens, and fixing the battens on the steel pipe keels; and finally, fixing the multilayer board on the batten.

6. The formwork construction process for a revetment retaining wall according to claim 1, wherein the construction of the wall formwork on the upper portion of the retaining wall mainly comprises:

(1) manufacturing a template, wherein the upper wall template is formed by combining a phenolic aldehyde plate and rectangular steel, and manufacturing a template combined by shaped steel and wood;

(2) the upper wall body formwork is assembled by adopting a straight piece outer formwork and a shaping variable slope formwork, and the lower layer of counter-pull screw rods are directly welded on the exposed reinforcing steel bars of the wall body.

(3) The template line adjustment adopts the straightness that hangs down of hammock control template after the template is assembled, adopts the straight line of slant flexible regulation steel pipe to adjust longitudinal line section, adjusts steel pipe upper end and bank side roof horizontal steel pipe and is connected, and the lower extreme is connected with the reinforcing bar of pre-buried on the surface course, forms a triangle-shaped, adjusts the length of steel pipe through the adjusting screw and adjusts the wall body template straightway.

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