JPS60184811A - Manufacture of box girder, etc. - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] One rule applies to the method of manufacturing hollow concrete products.

Conventionally, to manufacture box girders for use in bridges, for example, the box girders are formed using fill-in inner frames.
In this case, the inner frame is embedded in the product and cannot be removed. For this reason, the inner frame must be manufactured to fit the total number of spaces in a large number of box girders, which increases the material costs and manufacturing costs for the inner frame, which only increases the cost of the product box girder and reduces the number of useful boxes. There was a problem that materials were wasted.

The present invention has been made in order to solve the above-mentioned problems.The present invention is made by dividing a mold into a hollow part, and by using an inner frame that can be filmed by shrinking, a hollow divided product is formed. It is an object of the present invention to provide a method for manufacturing a box girder in which the above-described conventional problems are solved by combining segmented products to form an integrated box girder.

Next, the formwork used in the method of manufacturing box girders and the like related to the present invention will be explained based on the drawings.

In FIG. 1 of the drawing, 1 is a γ1j digit A having a hollow part 2.
This is a formwork for manufacturing, which is formed by dividing into several parts so that the hollow part 2 described above is divided into a plurality of parts.Inside this formwork 1, as shown in Figure 1 of the drawings, a part from the main part a is formed. When the separated parts are combined with the main part a (!:M), the inner frame 3 is set to form a specified shape, and the product is formed by pouring concrete, and when the forming is finished, the inner frame 3 is separated. Main part;
The main part a is made to be smaller than the specified shape and then removed from the mold.

C is an operating means for the separation part in the inner frame 3 described above, and screws 6. 7 respectively,
When the links 4.4 and 5.5 are made to correspond to these screw pieces 6°7 as shown in FIG. 7, screw the right and left screws 9.10 of the operating shaft 8, 4 and 5° 5 are not shown in the drawing, but when setting them in the same direction, screws 9 and 10 should be in the same direction, and I) IJ operating shaft 8
When the is rotated in one direction, the links 4.4 and 5.5 rise and push the separation part onto the main part a, expanding the inner frame 3 into a predetermined shape, but the operating shaft 8 is rotated in the other direction. As a result, the links 4.4 and 5.5 fall down, and the separating portion is separated inward from the main portion a, causing the main portion a to contract as shown by the chain line in Fig. g of the drawing.

11, 11 are bent parts provided in the main part a to make it easier to expand and contract, and as shown in Figs. Either use a hinge that connects the parts so that they can be bent freely, or make a notch in the element IA of the main part a as shown in Figure S, so that the part can be bent from this part.

12, 12 is a locking part ti of the main part; l, which is a two-fold stay that bends when the main part a is contracted and extends when the main part a expands to hold the main part a in a specified shape. , wire, etc.

13, 13 are parts for holding the inner frame 3 in the formwork 1 (A is hung from the top of the formwork 1, and a tube 14 of the inner frame 3 expanded into a specified shape is attached to this part). 4, and then)
15, fixed by 15.

The above-mentioned formwork 1 is shown with a straight hollow part in the center, and the hollow part with a tapered end part is omitted, and the inner frame 3 forming this tapered hollow part is shown. If the outer side of the inner frame 3 is covered with a mold release layer and the concrete is isolated from the inner frame 3 by the mold release layer, the inner frame 3 can be removed from the mold even if it has the above-mentioned expansion/contraction structure.

16 indicates each product that has been molded separately.

With the PC strand that connects the
Insert it into the hole drilled as shown in the figure, tension it from both ends,
Each segmented product I to E is integrally formed to form a demolded hollow box girder A. During this connection, a shear pin (not shown in the drawing) is installed at the joint of the segmented product as is known. It is inserted.

Next, the manufacturing method and operation of the present invention using the above mold will be explained.

The inner frame 3 is housed in the formwork 1, and the inner frame 3 is operated by the operating means C.
Turn the operating shaft 8 in one direction to connect links 4.4 and 5.
5 is raised as shown in Figure 7 of the drawing, the separation part that was separated inward from the main part a and reduced the size of the main part a, as shown in Fig. It is pushed into the gap, fills the gap, and expands the main part a to form the specified inner frame shape. Therefore, this inner frame 3 is attached to the mounting tube 14, and 14 is attached to the holding portion H13.
, 13 -) 15 When stopped by 15, the inner frame 3 is suspended in the space within the formwork 1. In this state, concrete is poured into the formwork 1, and after pouring. When the mold can be removed after curing for a predetermined period of time, turn the operating shaft 8 to the other side and tilt down the links 4.4 and 5.5, and the separated part will be separated from the main part a as shown by the chain line in the drawing. As a result, the main portion a is deformed as shown in the figure, and the inner frame 3 is shunted from the specified shape. Then, if you pull the inner frame 3 sideways,
Since the inner frame 3 can be easily removed from the product to complete one hollow sectioned product C, 42 other sectioned products can be prepared in the same manner.

D and E are also manufactured, and after joining each of these classified products I to I by pushing a shear pin (not shown in the drawing) to the joint part, each classified product I to H is assembled as shown in Figure 7 of the drawing. f) Pass the C strand 16 through the hole penetrating the PC strand 16, and then tighten the PC strand 16 to form a box with a predetermined hollow space inside. Digit A
It completes the following.

In the method of the present invention, an inner frame is placed in a mold that is divided into sections in a hollow part, expanded to a specified shape, concrete is poured, and then the inner frame is shrunk and removed from the product. Since segmented products with hollow parts are molded and these segmented products are combined and integrated with reinforcing wires to form a box girder, by repeatedly using the inner frame, even a small number of inner frames can be used for a large number of box girders. Since it is sufficient just to use it, the material cost and production cost for the inner frame are reduced, which not only greatly contributes to reducing the cost of the product box girder, but also eliminates the waste of resources 1) due to burying.

In addition, this method involves separating a part from the main part as an inner frame,
We used a structure in which when this separated part is combined with one main part, it becomes a specified shape, and when separated, it becomes smaller than the specified shape,
After molding the product, by shrinking the inner frame and pulling it sideways, the product can be easily removed from the mold without damaging it, and it can also be quickly and accurately restored to the specified shape during mold assembly. The inner frame can be easily operated from outside without entering the inner frame, and has the unique effect of being extremely safe.

[Brief explanation of the drawing]

hwl "15; Fu11-To1-V++lRoyokyokukenfu4
->←-Ys1ml Sohi 4-kekF2 vertical side view. Figure 2 is a plan view of the same as above. Figure 3 is a front view showing the state of use on the same bridge as above. FIG. 1 is a longitudinal sectional front view of the manufacturing formwork same as above. FIG. 5 is a partial view showing another example of the bent portion of the main part of the inner frame in the same as above. Figure 4 is a cross-sectional plan view of the same formwork. FIG. 7 is a longitudinal sectional side view of the same as above. Fig. g is a longitudinal sectional front view showing a deformed state of the inner frame in the same as above. In the figure, A is a box girder, 1 is a formwork, 2 is a hollow part, 3 is an inner frame, a is a main part, b is a separation part, I9, B, C, 2, and H are classified products, 1
6 is a reinforcing wire.

Claims (1)

[Claims] A formwork for manufacturing a box girder or the like having a hollow part is formed into sections so that the hollow part is divided into a plurality of parts, and within each section of the formwork, a part of the frame is separated from the main part, and this divided layer is formed. The inner frame is set in a specified shape when the parts are combined with the main part, and the concrete Y is cast-molded. After forming, the separation part of the inner frame is separated inward from the main part, and this Accordingly, the main part is reduced to a smaller size than the specified shape, removed from the mold, and a sectioned product with a hollow section is made, and these sectioned products are connected and integrated with reinforcing wires to form a box girder with a hollow section. Manufacturing method for box girders, etc.