JPH0718235B2 - Concrete placing method and apparatus - Google Patents

Description

The present invention relates to a concrete pouring method and apparatus.

[Prior Art and its Problems] In general, a concrete building, as shown in FIG.
Concrete members such as pillars are spliced in the longitudinal direction, and mass concrete such as dams are spliced in blocks as shown in FIG. 7.

As described above, the temperature of the poured concrete rises due to the heat of hydration of the cement, and the concrete expands and is elastically deformed by compression, and also elastically deformed by tension over time. Then, if there is an external restraint due to the foundation or the concrete portion that has been cast in advance, tensile strain occurs and cracks occur.

After the concrete is placed, the internal temperature of the concrete is high, but the temperature of the concrete near the formwork does not rise to a high temperature due to the cooling from the surface of the formwork. Since the surfaces of both sides of the concrete are rapidly cooled, the above-mentioned temperature difference becomes more severe and cracks are likely to occur.

In order to solve these problems, conventionally, there has been a method of dividing the concrete member in the longitudinal direction of the concrete member so that cracking does not occur, and joining the pieces, or using a heat insulating form to reduce the temperature gradient inside the concrete.

However, the above-mentioned divided placing method has a problem in strength due to splicing, and the method using an adiabatic formwork may cause a temperature gradient if the formwork is dismantled early, so that the concrete temperature is sufficiently low. Until then, there was a problem that it had to be left for a long time.

[Object of the Invention] The present invention has been made in order to solve the above-mentioned conventional problems, and an object of the present invention is to prevent temperature cracking of concrete and to construct a highly durable concrete structure. It is to provide a concrete pouring method and apparatus capable of placing concrete.

[Structure of the Invention] In the concrete pouring method of the present invention, the pouring space between the molds is divided into a plurality of divided pouring spaces in a direction parallel to the molds, and a time difference is generated in each divided pouring space. It is characterized by placing concrete and placing concrete, and placing concrete by shifting the joining surfaces of the above-mentioned divided placing spaces relative to each other, and changing the adhesion state of each joining surface. It is a feature. Further, the concrete pouring device of the present invention is characterized in that an embedded form is installed between the forms in a direction parallel to the form to form a plurality of divided placement spaces, and the embedded form is used. Is a lath form frame.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a formwork between which a casting space 2 is formed. The casting space 2 is composed of a lath mold 3 in parallel with the mold 1 to form a divided casting space 2 '.

The lath form 3 is an embedded form that is not removed after the concrete is poured. The embedded formwork may be a mesh or the like. When placing concrete, first, one of the divided placing spaces 2'is first driven, and then the other of the divided placing spaces 2'is applied after a certain time lag.

FIG. 2 shows another embodiment in which two rows of lath molds 3 form three rows of divided casting spaces 2 '. In this case, first, the concrete is first cast into the central divided casting space 2 ', and after a certain period of time, the divided casting spaces 2'on both sides are post-cast. As described above, when the divided casting spaces 2'are placed with a time lag, the temperature rise is suppressed as compared with A in the case of simultaneous placement, as well as the pre-strike as shown in FIG. The temperature decrease of the concrete B is smoothed by the post-casting concrete C, and as a result, cracks (marked by x) due to tensile strain are eliminated.

Further, as shown in FIG. 4, when the casting space 2 is divided into five rows of divided casting spaces 2'by four lath molds 3, each divided casting space 2'is It is divided into alternate groups X and Y, and one group X is hit first, and then the other group Y is hit later.

Furthermore, as shown in FIG. 5, it is advisable to shift the joining surfaces 4'of the respective divided placing parts 4, in which case the lath form 3 near the joining surface 4'and the concrete. Control adhesion and keep it weak.

[Effects of the Invention] In a casting space between molds, an embedded mold is installed in a direction parallel to the molds, the casting space is divided into a plurality of divided casting spaces, and each divided casting is made. Since the concrete is poured with a time lag in the space, not only the temperature rise is suppressed compared to simultaneous pouring, but the temperature drop of the first-cast concrete is smoothed by the second-cast concrete and the temperature crack of the concrete is cracked. Is effectively prevented, and as a result, a durable concrete structure can be constructed.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a mold for carrying out the method of the present invention, FIG. 2 is a perspective view showing another embodiment, FIG. 3 is a graph showing the effect of time-staggered casting, and FIG. Is an explanatory view of yet another embodiment, FIG. 5 is a drawing for explaining a splicing surface and adhesion control, and FIGS. 6 and 7 are drawings for explaining a conventional concrete pouring method. 1 ... formwork, 2 ... casting space, 2 '... divided casting space,
3 ... Lath form frame, 4 ... Separate placement section, 4 '... Lacing surface.

Claims (5)

[Claims] 1. A method of dividing a casting space between molds into a plurality of divided casting spaces in a direction parallel to the molds, and placing concrete with a time lag in each divided casting space. Characteristic concrete pouring method. 2. The concrete pouring method according to claim 1, wherein the pouring surfaces of the divided pouring spaces are shifted from each other to pour the concrete. 3. The concrete pouring method according to claim 2, wherein the adhering state of each joining surface is changed. 4. A concrete pouring device, characterized in that an embedded mold is installed between the molds in a direction parallel to it to form a plurality of divided pouring spaces. 5. The concrete pouring device according to claim 4, wherein the embedded formwork is a lath formwork.