JPH10266157A - Manufacture and manufacturing facility of steel concrete hybrid structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a facility, by which the occurrence of a crack at the time of the solidification of concrete can be prevented extremely, by properly controlling a temperature during concrete placing when a steel concrete hybrid structure is manufactured. SOLUTION: When concrete 5' is placed along a steel wall plate 2 for manufacturing a caisson for revetment, cooling water is circulated so that cooling water W on a steel-shell bottom section is sucked by a pump 12 and sprayed against the internal surface of the steel wall plate 2 by water spray devices 14. Accordingly, the generation of thermal stress based on the difference of the thermal conductivity of both the steel wall plate 2 and a concrete side wall 5 on the joint surfaces of the steel wall plate 2nd the concrete side wall 5 is prevented, and the generation of cracks at the time of the solidification of concrete is inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel-concrete hybrid structure in which concrete is cast on a steel plate surface of a steel plate structure, and is applied to a seawall caisson or the like.

[0002]

2. Description of the Related Art In recent years, steel-concrete hybrid structures have been widely used for floating piers and seawall construction, and FIG. 3 shows an example of a seawall caisson made of steel plate and concrete.

As shown in FIG. 3, a caisson 1 as a steel-concrete hybrid structure has a steel shell formed by a steel wall plate 2, a steel bottom plate 3 and the like, and a stud dove 8 and a reinforcing bar 9 are arranged on the steel shell. Is formed to form a concrete side wall 5 and a concrete bottom 6, and the inside is partitioned into small sections by a steel partition 4, and the upper part is closed by a concrete lid 7. Note that the symbol g in FIG.
Indicates land, m indicates the sea floor, and s indicates the sea level.

[0004] The caisson 1 as such a steel-concrete hybrid structure is manufactured in a factory or the like, transported to the site, and then placed on a foundation mound M previously built on the seabed m to prevent slipping of the asphalt mat 10. And the inside is filled with a filling material (sand) 11.

[0005]

As described above, this hybrid caisson 1 is a composite structure in which the surroundings of a steel shell are covered with concrete. Since the inner surface is a steel plate, it has excellent toughness, and the outer wall is covered with concrete and has corrosion resistance. On the other hand, there is a great difference in the thermal conductivity between steel and concrete (steel is 40 to 50 times that of concrete). Therefore, when caisson is made, concrete is poured around the steel shell. During the subsequent curing period, thermal stress is generated on the joint surface based on the difference in thermal conductivity (difference in elongation), and cracks may occur on the thin concrete side wall. It occurs especially in summer.

[0006] In summer, when the temperature is high, the setting of concrete is particularly rapid, and a cold joint is likely to occur at the casting joint. The temperature during casting of fresh concrete must be suppressed to 35 ° C or less.

Conventionally, however, no effective countermeasures have been taken against cracking of these concretes, and at best, the entirety of the concrete has been covered by sheet-sheeting in order to cure the concrete.

Accordingly, the present invention provides a method and equipment for producing a steel-concrete hybrid structure by appropriately controlling the temperature during concrete casting, thereby minimizing the occurrence of cracks during concrete solidification. The task is to provide

[0009]

In order to solve the above-mentioned problems, a method of manufacturing a steel-concrete hybrid structure according to the present invention comprises applying a concrete coating to a steel shell formed by a steel wall plate and a steel bottom plate. In the method of manufacturing a steel-concrete hybrid structure, cooling water is sprayed on the inner surface of the steel wall plate during concrete curing when the concrete wall is cast on the outer surface of the steel wall plate.

In the method of the present invention described above, the steel wall plate on which concrete is cast on the outer surface is sprayed with cooling water on the inner surface, so that the thermal stress on the joint surface between the steel wall plate and the concrete wall is increased. This suppresses the occurrence of cracks, thereby suppressing the occurrence of cracks during solidification of concrete.

Particularly in summer when the air temperature is high, the temperature at the joint surface can be suppressed to 35 ° C. or less by spraying the cooling water to prevent the occurrence of a cold joint at a concrete casting joint.

Further, the method of the present invention is characterized in that the spraying of the cooling water is performed by circulating the cooling water stored in the inner bottom of the steel shell, thereby continuously supplying the cooling water. The cooling water can be efficiently sprayed to the inner surface of the steel wall plate without making it unnecessary, which can contribute to an improvement in work efficiency.

Further, the manufacturing equipment of the present invention further includes a watering device for spraying cooling water on the inner surface of the steel wall plate during concrete curing when the concrete wall is cast on the outer surface of the steel wall plate. A sprinkler is connected to a water pump for sucking cooling water stored in the inner bottom of the steel shell.

As described above, when the water pump for sucking the cooling water stored in the inner bottom portion of the steel shell and the water sprinkler connected to the water pump and sprinkling water on the inner surface of the steel wall plate are provided, The temperature adjustment at the joint surface between the steel wall plate and the concrete wall to be cast along the outer surface of the steel wall plate will be performed appropriately, and the temperature rise at the joint surface will be more accurate especially during construction in summer. , Cracking during solidification of the concrete is prevented. That is, it is possible to sufficiently suppress the occurrence of cracks in the concrete wall due to the occurrence of thermal stress based on the difference in the thermal tradition rate (difference in elongation) between the steel wall plate and the curing concrete wall at the joint surface. Become like

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showing a method of manufacturing a steel-concrete hybrid structure according to an embodiment of the present invention; FIG. , FIG. 2
FIG. 2 is a sectional view taken along the line AA in FIG. 1.

The steel-concrete hybrid structure to which the manufacturing method and the manufacturing equipment of the present embodiment shown in FIGS. 1 and 2 is applied has the same structure as the seawall caisson shown in FIG. The steel shell formed by the plate 2 and the steel bottom plate 3 is coated with concrete.

That is, as shown in FIG. 2, a large number of stud dowels 8 are provided on the upper surface of the steel bottom plate 3, and a concrete bottom part 6 is cast so that these stud dowels 8 are buried. The concrete side wall 5 is formed by driving 5 ′.

In this embodiment, in particular, the outer surface of the steel wall plate 2 is
A method and equipment for casting a concrete side wall 5 using a formwork 15 is provided. As shown in FIGS. 1 and 2, a plurality of stud dowels 8 and a formwork are formed on the outer surface of a steel wall plate 2. When the concrete 5 ′ is driven into the concrete wall 15, and the concrete side wall 5 is formed, the cooling water W ′ is sprayed on the inner surface of the steel wall plate 2. That is,
By circulating the cooling water W stored in the inner bottom of the steel shell, the cooling water W ′ is sprayed on the inner surface of the steel wall plate 2.

In the present embodiment, as a facility for spraying the cooling water W 'described above, in the present embodiment, a sprinkler 14 for spraying the cooling water W' from the driving of the concrete 5 'to the curing of the concrete side wall 5 is provided. And piping to the sprinkler 14
Submersible pump 12 as a lifting pump connected via 13
The submersible pump 12 is installed in the water of the cooling water W stored in the inner bottom of the steel shell.

In the steel-concrete hybrid manufacturing method according to the present embodiment, the steel wall plate 2 on which the concrete 5 'is cast on the outer surface is sprayed with the cooling water W' on the inner surface, so that the steel wall plate 2 is formed. The generation of thermal stress at the joint surface with the concrete side wall 5 is suppressed, and thereby the generation of cracks during concrete solidification is suppressed.

Particularly in summer, when the temperature is high, the temperature at the joint surface can be suppressed to 35 ° C. or less by spraying the cooling water W ′ to prevent the occurrence of a cold joint at the concrete casting joint.

In the method of the present embodiment, since the cooling water W 'is sprayed by circulating the cooling water W stored in the inner bottom of the steel shell, continuous supply of the cooling water W is not required. In addition, the cooling water W 'can be efficiently sprayed on the inner surface of the steel wall plate 2, which can contribute to an improvement in work efficiency.

Further, in the manufacturing equipment of the present embodiment, the pump for sucking the cooling water W stored in the inner bottom of the steel shell is provided.
12 and a water sprinkling device 14 connected to the pump 12 to sprinkle water on the inner surface of the steel wall plate 2, so that the concrete to be cast along the steel wall plate 2 and the outer surface of the steel wall plate 2 is provided. Side wall 5
The temperature adjustment at the joint surface between the concrete side wall and the concrete side wall 5 can be appropriately performed, and the temperature rise at the joint surface during the construction work in summer can be appropriately suppressed. become. That is, the steel wall plate 2 and the concrete side wall 5 being cured at the joint surface
The thermal stress is generated based on the difference in thermal conductivity (difference in elongation) from the above, and the effect that cracks are generated in the concrete side wall 5 can be sufficiently suppressed.

[0024]

As described in detail above, according to the method and apparatus for manufacturing a steel-concrete hybrid structure of the present invention, the following effects can be obtained. (1) To prevent the occurrence of thermal stress at the joint surface between the steel wall plate and the concrete wall by spraying cooling water on the inner surface of the steel wall plate on which concrete is cast on the outer surface. As a result, the occurrence of cracks during solidification of the concrete is suppressed. (2) According to the above item (1), especially in summer when the temperature is high, the temperature at the joint surface is reduced to 35 ° C by spraying the cooling water.
By suppressing the following, it is possible to prevent the occurrence of cold joints at the concrete casting joint. (3) The spraying of the cooling water is performed by circulating the cooling water stored in the inner bottom of the steel shell, so that continuous replenishment of the cooling water becomes unnecessary, and cooling to the inner surface of the steel wall plate is performed. Water can be sprayed efficiently, which can contribute to improvement of work efficiency. (4) When a water pump for sucking cooling water stored in the inner bottom of the steel shell and a water sprinkler connected to the water pump and spraying water on the inner surface of the steel wall plate are provided, The temperature adjustment at the joint surface between the plate and the concrete wall that is to be cast alongside the outer surface of the steel wall plate will be performed appropriately, and the temperature rise at the joint surface will be accurately suppressed particularly during construction in summer. Therefore, cracking during solidification of the concrete is sufficiently prevented. That is, a thermal stress is generated based on a difference in thermal conductivity (difference in elongation) between the steel wall plate and the cured concrete wall at the joint surface, so that it is possible to suppress the occurrence of cracks in the concrete wall. .

[Brief description of the drawings]

FIG. 1 is a plan view showing a method of manufacturing a steel-concrete hybrid structure as one embodiment of the present invention and a state of spraying cooling water by a manufacturing facility.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a cross-sectional view of a seawall caisson as an example of a steel-concrete hybrid structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Revetment caisson 2 Steel wall board 3 Steel bottom plate 4 Steel bulkhead 5 Concrete side wall 5 'concrete 6 Concrete bottom 7 Concrete lid 8 Stud dowel 9 Reinforcing bar 10 Asphalt mat 11 Filling goods (sand) 12 Pumping pump (submersible pump) 13 Piping 14 Watering device 15 Formwork W, W 'Cooling water

Claims (3)

[Claims] 1. A method of manufacturing a steel-concrete hybrid structure comprising a steel shell formed of a steel wall plate and a steel bottom plate coated with concrete, wherein a concrete wall is cast along an outer surface of the steel wall plate. A method of manufacturing a steel-concrete hybrid structure, comprising spraying cooling water on the inner surface of the steel wall plate during the curing of the concrete. 2. The method of manufacturing a steel-concrete hybrid structure according to claim 1, wherein the spraying of the cooling water is performed by circulating the cooling water stored in an inner bottom portion of the steel shell. 3. A facility for producing a steel-concrete hybrid structure in which a steel shell formed by a steel wall plate and a steel bottom plate is coated with concrete, wherein a concrete wall is provided along an outer surface of the steel wall plate. It is equipped with a sprinkler for spraying cooling water on the inner surface of the steel wall plate during the curing of concrete when casting concrete, and the sprinkler is connected to a pump for sucking cooling water stored in the inner bottom of the steel shell. A facility for manufacturing a steel-concrete hybrid structure, characterized in that: