JP2852566B2 - Reinforcing bars for concrete - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing steel material for concrete used in the fields of civil engineering and construction, and more particularly to a concrete structure suitable for construction of a concrete structure constructed by a method of solidifying muddy water, especially for a continuous underground wall. Pertains to reinforced material.

[0002]

2. Description of the Related Art As is well known, as a reinforcing material usually used for a concrete structure, a steel bar formed by assembling steel bars for concrete and forming a net shape or a basket shape is employed.
Especially when building large concrete structures such as recent civil engineering and continuous underground walls in the construction field,
As described in JP-A-64-90314, a basket-shaped reinforcing bar assembled in a desired form is built in muddy water (stable liquid) of a digging groove excavated in a predetermined ground in advance to solidify the muddy water. In addition, a means of inserting mortar or concrete with a tremy tube is employed.

[0003] By the way, in order to manufacture a large-sized cage-shaped rebar, a large work area and a large number of skilled technicians are required. Since careful work has to be performed using heavy equipment, there has been a problem that the work period is long and the construction cost is high. Therefore, the present inventor manufactured a rebar material as a unit block by joint fitting a plurality of steel sheet piles,
An improved means of embedding the unit block reinforced material in a mud drill hole has been developed.

[0004]

The large-sized concrete structures represented by the continuous underground walls described above are becoming increasingly large, and are required to have a building depth of 50 m to 100 m. Therefore, there has been a great demand for a steel reinforcing material which is structurally strong, easy to be built in, has good water stopping properties, and is inexpensive. However, the above-described basket-type bar using steel bars has a depth of 5 mm.
In the case of reaching 0 m or more, in particular, it is difficult to secure mechanical strength, and the manufacturing cost and the erection cost become extremely high. However, as the depth becomes deeper, the connection, the fitting of the joint and the holding of the posture become more difficult, and the construction work cost increases.

An object of the present invention is to provide a reinforcing steel material which has a high mechanical strength, does not require skilled skills in production, has a low joint processing cost, is easy to set up, and can be smoothly filled with mortar or concrete. To provide.

[0006]

According to the present invention, there is provided a reinforcing steel material for concrete, comprising a plurality of box-shaped steel sheet piles which are jointed and connected to each other. Are formed jointlessly. The box-shaped steel sheet pile may be a perforated web. Further, a box-type steel sheet pile can be used by being connected in the vertical direction.

[0007]

The reinforcing steel material for concrete according to the present invention is a reinforcing steel material which requires a plurality of box-shaped steel sheet piles to be fitted and connected and fixed. The mechanical strength is high, and the assembling is performed by joint fitting and welding fixing or seaming. Skilled work is not required because plate connection is sufficient, and since the lower end root portion is formed without a joint, the cost for joint processing is low and the cost is high. Also, when a perforated web box type steel sheet pile is used as a material of the reinforcing steel material for concrete and a plurality of perforated web box type steel sheet piles are jointed and connected and fixed as described above, the mechanical strength is large and the assembly is easy. In addition, since the web is perforated, the filling of the concrete is extremely smooth, and if the lower end root is formed without a joint, the cost of joint processing is low, which is advantageous in terms of economy.

Next, a composite rebar material is obtained by connecting a plurality of unit box-type steel sheet piles, which are jointly connected and fixed, and a plurality of unit rebar members are vertically connected, and the lower end of the steel sheet pile has no joint. In the case of the formed rebar for concrete, the mechanical strength is extremely high, it is sufficiently rigid as a rebar that needs to be built up to 50 m or more, and the tolerance for dimensional requirements is large. It is possible to meet the demand without deteriorating the performance. Further, as in the case of the above-mentioned rebar material, the fitting operation and the welding fixation or the connection of the seam plate are sufficient, so that no skill is required. Further, since the lower end root portion is formed without a joint, the joint processing cost is low and the cost is high.

[0009] Further, the present invention is a composite rebar material in which a plurality of unit rebar materials formed by fitting and connecting and fixing a plurality of unit-perforated web box-type steel sheet piles, and a plurality of the unit rebar materials are longitudinally connected, and a lower end rooted portion is not provided. When using the reinforcing steel material for concrete formed in the joint, similarly, the mechanical strength is extremely high, it is sufficiently strong as a reinforcing steel bar that needs to be built at a large depth, the tolerance for dimensional requirements is large, and a huge As for the demand for reinforcing steel,
It is possible to respond economically without deteriorating performance,
Furthermore, as in the case of the above-mentioned rebar material, similar to the above-mentioned rebar material, fitting work and welding fixation or seam plate connection are required, so skillful work is not required, and since the web is perforated, the filling of mortar and concrete is extremely smooth, In addition to reducing the weight, the lower end is formed without a joint, so that the joint processing cost is cheap and the economy is very high.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic perspective view of a concrete reinforcing bar 1 according to the present invention. The concrete reinforcing bar 1 has a unit box-type steel sheet pile 4 formed by welding a double-arm joint 3 to a perforated web I-beam 2. An example is shown in which individual joints are connected and fixed to form a unit rebar material. As will be described in detail later, the lower end root portion 5 of the concrete rebar material 1 is formed without a joint. In other words, in other words, the perforated web I
The double-armed joint 3 is not welded to the section steel 2, and a gap maintaining strip 7 is fixed horizontally to the lowermost end 6 of the perforated web I section 2 as required. In this embodiment, the unit box-type steel sheet piles 4 are connected and fixed to each other by means of fitting the unit box-type steel sheet piles 4 to each other and then welding the joints. Reference numeral 8 denotes a welded portion. In addition, in addition to the above-mentioned welding, means for fitting a cotter into a joint portion, means for contacting a perforated seam plate with a hole drilled in a flange and fastening with a one-way tightening bolt, and laterally welding a connecting beam material are used for connecting and fixing. It is also possible to adopt a fastening means such as the above, and in the present invention, the joint fitting connection fixing of the unit box type steel sheet pile is used in the above-mentioned meaning.

Next, FIG. 2 is a schematic perspective view of a reinforcing steel member 9 for concrete according to another embodiment of the present invention.
1 shows an example in which six unit box-type steel sheet piles 12 formed by welding 1 are fitted and connected and fixed to each other as a unit rebar material. The concrete reinforcing bar 9 is also used for the concrete reinforcing bar 1.
In the same manner as described above, the lower end insertion portion 13 is formed without any joint, and the lower end portion 13 of the perforated web square steel pipe 10 is further provided with a horizontal steel bar 14 having a spacing maintaining function and a truss having a function of increasing structural strength. The steel bar 15 is fixed by welding. Since the concrete reinforcing members 1 and 9 according to the present invention are structurally strong as described above and are formed in a unit block, as shown in FIG. Therefore, the work can be safely and extremely efficiently carried out in the excavation hole 16 without any fear of morphological deformation or distortion. In addition, in the case of using an I or H section steel or a square steel pipe as a main component having a perforated web as in this embodiment, the muddy water stirring efficiency is better than that of a non-perforated web, Good wraparound of concrete and mortar, excellent casting efficiency, and good packing density.

Next, a box-shaped steel sheet pile as a main member used in the present invention will be described in detail with reference to examples. FIG. 4 is a plan view of a box-shaped steel sheet pile 20 formed by welding joints 19a to 19d each formed by cutting a straight steel sheet pile to flanges 18a to 18d of an I-shaped steel 17, and FIG. 22a,
22b, a joint 23a-2 made of a half-section of a straight steel sheet pile
It is a top view of the box-shaped steel sheet pile 24 welded by 3d. FIG. 6 is a schematic plan view of a reinforcing steel member 25 for concrete which is formed by fitting and connecting and fixing five box-shaped steel sheet piles 20. In the present invention, in addition to using the box-shaped steel sheet pile 20 and the box-shaped steel sheet pile 24, it is possible to use a well-known box-shaped steel sheet pile made by welding a steel bar male joint and a steel pipe female joint to a flange of a square steel pipe. However, since the box-shaped steel sheet piles 20 and 24 are especially full-strength joints, they have high structural strength and excellent water stopping properties, so that high economic effects can be expected. Further, FIG. 7 shows a box-shaped steel sheet pile 27 having steel pipe female joints 26a to 26d in all of the joints, which are used for connecting rebars for concrete. That is, as shown in FIG.
When the box-shaped steel sheet pile 27 is used for mounting the concrete reinforcing bar 25a and then for the subsequent reinforcing steel material 25b, the fitting tolerance of the joint is large, so that the dimensional error of the built-in can be easily absorbed. Construction efficiency is greatly improved.

Next, the reason why the lower end root of the concrete reinforcing bar according to the present invention is made jointless will be described in detail. FIG. 9 is a schematic sectional view showing a ground excavation state for constructing a continuous ground wall in building construction. In FIG. 9, reference numerals 28 to 35 denote strata having different properties, respectively. As is well known, in order to construct a continuous underground wall, the excavation holes 36a and 36b are dug by the mud excavating means, and the reinforcing steel members 25c and 25d for concrete are built in the excavation holes 36a and 36b, and the mud is solidified. Excavation of soil and wall space 3
7 is constructed, and then the bottom slab concrete 38 is cast to perform the side wall construction, but the description of the side wall construction is omitted. Now,
The excavation of the excavation holes 36a and 36b is performed by the permeable stratum 2
9 and 31 until the tip 39 reaches the poorly permeable or impermeable support layer 35. In this case, according to the conventional technique, since the construction experience for the continuous underground wall at a large depth is small, the joint is attached to the entire length H, that is, (h ₁ + h ₂ = H) in FIG. 9 for the concrete reinforcing members 25c and 25d. Have been adopted as mandatory requirements. However, in the study of the inventors of the present invention, it was confirmed that the joint at the lower end penetration part was unnecessary particularly as a reinforcing steel material for a large-depth continuous underground wall, and the lower end penetration part was only required to bear mainly vertical load. Mud solidified at the lower end,
Or it turned out that it has sufficient load-bearing capacity by mortar or concrete casting. That is, in FIG. 9, the waterproofness of the concrete reinforcing members 25c and 25d is
H from the bottom to the bottom 41 of the bottom concrete 38
It is necessary up to ₁ equivalent, and the drill hole 36a from the bottom 41,
It was found that there is no need for deep h ₂ equivalent to 36b of the tip 39. In other words, the excavation lowers the groundwater level and raises the water permeability
There is no danger that the groundwater exuded from 1 is not easily permeable, but gathers from the permeable formations 32, 33, 34 at the bottom of the bottom concrete 38 and generates spring water that is inconvenient for construction.
It has been found that the lower part of the continuous underground wall constructed by solidification of muddy water or concrete casting at the bottom of the lower end can sufficiently prevent such seepage of groundwater. The present invention defines for concrete reinforcing bar 25c, the depth h ₂ equivalent of 25d and lower end roots join the club. As described above, the absolute length of the lower end penetration part is different depending on the construction conditions, that is, the planned construction depth, the ground type, and the water stoppage condition, and is not uniquely determined, and it is necessary to design each time. , lower roots join the club depth h ₂ is the study of the present inventors is often there with 10% to 35% approximately of the total length H.

The inventor of the present invention has reduced the cost of the concrete reinforcing bar by 3 to 8% by eliminating the joint at the lower end of the reinforcing bar for the concrete reinforcing bar and reducing the material weight and the joint processing cost. Was successful.
Now, when constructing a continuous underground wall of a large depth reaching 50 to 100 m as described above, it is required that the reinforcing steel material for concrete be long enough to cope with it. There are restrictions on the length of I-beams, H-beams, and square steel pipes as members. Accordingly, long concrete reinforcing bars 42 and 43 suitable for large-depth continuous underground wall reinforcing bars.
As shown in FIGS. 10 and 11, the unit rebar members 44a, 44b and 45a, 45b formed by fitting and connecting and fixing a plurality of unit perforated web box-shaped sheet piles are longitudinally connected as shown in FIGS. In the production, the unit rebar members 46 and 47 having no joints at the lower end are used in advance, and the lower end root portions are jointless and have no joints at all.
Needless to say, 3 is formed. The long concrete reinforcing bars 42, 43 are formed by combining unitary perforated web box-shaped sheet piles in a composite direction in the horizontal and vertical directions. Therefore, in the present invention, the long concrete reinforcing bars 42, 43 are provided. , 43 are hereinafter referred to as composite connecting reinforcing bars. Also,
Although the description is omitted in the embodiment, in place of the unit perforated web box-shaped steel sheet pile, a plurality of unit rebar members formed by fitting and connecting and fixing a plurality of non-perforated web box-shaped steel sheet piles are further vertically arranged. In the example where the composite connected reinforcing bar material, that is, the long concrete reinforcing bar material is manufactured by linking, it is advantageous in terms of cost because there is no web processing cost. As described above, the efficiency of concrete casting is slightly lower than that of a perforated web as described above.

Next, as described above, it is highly economical to manufacture and use a long piece of concrete reinforcing steel material according to the present invention, as described above, but the constraint on site work is high. In other words, when there are restrictions on the weight and dimensions, it is necessary to sequentially connect the unit reinforcing members at the work site. FIG. 12 is a schematic diagram showing a state in which a long concrete reinforcing bar is built while sequentially connecting unit reinforcing bars.
In order to erection, a device 50 is provided on the upper ground of the excavation hole 49 for grasping and releasably holding the long concrete reinforcing bar 42, and while temporarily holding the long concrete reinforcing bar 42, Perform the connection work of the unit rebar material while keeping the erection position accurately. Further, in order to connect the unit rebar materials sequentially because of the configuration of the rebar material 42 for long concrete, as shown in the partial schematic cross-sectional views of FIGS. If a means for abutting the seam plate 52 and fastening it with the one-way fastening bolt 53 is employed, the connection work can be performed quickly. FIGS. 13 and 14 show an example in which a honeycomb H-section steel 54 is used as a constituent member. As means for providing a through hole 55 in a web, FIG.
It is more economical than a means for perforating an H-section steel web and is suitable for the reinforcing steel material for concrete of the present invention.

[0016]

The reinforcing steel material for concrete of the present invention uses a box-shaped steel sheet pile as a main component and is formed by fitting and connecting and fixing the box-shaped steel sheet pile, so that the mechanical strength is high, and There is no need for skilled skills, and since there is no joint at the lower end, the joint processing cost is low and it can be manufactured extremely economically. In addition, since it is a unit block, it can be easily built in, and there is no need for skilled technicians because there is no morphological deformation or distortion, and the work efficiency is very good. Can be reduced. In addition, when unit steel bars are longitudinally connected to form a long box-shaped steel sheet pile, mechanical strength is higher than conventional steel cages, and it is easier to set up. In the case of steel bars made of sheet piles, mortar and concrete can be filled smoothly, and concrete structures with high quality can be obtained. The practical effect as a rebar material is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a reinforcing steel material for concrete according to the present invention.

FIG. 2 is another schematic perspective view of a reinforcing steel material for concrete according to the present invention.

FIG. 3 is a schematic plan view showing a state where concrete reinforcing bars are installed.

FIG. 4 is a schematic plan view of a box-shaped steel sheet pile as a constituent member.

FIG. 5 is another schematic plan view of the box-shaped steel sheet pile of the constituent members.

FIG. 6 is a schematic plan view of a reinforcing steel material for concrete.

FIG. 7 is a schematic plan view of a box-shaped steel sheet pile having steel pipe female joints in all the joints.

FIG. 8 is a schematic explanatory view showing a reinforced state of concrete reinforcing bars.

FIG. 9 is a schematic sectional view showing a ground excavation state for constructing a continuous underground wall in building construction.

FIG. 10 is a schematic explanatory view of a long reinforcing steel material for concrete according to the present invention.

FIG. 11 is another schematic explanatory view of a long concrete reinforcing bar according to the present invention.

FIG. 12 is an explanatory view showing a state of installation of a reinforcing steel material for concrete.

FIG. 13 is a partial schematic explanatory view showing a connection state of unit reinforcing bars.

FIG. 14 is another partial schematic explanatory view showing the connection state of the unit rebar members.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reinforcing material for concrete 2 Perforated web I-section steel 3 Double arm joint 4 Unit box-shaped steel sheet pile 5 Lower end penetration part 6 Lowermost end part 7 Retention strip 8 Welding part 9 Reinforcing material for concrete 10 Perforated web square steel pipe 11 Double arm joint 12 Unit box-shaped steel sheet pile 13 Lower end part 14 Horizontally installed steel bar 15 Truss steel bar 16 Drilling hole 17 I-shaped steel 18a-18d Flange 19a-19d Joint 20 Box steel sheet pile 21 Square steel pipe 22a, 22b Flange 23a-23d Joint 24 Box-shaped steel sheet pile 25, 25c, 25d Reinforcing bar material for concrete 26a-26d Steel pipe female joint 27 Box-shaped steel sheet pile 28-35 Formation 36a, 36b Excavation hole 37 Surrounding wall space 38 Bottom concrete 39 Tip 40 Ground surface 41 Bottom 42, 43 Reinforcing material for concrete 44a, 44b Reinforcing material 45a, 45b Reinforcing material 46, 47 Single Reinforcing bar 48 ultra large crane 49 borehole 50 gripping apparatus 51 butt welded 52 perforated seam plate 53 in one direction and tighten bolt 54 honeycomb H-beam 55 through hole

Claims (4)

(57) [Claims] 1. A reinforcing steel material comprising a plurality of box-shaped steel sheet piles fitted, connected and fixed to each other, and a lower end rooted portion formed without a joint. 2. A rebar material comprising a plurality of perforated web box-type steel sheet piles which are jointed, connected and fixed, and a lower end rooted portion of which is formed without a joint. 3. A composite connection rebar material in which a plurality of unit box-type steel sheet piles are jointly connected and fixedly connected to each other, and a plurality of unit rebar members are longitudinally connected, and a lower end rooted portion is formed without a joint. Rebar material for concrete. 4. A composite connection rebar material in which a plurality of unit rebar materials formed by connecting a plurality of unit-perforated web box-type steel sheet piles by joint fitting connection and fixed, and a plurality of the unit rebar materials are longitudinally connected, and having no lower end root portion. Rebar for concrete formed on joints.