JP3066432B2 - Grout-proof curing material for floor slab support - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grout-preventing curing material used for filling grout between a floor slab and a girder supporting the slab in a viaduct on a highway or the like.

[0002]

2. Description of the Related Art In recent years, in the case of viaducts on expressways, so-called precast type slabs made of reinforced concrete already molded at a factory are placed on girders (1) and (1) in order to improve construction efficiency. (2) The construction method in which (2) is placed side by side in the longitudinal direction of the girders (1) and (1) is adopted. In this one,
As shown in FIG. 1, a grout (G) is formed between the floor slab (2) and the spar (1) in a bar shape. A pair of bar-shaped packing materials (3) and (3) are arranged side by side in such a manner that the floor slab (2) suspended by a crane etc.
Is placed on the packing materials (3) and (3) in this suspended state, and the suspended position of the floor slab (2) is finely adjusted,
It is positioned at a predetermined position. Thereafter, when the hanging force of the floor slab (2) is released, the spacers (not shown) provided between the floor slab (2) and the spar (1) allow the slab (2) and the spar (1) to be released. ) Is formed. Then, as shown in FIG. 2, a grout (G) such as a non-shrink mortar is filled between the packing materials (3) and (3) in the gap. At the time of this filling, the packing materials (3) and (3) function as leakage prevention for the grout (G). After curing of the grout (G), the floor slab (2) is firmly supported by the spar (1).

However, in this prior art, a floor slab is used.
When adjusting the suspension position in (2), the surface of the packing material (3) (3) having a large friction coefficient is slid and moved, so that the workability of this positioning is poor. Further, during the movement, the packing materials (3) and (3) are strongly rubbed against the floor slab (2), and the packing materials (3) and (3) are easily damaged. If these packing materials (3) and (3) are damaged, the grout (G) will leak during the above filling operation, and this grout (G) will
After adhering to (1) or after grout hardening,
A gap is formed between the slab and (1), and the supporting strength of the floor slab (2) is reduced.

[0004] The present invention has been made in view of the above points, and is described as "a grout for supporting a slab used when a grout is filled in a bar shape between a spar (1) and a slab (2). During the construction, the floor slab (2) is easily moved while the floor slab (2) is placed on the packing materials (3) and (3), and the packing is The object is to prevent the materials (3) and (3) from being damaged.

[0005]

[Technical Means] The technical means of the present invention taken to solve the above-mentioned problem is that "a pair of rubber packing materials (3) (3) (3) arranged side by side in a mode extending in the longitudinal direction of the spar (1). Each packing material (3) is formed in a rod shape, and a sliding tape (4) having a surface with a small friction coefficient is adhered to the entire upper surface thereof ”.

[0006]

The above technical means of the present invention operates as follows. In this case, since the sliding tape (4) is attached to the upper surface of each packing material (3) along the longitudinal direction of the packing material (3), the floor slab (2) is attached to the packing material (3) (3). In the mounted state, the floor slab (2) comes into contact with the sliding tapes (4) and (4). And
Since the sliding tapes (4) and (4) have a surface having a small coefficient of friction, the floor slab (2) and the packing material are used when the floor slab (2) is moved in the above-described state. (3) The frictional resistance acting between (3) and (3) is small.

[0007]

According to the present invention having the above configuration, the following specific effects are obtained. When the floor slab (2) is moved while the floor slab (2) is placed on the packing materials (3) (3), the frictional resistance acting on the floor slab (2) becomes small. Therefore, it is easy to move the floor slab (2). Further, since the frictional resistance acting on the packing members (3) and (3) during the movement is small, the packing members (3) and (3) are not easily deformed, and the damage is prevented.

Furthermore, since it is only necessary to attach a sliding tape (4) made of a resin tape, a kraft tape, or the like to the upper surface of each packing material (3), this attaching work is easy, and at the construction site, Is easier to handle.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, as shown in FIGS. 3 and 4, the above-mentioned girder (1) is made of a steel box girder, and the above-mentioned floor slab (2) supported by this girder is made of reinforced concrete. It is a precast floor slab, a pair of said girders (1) (1) side by side, on these girders (1) (1), a plurality of the said floor slabs are supported in a cross-linked manner by these (2) is densely arranged in the longitudinal direction of the girders (1) and (1).

The digit (1) is, as shown in FIGS.
It has a substantially rectangular cross section, and has a configuration in which haunch portions (21) (21) of a floor slab (2) described later are mounted on left and right ends of an upper flange (11). A pair of rod-shaped packing members (3) and (3) each having a rectangular cross section that runs along the longitudinal direction of the spar (1) are arranged in parallel on each mounting portion, and these packing members (3) and (3) A grout (G) described later is interposed between each other. Further, between the packing members (3) and (3), a plurality of positioning pins (5) and (5) attached to the upper flange (11) are arranged at predetermined intervals in the longitudinal direction of the spar (1). Are arranged one by one.

The floor slab (2) is formed in a rectangular plate shape, and is arranged in such a posture that its width direction coincides with the longitudinal direction of the spar (1). On the lower surface of the floor slab (2), a plurality of the haunch portions (2) extending in the width direction are provided.
1) (21) are juxtaposed. And this floor slab (2)
At positions corresponding to the haunch portions (21), through holes (23) and (23) having a rectangular cross section penetrating vertically are provided, and in each through hole (23),
The pair of positioning pins (5) (5) described above are fitted.
The width in the longitudinal direction of the floor slab (2) in the cross section of the through hole (23) substantially matches the left-right distance between the pair of positioning pins (5) (5). The long side of the floor slab (2) has a joint piece projecting from its lower end as shown in FIGS.
(22) and (22) are formed along the longitudinal direction of the floor slab (2), and the long side portion has a folded portion (R) (R) (R) at the end of the reinforcing bar constituting the floor slab (2). R) is protruding.

The packing material (3) is a natural rubber foam molded article having a hardness of about 25, and is bonded to the upper surface of the upper flange (11). Also, this packing material
A sliding tape (4) having a surface with a small coefficient of friction is adhered to the upper surface of (3) along the longitudinal direction thereof. In this embodiment, as the sliding tape (4),
A kraft tape (4a) is used, and the width of the kraft tape (4a) is made substantially equal to the width (W) of the cross section of the packing material (3).

Further, the cross-sectional dimensions of the packing material (3) are as follows:
It is selected from the usable range obtained by the following experiment. In this experiment, as shown in FIG. 10, a pair of test pieces (T) and (T) each having a rod shape with a rectangular cross section were fixed in parallel to a fixed wall (K), and these test pieces (T) and (T) were fixed. On the surface opposite to the fixing surface, the kraft tape (4a)
(4a) is adhered, and these test pieces (T) and (T) are sandwiched between a concrete block plate (M) and compressed to a predetermined degree (the state of FIG. 10A). Block board
(M) is first moved a set distance (L ₁ ) in the longitudinal direction of the test pieces (T) and (T) (the state shown in FIG. 1B), and thereafter, the test pieces (T) and (T) are moved. It is moved by a set distance (L ₂ ) in the width direction (the state shown in FIG. 1C).

An index line (S) is drawn in the center of the side surface of the test piece (T) (T) in the height direction, and the movement amount (L ₀ ) from the movement start point increases by 20 mm. Each time, the displacement (E) in the longitudinal direction of the test piece (T) at the upper end of the index line (S) is measured. Also, it is checked whether the test pieces (T) and (T) are not cracked or deformed in a cross-shaped shape during the compression and movement. Possible ”, and when the above-mentioned deformation or the like does not occur, it is determined that“ usable ”.

The test piece (T) has a length (L)
Is 600 mm and the width (W) of the cross section is 50 mm. The height (H) of the cross section is 50 mm (ratio of height (H) to width (W) (A) = 1.0), 60 mm (The ratio (A)
= 1.2), 80 mm (the ratio (A) = 1.6), 100
mm (the ratio (A) = 2.0). Also, the compressibility (C) of the cross section by the block plate (M)
(The compression amount (H) depends on the height (H) of the test piece (T) before compression.
_The above experiment was carried out by setting several values obtained by dividing ₁ ) and multiplying by 100). Further, the above set distance (L ₁ )
(L ₂ ) is the maximum value obtained by measuring the travel distance under actual construction conditions, and in this experiment, the set distance (L ₁ ) = 100 mm, the set distance (L ₂ ) = 20 mm.

The results of the experiment are as shown in Table 1 below.

[0017]

[Table 1]

According to Table 1, the ratio (A) is 2.0 to 2.0.
In the range of 1.0, the compression ratio (C) is 0 to
If the ratio (A) is in the range of 1.6 to 1.0 and the compression ratio (C) is 0 to 30%,
It can be seen that when (A) is in the range of 1.2 to 1.0, the compression ratio (C) can be set from 0 to 40%.
The compression ratio (C) is the packing material at the actual construction site (3)
Corresponds to the compression ratio in the height direction. Also, from this experimental result, the compression ratio (C) can be increased as the upper limit of the range is smaller, and the mutual pressing force between the floor slab (2) and the packing material (3) is increased. We can see that we can do it. Therefore, when the upper limit value is small, a large grout pressure can be countered during grout filling, which will be described later, and the effect of leaking grout is further ensured. In addition, the above height (H)
Is 50 mm (the above ratio (A) = 1.0),
Although not shown, the deformation and the like did not occur even when the compression ratio (C) was set to 0 to 40%.
Also, of course, for the ratio (A) = 1.0 or less,
It is presumed that the deformation or the like does not occur. Further, the values of the displacement (E) described in Table 1 are all smaller than those obtained when the same procedure was performed without attaching the kraft tape (4a) (not shown). Was. [Practice of Construction] Next, the work of installing the floor slabs (2) and (2) on the above-mentioned girders (1) and (1) will be described.

First, on the upper surface of the upper flange (11) of each girder (1), the girder is placed on the mounting portion of the haunch portions (21) (21) of the floor slab (2).
The pair of packing members (3) and (3) are adhered in a mode running along the longitudinal direction of (1). Then, the floor slab (2) suspended by a crane or the like is spanned over the girders (1) and (1),
The haunch part (21) is placed on the packing materials (3) (3). At this time, in the suspended state, the packing members (3) and (3) are compressed to a predetermined degree by the floor slab (2) (the state of FIGS. 5 and 6). In addition, when the pair of positioning pins (5) and (5) are inserted into the through holes (23) of the floor slab (2) at the time of mounting, the pair of positioning pins (5) and (5) are inserted. Since the left-right spacing of (5) substantially matches the longitudinal width of the floor slab (2) in the cross section of the through hole (23), the floor slab (2) is positioned in the longitudinal direction. State. In addition, in the width direction of the floor slab (2), there is room for the movement of the through holes (23) with respect to the positioning pins (5) and (5), so that the floor slab (2) and a set adjacent thereto are set. Usually, a gap is formed between the slab and the finished floor slab (2).

Thereafter, the floor slab (2) is moved in the width direction of the floor slab (2) in the suspended state, and a gap between the floor slab (2) and the set slab (2) is set. When squeezed, it is positioned at the final set position. At this time, the packing material (3)
Since the kraft tapes (4a) and (4a) are attached to the upper surface of (3), the floor slab (2) is a kraft tape (4a) (4a).
Comes into contact with the surface with a small coefficient of friction at
During the above movement, the frictional resistance acting on the floor slab (2) becomes small. Thus, the force required for moving the floor slab (2) is reduced, and the packing members (3) (3) are less likely to be deformed.

After this positioning, the wires and the like hanging the floor slab (2) are removed. At this time, support bolts (B) and (B) are screwed through the floor slab (2) so as to be located between the packing materials (3) and (3). Since the tip of (B) protrudes downward from the haunch part (21) by a predetermined height, the floor slab (2) is slightly lowered and the bolts (B) and (B) are brought into contact with the spar (1). Then, the floor slab (2) is supported by the beams (1) and (1) via the bolts (B) and (B). In this supporting state, a gap corresponding to the projecting height of the bolts (B) is formed between the haunch portion (21) and the spar (1). Note that the bolt (B) is set so that the compression ratio in the height direction of the packing material (3) in the gap forming state falls within the range of the usable compression ratio (C) obtained by the above experiment.
The protrusion height of (B) and the cross-sectional dimension of the packing material (3) are set.

When a non-shrink mortar as a grout (G) is injected into the gap from each through hole (23) of the floor slab (2), the gap is filled with the grout (G).
At this time, the packing members (3) and (3) prevent leakage of the grout (G). When the grout (G) hardens, the spar (1) and the haunch portion (21) are integrally connected, and the floor slab (2) is firmly supported by the spar (1). The grout (G) is filled and hardened in each through hole (23).

As shown in FIG. 9, a groove is formed between the floor slabs (2) and (2) by the joining pieces (22) and (22), and the floor slab (2) is formed in the groove. In the state (2), the folded portions (R) and (R) are alternately inserted. When the mortar is injected into the groove and cured, the floor slabs (2) and (2) are integrally connected. As shown in the figure, a packing material (P) is interposed between the joint pieces (22), (22), thereby preventing the mortar from leaking. [Regarding Modification] In the above embodiment, the girders (1) are steel box girders, but the present invention is not limited to this. For example, an I-girder or a reinforced concrete girder may be used.

[0024] In the above embodiment, the floor slab (2) is the above-mentioned precast slab. Alternatively, for example, a steel slab may be used. . In the above embodiment, the packing materials (3) and (3) are made of natural rubber. However, this may be a rubber molded product made of synthetic resin.

[Brief description of the drawings]

FIG. 1 is a perspective view of a floor slab support structure in a conventional example.

FIG. 2 is an explanatory view of a main part of this.

FIG. 3 is a sectional view of an embodiment of the present invention.

FIG. 4 is a plan view thereof.

FIG. 5 is a cross-sectional view of a main part thereof.

FIG. 6 is a side view of a main part of the embodiment.

FIG. 7 is a plan view showing the relationship between the through holes (23) and the positioning pins (5) (5).

FIG. 8 is a cross-sectional view of a main part after grout (G) injection.

FIG. 9 is a side view showing a joint between the floor slabs (2) and (2).

FIG. 10 is a schematic explanatory view of an experiment for setting a cross-sectional dimension of the packing material (3).

[Explanation of symbols]

 (1) ... girder (2) ... floor slab (3) ... packing material (4) ... sliding tape

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Komori 1-3-3 Nakase, Mihama-ku, Chiba-shi, Chiba Inside Sakurada Co., Ltd. Miyaji Iron Works Co., Ltd. (58) Fields investigated (Int. Cl. ⁷ , DB name) E01D 21/00 E01D 19/12

Claims (4)

(57) [Claims] A grout-preventing curing material for supporting a slab, which is used when a grout is filled into a bar between a spar (1) and a slab (2), in a manner extending in the longitudinal direction of the slab (1). It consists of a pair of rubber packing materials (3) and (3) arranged side by side.Each packing material (3) has a rod shape, and a sliding tape (4) having a surface with a small coefficient of friction is applied over the entire upper surface. Grout-proof curing material for floor slab support. 2. The packing material (3) has a rectangular cross section, and the height ratio (A) to the width of the cross section of the packing material (3) is 2.0 to 2.0.
The grout-proofing curing material for supporting a slab according to claim 1, wherein the curing material is 1.0. 3. The packing material (3) has a rectangular cross-sectional shape, and a ratio (A) of a height to a lateral width of the cross-section of the packing material is 1.6 to 3.
The grout-proofing curing material for supporting a slab according to claim 1, wherein the curing material is 1.0. 4. The grout for supporting a slab according to claim 1, wherein the cross-sectional shape of the packing material (3) is rectangular, and the ratio (A) of the height to the width of the cross-section is 1.2 or less. Restorative curing material.