JPS63277306A - Execution of floor panel joint of precast concreat beam - 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 [Industrial Field of Application] The present invention relates to a method for constructing slab joints in precast concrete girders.

In more detail, without using formwork or scaffolding,
We also describe a method for rapidly constructing watertight joints in precast concrete girder deck slabs without the need for demolding, such as lock shades installed on roads where there is a risk of falling rocks or collapses, to block traffic for long periods of time. The purpose is to provide an optimal construction method for constructing floor slab joints at work sites where it is impossible to do so.

[Conventional technology]

The construction of rock shades in mountainous areas will be explained below as an example.

Roads along the slopes of mountains, streams, or rivers are often at risk of falling rocks or collapses, and various measures are being taken to prevent these risks.

One such measure is to construct structures (rock shades) that cover roads.

Such structures are (b) Requires sufficient strength to be safe against falling rocks, etc.

(b) Since the road is located in a mountainous area, there are usually no outside roads, so when constructing the road, it is necessary to avoid blocking traffic, or even if it is blocked, it must be limited to a minimum period of time.

(c) Earth and sand will be placed on the roof of the structure as a cushioning material against falling rocks, so muddy water will not flow into the rock shade due to rainwater seepage.

A watertight slab must be formed.

(d) Transportation of materials to the rock shade construction site and on-site work machines will be restricted.

There are significant structural and construction constraints.

As a structure that satisfies the above constraints, the award goes to the rock shade, which is constructed by constructing precast concrete girders that are strong, have a small cross section, and are easy to assemble, and are constructed in a row across the road so as to cover it. has been done.

However, even when such structures are constructed using precast members, conventionally, when constructing the joints of the deck slabs of precast concrete girders, a formwork made of plywood or the like is supported from below, and the work is carried out within this formwork. Concrete or mortar was poured and the formwork was removed after it had hardened.

Therefore, in order to carry out construction according to a work procedure that minimizes traffic interruption, it is necessary to divide the joint construction into small sections and construct them in a short time, or to carry out work at night, which requires a huge amount of time and effort. It was inevitable.

[Problem that the invention seeks to solve]

The object of the present invention is to provide a construction method for floor slab joints that is most suitable for such cases.

In other words, construction can be carried out using only a minimum of simple scaffolding, traffic interruptions or restrictions can be kept to a minimum, scaffolding etc. can be removed a short time after joint construction, and the need for demolding is omitted. In addition, it is possible to easily form joints in a waterproof structure.

[Means for solving problems]

The present invention consists of the following steps.

■ A precast joint covering material is made in advance by connecting two elongated blocks that cover both surfaces of the joints of the floor slab with reinforcing bars embedded in the joints. This joint covering material is made by forming book blocks parallel to each other with a distance slightly larger than the thickness of the floor slab.In order to make this joint covering material easy to handle, the length of the blocks is set to 0. It is advisable to form it to about .5m to 1m.

■ The reinforcing bars of the joint covering material enter the joint, and the
Insert the book block into the joint from the end face of the slab (both ends of the girder) so that it covers the surface of the joint of the slab.

■ Place mortar in the gap between the two blocks of joint covering material and the floor slab and in the joint. In this case, seal the mortar to prevent it from leaking.

■ By placing joint mortar, the floor slab and joint covering material are integrated through the mortar and reinforcing bars, so if they are left in place, the waterproof joint is completed.

[Effect]

According to the method of the present invention, a precast joint covering material may be attached to the joint portion instead of the joint form, and joint mortar may be applied, thereby eliminating the need for a form support material and the need for demolding.

Therefore, construction can be performed quickly and labor-savingly, and joint filling can be performed without interfering with traffic below the precast concrete girder.

In addition, the joints constructed using this method are aesthetically pleasing as decorative joints because the blocks of the joint covering material form the outer surface of the joints.Furthermore, the blocks are at a certain height above the floor slab, so they do not require floor concrete. It can also be conveniently used as a ruler to determine the height of the top surface of the concrete floor during construction.

〔Example〕

As shown in FIG. 6, a 120 m long rock shade using precast concrete girders was constructed on a road with a width of 6 m, and its joints were constructed by the method of the present invention.

Figure 6(a) is a front view of the lock shade, Figure 6(b)
is a side view thereof, and its lateral extension is omitted. A partially cutaway perspective view of the lock shade shown in FIG. 6 is shown in FIG. Further, an enlarged view of part A in FIG. 6(b) is shown in FIG. 7.

In FIG. 6, the road 20 is adjacent to the slope 11,
A girder 14 was constructed on the concrete retaining wall 12 and pillars 13 to maintain a vehicle limit 16 and connected in the longitudinal direction of the road, and earth and sand 15 was placed thereon as a cushioning material. This rock shade not only maintains the necessary road space, but also protects the road 20 from falling rocks from above the slope 11, thereby ensuring the safety of road users.

As shown in FIG. 7, a joint was formed by covering the floor slab 17 of the girder 14 in contact with ps with a joint covering tool l. In addition, cross beams 15 are provided near both ends in the longitudinal direction of the beam 14 and at the center thereof, and the joints are formed using another joint cover 5.

The girder material used had the cross section shown in Figure 7, and its dimensions and specifications are as follows.

Construction road width: 6m Construction road vehicle limit double width 6000mm Height 4700mm Precast girder: Model: Box type precast girder, reinforced cross girder 3
Cutting section: width 1980mm x girder height 1000mm length: 9m slab thickness: 140mm joint opening dimensions: 20-40mm The joints of this precast girder will be constructed. 2nd
As shown in the figure, width 100mm, thickness 40mm, length 1
A first joint covering material 1 was prepared in advance by connecting two long and thin blocks 2 of m length with ten reinforcing bars 4 of 4 mm diameter. Also, for constructing the joints of the reinforcing cross beams 14 provided on the precast girders.

The second joint covering material 5 shown in FIG. 4 was also manufactured in advance. Second
The joint covering material 5 covers the exposed joint parts on three sides of the reinforcing cross beam 14, so the cross section is @100 m as shown in FIG.
Two opposing vertical covering blocks 6 with a thickness of 40 mm and a bottom block 7 with the same cross section were integrally molded to form a U-shape, and reinforcing bars 4 with a diameter of 6 mm were disposed inside the U-shape.

FIG. 5 is a perspective view illustrating the construction stage of this joint, with the front girder 14 partially cut out to show the state in which the joint covering materials 1 and 5 are attached to the joint.

Construction of the joints was carried out using the following steps (I), (II), and (m).

(I) Construction of the joints of the cross girder at the center of the precast girder (II) Construction of the joints of the deck slab (m) The above CI), (II), and (III) are applied to the construction method of the cross girder joints at the end of the precast girder. The construction procedures for each stage are as follows.

(I) Construction of joints of central cross beam 1) Erection of girder 14 on retaining wall 12 and pillar 13.

2) Attach the second joint covering material 5 shown in FIG. 4 to the joints of the central cross beams 18 of the adjacent girders 14. First, a sealing material or packing material is attached to the U-shaped bottom of the joint covering material 5, a rope is placed over the crossbeam, the barb joint covering material 5 is pulled up with this rope, and is attached to the crossbeam joint. Fig. 3 shows the state in which the joint covering material 5 is attached to the joint part of the cross beam 18, and Fig. 3 (a) is a horizontal cross-sectional view (
-■ Cross-sectional view in the direction of arrows), Figure 3 (b) is B- of Figure 3 Ca)
It is a view from arrow B.

3) A sealing material 8 is driven into the gap between the joint covering material 5 and the cross beam 18 through four holes 19 previously provided in the floor slab to prevent paste leakage when placing joint mortar.

4) Concrete or mortar is poured into the joint space formed by the joint covering material 5. The joint covering material 5 and the cross beam 18 are integrated via the mortar 9, the anti-slip key 18a, and the reinforcing bar 4.

5) Next, move on to construction of the floor slab joints.

(■) Construction of joints in the floor slab l) As shown in Figure 2, a joint covering material 1 is made in advance by connecting two flat concrete blocks 2.3 with a length of 1 m with reinforcing bars 4. , a sealing material is pasted on the upper surface of the block 3 below it.

2) The joint covering material 1 is sequentially inserted into the joints of the floor slabs 17 of adjacent girders 14 from both ends of the girders 14. The upper and lower blocks are inserted along the upper and lower surfaces of the floor slab, respectively, and the reinforcing bars 4 are inserted into the joints of the floor slab. FIG. 1 is a sectional view showing this state, and the joint covering material 1 is inserted into the joint formed by the floor slabs 17 of the adjacent girders 14. The joint covering material l is applied to the girder 1 from the central reinforced cross girder part of the girder 14 constructed in step A above.
Connects to the end of 4 without any gaps.

3) Use joint covering material 1 whose length is adjusted for the crossbeams 18 at both ends of the girder 14.

4) A sealing material such as wooden camber is placed between the block 2 above the joint covering material l and the upper surface of the floor slab 17 to keep the height of the block 2 constant.

5) Concrete or mortar 9 is poured into the joint space to create a tight joint, and the joint covering material 1 and the floor slab 17 are integrated via the mortar 9, the anti-slip key 17a, and the reinforcing bar 4. .

(III) Construction of cross girder joints at girder ends 1) Next, girder 1
The construction of the joints of the end cross beams 18 at both ends of 4 is the same as the construction of the center cross beams in step (II) above.

〔Effect of the invention〕

According to the method of the present invention, shoring and scaffolding are extremely simple, and since all parts are precast, there is less concrete cast in place, no formwork is required, there is no need to remove the frame, and there is no need for formwork installation or joint construction. Also, there is no need for scaffolding to repair the joints, and there is no danger of objects falling from the joints.
Shoring and scaffolding can be quickly removed. Therefore,
The construction period is shortened, and traffic closures and traffic restrictions can be significantly reduced.

In addition, the constructed joints have good waterproof performance and are decorative joints that are aesthetically pleasing. Furthermore, even if a part of the beam is damaged, that beam can be replaced.

In addition, in the above description, the rock shade was explained as an example, but the method of the present invention is not limited to this, and can be widely used for construction of joints of precast girders.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a floor slab joint showing an embodiment of the method of the present invention, Fig. 2 is a perspective view of a joint covering material, Fig. 3 is a sectional view of a joint of a crossbeam, and Fig. 4 is a U A perspective view of the letter-shaped joint covering material, Fig. 5 is a partially cross-sectional perspective view of the lock shade, Fig. 6 (a)
6 is a front view of the lock shade, FIG. 6(b) is a side view thereof, and FIG. 7 is an enlarged view of section A in FIG. 6(b). 1.5... Joint covering material, 2, 3... Block, 4.
・・Reinforcing bar, 9・mortar, 14・digit, 17・・
・Floor slab, 18... crossbeam.

Claims (1)

[Claims] 1. A joint covering material is made in advance by connecting two elongated blocks in parallel with reinforcing bars to cover both surfaces of the joint between the floor slabs, and the joint covering material is inserted into the joint from the end surface of the floor slab. The reinforcing bars are located within the joint and the two blocks are arranged so as to cover the surface of the joint of the floor slab, and the gap between the two blocks of the joint covering material and the floor slab and the inside of the joint are A method for constructing floor slab joints in precast concrete girders, characterized by placing mortar on the floor slab and integrating the joint covering material with the floor slab.