JPH04237714A - Concrete reinforcing steel member - Google Patents

Abstract

PURPOSE:To suppress the cost and enhance the quality by coupling together a plurality of box-shaped sheet piles of steel equipped at the web with a number of holes through the fit joint at each side edge firmly, and forming each reinforcing member for large depth use wherein the bottom setting part is accomplished jointlessly. CONSTITUTION:A bi-arm joint 3 is welded to the side edge of a box-shaped steel or I-steel 2 having perforated web, and thereby a unitary box-shaped sheet pile 4 of steel is formed. A plurality of such sheet piles 4 are fitted together and coupled by the joints 3 and fixed through welding 8 to form a reinforcing member 1 for concrete. The bottom setting part 5 of this reinforcing member 1 is embodied jointlessly with out such joints 3, and a gap retaining plate 7 is fixed, according to necessity, horizontally at the undermost part 6. The reinforcing member 1 is placed in a large depth excavated hole using an extra-large crane or the like, and muddy water is solidified to construct a continuous underground wall, etc. Thereby the strength can be increased to contribute to prevention of deformation, etc., and easy and efficient execution of works be ensured, and concrete be placed smoothly to fill the spaces.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to reinforcing steel for concrete used in the civil engineering and construction fields, and is particularly suitable for constructing concrete structures constructed by the muddy water solidification method, and in particular for concrete suitable for continuous underground walls. Related to reinforcing bars.

0002

[Prior Art] As is well known, the reinforcing bars used in concrete structures are usually made of concrete steel bars assembled into a net or cage shape.
Especially when constructing large concrete structures such as continuous underground walls in the recent civil engineering and architectural fields,
As described in Japanese Unexamined Patent Publication No. 64-90314, cage-shaped reinforcing bars assembled into a desired shape are erected in muddy water (stabilizing liquid) in an excavation trench previously excavated in a predetermined ground to solidify the muddy water. Another method used is to insert mortar or concrete using tremie pipes.

By the way, manufacturing large-sized cage-shaped reinforcing bars requires a vast workshop and a large number of skilled technicians, and furthermore, in order to avoid deformation and distortion during erection, large-sized cage reinforcing bars are manufactured. Since the work had to be carried out carefully using heavy machinery, there were problems in that the work period was long and construction costs were high. Therefore, the present inventor manufactured a reinforcing bar material by fitting a plurality of steel sheet piles into a unit block,
An improved means of erecting the unit block reinforcing bars in muddy boreholes has been developed.

0004

[Problem to be Solved by the Invention] Large concrete structures, such as the continuous underground walls mentioned above, have recently become larger and larger, and are required to have a built-in depth of 50 m to nearly 100 m. As a result, there has been an extremely high demand for reinforcing bars that are structurally strong, easy to install, highly watertight, and inexpensive. However, cage reinforcing bars using steel bars as mentioned above have a depth of 50 mm.
If the thickness exceeds m, it becomes difficult to ensure mechanical strength, and manufacturing and erection costs become extremely high.Also, when constructing reinforcing bars by simply connecting and fixing steel sheet piles with joints, However, the problem is that the deeper the depth, the more difficult it becomes to connect, fit joints, and maintain the posture, which increases construction work costs.

[0005] The object of the present invention is to provide a reinforcing bar material that has high mechanical strength, does not require skilled skills to manufacture, has low joint processing costs, is easy to install, and can be filled with mortar or concrete smoothly. It is about providing.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the reinforcing bar material for concrete of the present invention is a reinforcing bar material made by fitting together and fixing a plurality of box-shaped steel sheet piles, and which has a lower end rooting portion. is formed without joints. The box-shaped steel sheet pile can be made of perforated web. Moreover, box-shaped steel sheet piles can be connected vertically and used.

[0007]

[Operation] The reinforcing bar material for concrete of the present invention is a reinforcing bar material that requires multiple box-shaped steel sheet piles to be connected and fixed by fitting together with joints, and has high mechanical strength, and can be assembled by fitting together joints and fixing by welding or joints. Since the plate connection is sufficient, no skilled work is required, and since the lower end penetration part is formed without a joint, the joint processing cost is low, making it highly economical. In addition, when perforated web box-type steel sheet piles are used as the material for concrete reinforcing bars and multiple perforated web box-type steel sheet piles are connected and fixed with joints, they have high mechanical strength and are easy to assemble, as described above. In addition, since the web has holes, filling with concrete is extremely smooth, and if the lower end penetration part is formed without a joint, the joint processing cost is low, which is advantageous in economic efficiency.

[0008] Next, there is a composite connected reinforcing bar made by vertically connecting a plurality of unit reinforcing bars formed by connecting and fixing a plurality of unit box-shaped steel sheet piles with joints, and in which the lower end rooting part is without a joint. In the case of concrete reinforcing bars that have been formed, they have extremely high mechanical strength, are strong enough to be used as reinforcing bars that need to be built over 50 meters long, and have a large tolerance for dimensional requirements, and can be used for any gigantic reinforcing bars. It is possible to meet various demands without compromising performance, and as with the above-mentioned reinforcing bars, assembly can be accomplished by fitting joints and fixing by welding or connecting joint plates, so no skilled work is required. Furthermore, since the lower end penetration part is formed without a joint, the joint processing cost is low, making it highly economical.

[0009] Furthermore, there is a composite connected reinforcing bar formed by vertically connecting a plurality of unit reinforcing bars formed by connecting and fixing a plurality of unit perforated web box-type steel sheet piles with joints, and which has no lower end rooting part. When using concrete reinforcing bars formed in joints, they similarly have extremely high mechanical strength and are strong enough to be used as reinforcing bars that need to be built at great depths. In response to requests for reinforcing bars,
It is possible to respond economically without reducing performance,
Furthermore, as with the above-mentioned reinforcing bars, assembly can be done by fitting joints and fixing by welding or connecting joint plates, so no skilled work is required.Furthermore, since the web is perforated, filling with mortar or concrete is extremely smooth, and steel Not only does it weigh less, but since the lower end penetration part is formed without a joint, the joint processing cost is low, making it extremely economical.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to embodiments. FIG. 1 is a schematic perspective view of a reinforcing bar material 1 for concrete according to the present invention. Although an example is shown in which individual joints are fitted, connected, and fixed to form a unit reinforcing bar, the lower end insertion portion 5 of the concrete reinforcing bar 1 is formed without a joint, as will be described in detail later. In other words, the perforated web I of the lower end insertion part 5
A double-arm joint 3 is not welded to the section steel 2, and a spacing band plate 7 is horizontally fixed to the lowermost end 6 of the perforated web I section 2, which is fixed as required. In addition, in this embodiment, the unit box-shaped steel sheet piles 4 are connected and fixed to each other by fitting the unit box-shaped steel sheet piles 4 together and then welding the joint part, and reference numeral 8 indicates the welded part. Furthermore, in addition to the above-mentioned welding, the connection can be fixed by means of fitting a cotter into the joint, means of abutting a perforated joint plate against a hole drilled in the flange and fastening it using a one-way tightening bolt, and horizontal welding of the connection beam material. It is also possible to employ fastening means such as the following, and in the present invention, the term "fitting, connecting and fixing joints of unit box-shaped steel sheet piles" is used in the above-mentioned meaning.

Next, FIG. 2 is a schematic perspective view of a reinforcing bar material 9 for concrete according to another embodiment of the present invention.
An example is shown in which six unit box-shaped steel sheet piles 12 made by welding 1 are connected and fixed through joints and configured as unit reinforcing bars. The reinforcing bar material 9 for concrete is also the reinforcing bar material 1 for concrete.
Similarly, the lower end penetration part 13 is formed without a joint, and furthermore, the lower end part 13 of the perforated web rectangular steel pipe 10 is equipped with a horizontal steel bar 14 having a spacing function and a truss having a function of increasing structural strength. A steel bar 15 is fixed by welding. The reinforcing bars 1 and 9 for concrete according to the present invention are structurally strong as described above and are formed into unit blocks, so as shown in FIG. Since the construction can be carried out at once in the excavated hole 16 without worrying about morphological deformation or distortion, the work can be carried out safely and extremely efficiently. In addition, when using I- or H-shaped steel or square steel pipes, which are the main structural members, with perforated webs as in this example, muddy water agitation efficiency is better than those with non-perforated webs. Good circulation of concrete and mortar, excellent placement efficiency, and good packing density.

Next, a box-shaped steel sheet pile, which is a main member used in the present invention, will be explained in detail according to an embodiment. FIG. 4 is a plan view of a box-shaped steel sheet pile 20 formed by welding joints 19a to 19d made of half-cut straight steel sheet piles to the flanges 18a to 18d of the I-beam 17, and FIG. 22a,
22b is a joint 23a to 2 made of a half-cut straight steel sheet pile.
It is a top view of box-shaped steel sheet pile 24 formed by welding 3d. Moreover, FIG. 6 is a schematic plan view of a reinforcing bar material 25 for concrete constructed by using five box-shaped steel sheet piles 20 and connecting and fixing them with joints. 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 also possible to use the well-known box-shaped steel sheet pile made by welding a male steel bar joint and a female steel pipe joint to the flange of a square steel pipe. However, since the box-shaped steel sheet piles 20 and 24 are all-strong joints, they have high structural strength and excellent water-stopping properties, so high economic effects can be expected. Furthermore, FIG. 7 shows a box-shaped steel sheet pile 27 having steel pipe female joints 26a to 26d in all of its joints, and is used for mutually connecting reinforcing bars for concrete. That is, as shown in FIG.
5a, and then use the box-shaped steel sheet piles 27 when erecting the subsequent concrete reinforcing bars 25b. Since the fit tolerance of the joint is large, it becomes easy to absorb dimensional errors in the erecting. Construction efficiency will be greatly improved.

[0013] Next, the reason why the lower end penetration part of the reinforcing bar for concrete according to the present invention is made without a joint will be explained in detail. FIG. 9 is a schematic cross-sectional view showing the state of ground excavation for constructing a continuous underground wall in building construction, and in FIG. 9, 28 to 35 indicate strata having different properties. As is well known, in order to construct a continuous underground wall, drilling holes 36a and 36b are dug using muddy water drilling means, concrete reinforcing bars 25c and 25d are built into the drilling holes 36a and 36b, and the muddy water is solidified. Soil excavation was carried out to enclose wall space 37.
Then, the bottom slab concrete 38 is poured and the side walls are constructed, but the explanation of the side wall construction will be omitted. Now, the drilling of the boreholes 36a and 36b is carried out in the easily permeable stratum 29,
31 until the tip 39 reaches the supporting stratum 35 which is hardly permeable or impervious to water. In this case, since the conventional technology has little experience in constructing continuous underground walls at great depths, the joints are attached to the total length H of the concrete reinforcing bars 25c and 25d, that is, (h1 + h2 = H) in Fig. 9. has been adopted as an essential requirement. However, the research conducted by the present inventors has confirmed that joints are not necessary for the lower end of the reinforcing bar for deep continuous underground walls, and that the lower end of the reinforcing bar only needs to bear the vertical load. The bottom root root is solidified with muddy water.
Alternatively, it has been found that it has sufficient load bearing capacity when placed in mortar or concrete. In other words, in Fig. 9, the water-stopping properties of concrete reinforcing bars 25c and 25d are 40
Depth h from to the bottom 41 of the bottom slab concrete 38
1. The drilling hole 36a is required from the bottom 41.
, 36b to the tip 39 was found to be unnecessary. In other words, as was previously feared, excavation will lower the groundwater level and cause the formation of easily permeable strata29.
, 31 is not easily permeable, but it is not easily permeable, but there is no risk that the groundwater will gather at the lower part of the bottom concrete 38 from the permeable strata 32, 33, and 34 and cause spring water that is inconvenient for the construction, and the muddy water at the lower end rooting part will solidify. It has been found that the lower part of a continuous underground wall constructed by pouring concrete or pouring concrete can sufficiently prevent such seepage of groundwater. In the present invention, the portion equivalent to the depth h2 of the concrete reinforcing bars 25c and 25d is defined as the lower end penetration portion. As for the lower end penetration, as mentioned above, the absolute length differs depending on the construction conditions, that is, the planned construction depth, ground type, and water stoppage conditions, and cannot be determined unambiguously.
Although a design is required for each case, in research conducted by the present inventors, the lower end penetration depth h2 is often about 10 to 35% of the total length H.

[0014] The present inventor has reduced the cost of reinforcing bars for concrete by 3 to 8% by eliminating the joint at the lower end penetration part to reduce the weight of the material and the cost of processing the joints. succeeded in doing so. Now, as mentioned above, when constructing a continuous underground wall with a depth of 50 to 100 meters, concrete reinforcing bars must be long enough to handle the length, but current production technology means that There are limits to the length of I-beams, H-beams, and square steel pipes as members. Therefore, long concrete reinforcing bars 42 and 43 are suitable for continuous underground walls at great depths.
10 and 11, unit reinforcing bars 44a, 44b and 45a, 45b, which are made by fitting together and fixing a plurality of unit perforated web box-shaped steel sheet piles, are vertically connected. However, in manufacturing, unit reinforcing bars 46 and 47 whose lower ends have no joints are used in advance, and as a whole long concrete reinforcing bars 42 and 4 whose lower ends have no joints are constructed.
Needless to say, 3 is formed. The reinforcing bars 42 and 43 for long concrete are composed of unit perforated web box-shaped steel sheet piles connected in two directions, horizontal and vertical. Therefore, in the present invention, the reinforcing bars 42 and 43 for long concrete are , 43 are hereinafter referred to as composite connected reinforcing bars. Also,
Although the explanation was omitted in the example, instead of the unit perforated web box-shaped steel sheet piles, a plurality of unit reinforcing bars made by connecting and fixing a plurality of non-perforated web box-shaped steel sheet piles with joints were further added vertically. In the example of connecting composite connected reinforcing bars, that is, producing long concrete reinforcing bars, it is advantageous in terms of price because there is no web processing cost, but it requires repeated pouring work using tremie pipes when concrete is poured. As mentioned above, the concrete placement efficiency is slightly lower than that of perforated webs.

[0015] Next, as mentioned above, it is economically effective to manufacture and use the reinforcing bars for concrete as long as possible in one piece, but there are constraints on site work. In other words, if there are restrictions on weight or dimensions, it will be necessary to connect unit reinforcing bars one after another at the work site. FIG. 12 is a schematic diagram showing the situation in which the reinforcing bars for long concrete are erected while sequentially connecting the unit reinforcing bars.
When constructing the concrete, a device 50 is installed on the ground above the excavation hole 49 to grip and release the long concrete reinforcing bars 42, and temporarily grip and hold the long concrete reinforcing bars 42. Connecting unit reinforcing bars is carried out while accurately maintaining the erection position. In addition, when sequentially connecting the unit reinforcing bars for the structure of the long concrete reinforcing bars 42, as shown in the partial schematic cross-sectional views of FIGS. By employing a means of abutting the joint plates 52 and fastening them using one-way tightening bolts 53, the connection work can be carried out quickly. Figure 1
3. FIG. 14 is an example in which a honeycomb H-shaped steel 54 is used as a component, and as a means for providing a through hole 55 in the web,
This method is more economical than the method of drilling holes in a section steel web, and is suitable for the reinforcing steel for concrete of the present invention.

[0016]

[Effects of the Invention] The reinforcing steel for concrete of the present invention uses box-shaped steel sheet piles as the main component, and is constructed by connecting and fixing the box-shaped steel sheet piles with joints, so it has high mechanical strength and is easy to manufacture. There is no need for skilled skills, and since there is no joint at the lower end, the joint processing cost is low, making it extremely economical to manufacture. Furthermore, since it is a unit block structure, it is easy to build, and since there is no morphological deformation or distortion, there is no need for skilled technicians, and work efficiency is very high, resulting in a significant reduction in concrete structure construction costs. can be lowered. Furthermore, when unit reinforcing bars are connected vertically to form long box-shaped steel sheet piles, they have higher mechanical strength and are easier to erect than conventional reinforcing bar cages. In the case of reinforcing bars made using sheet piles, filling with mortar and concrete is smooth and a concrete structure with high reliability can be obtained, making it particularly suitable for constructing deep concrete structures. Its practical effects as a reinforcing bar material are extremely large.

[Brief explanation of the drawing]

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 the reinforcing steel for concrete according to the present invention.

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

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

FIG. 5 is another schematic plan view of a box-shaped steel sheet pile as a component.

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

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

FIG. 8 is a schematic explanatory diagram showing the installation status of concrete reinforcing bars.

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

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

FIG. 11 is another schematic explanatory diagram of the elongated reinforcing bar material for concrete according to the present invention.

FIG. 12 is an explanatory diagram of the installation situation of reinforcing steel for concrete.

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

FIG. 14 is another partial schematic explanatory diagram showing the connection state of unit reinforcing bars.

[Explanation of symbols]

1 Reinforcement material for concrete 2 Perforated web I-shaped steel 3 Double-arm joint 4 Unit box-shaped steel sheet pile 5 Lower end penetration part 6 Bottom end part 7 Spacing retaining strip 8 Welded part 9 Reinforcement material for concrete 10 Perforated web square steel pipe 11 Double-arm joint 12 Unit box-shaped steel sheet pile 13 Lower end 14 Horizontal steel bar 15 Truss steel bar 16 Drill hole 17 I-beam 18a-18d Flanges 19a-19d Joint 20 Box-shaped steel sheet pile 21 Square steel pipes 22a, 22b Flanges 23a-23d Joint 24 Box-shaped steel sheet piles 25, 25c, 25d Reinforcing bars for concrete 26a
~26d Female steel pipe joint 27 Box-shaped steel sheet piles 28-35 Geological strata 36a, 36b Excavation hole 37 Surrounding wall space 38 Bottom slab concrete 39 Tip 40 Ground surface 41 Bottom 42, 43 Concrete reinforcing bars 44a, 44b Unit reinforcing bars 45a, 45b Unit reinforcing bars 46, 47 Unit reinforcing bars 48 Super-large crane 49 Excavation hole 50 Gripping device 51 Butt welding 52 Perforated joint plate 53 One-way tightening bolt 54 Honeycomb H-shaped steel 55 Through hole

Claims (4)

[Claims] 1. A reinforcing bar material for concrete, which is made up of a plurality of box-shaped steel sheet piles connected and fixed by fitting together with a joint, and whose lower end penetration portion is formed without a joint. 2. A reinforcing bar material for concrete, which is made by connecting and fixing a plurality of perforated web box-type steel sheet piles with joints, and in which the lower end rooting part is formed without a joint. [Claim 3] A composite connected reinforcing bar material made by longitudinally connecting a plurality of unit reinforcing bars formed by connecting and fixing a plurality of unit box-shaped steel sheet piles with joints, and in which the lower end penetration part is formed without a joint. Reinforcement material for concrete. [Claim 4] A composite connected reinforcing bar material formed by vertically connecting a plurality of unit reinforcing bars formed by connecting and fixing a plurality of unit perforated web box-type steel sheet piles with joints, and having no lower end rooting part. Concrete reinforcing bars formed in joints.