JPH0442500B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a reinforcing bar cage assembly for an underground continuous wall and a joining method for connecting reinforcing bar cage blocks that are formed separately.

(Conventional technology) Constructing an underground continuous wall involves excavating a predetermined trench width and depth, filling the trench with stabilizing liquid to prevent the excavated trench wall from collapsing, and then building a pre-assembled reinforcing bar cage. This is done by forming the wall by pouring concrete into the concrete and replacing it with a stabilizing liquid. If the wall depth is to be increased, the reinforcing bar cage is divided into blocks, and the split reinforcing bar cage blocks are joined during construction on site to obtain a predetermined reinforcing bar cage length, and the wall body is then formed according to the above-mentioned procedure. These divided reinforcing bar cage blocks are connected using reinforcing bars in the depth direction of the wall, and a structure is required to hold the weight of the reinforcing bar cage below the joint.

Conventionally, split reinforcing bar cage blocks are joined by welding, where the reinforcing bars to be joined are overlapped at a predetermined length and the joint is strong enough to hold the weight of the reinforcing bar cage below. Construction Guidelines for Underground Continuous Wall Foundation Construction Method (Draft),” July 1985, Continuous Underground Wall Foundation Association, p. 81). This is shown in FIG. Reinforcing bars 11, which are the main components of the reinforcing bar cage, are connected at welded portions 12. The reinforcing frame 4 mainly plays the role of maintaining appropriate spacing between reinforcing bars. The reinforcing frame 4 and the reinforcing bars 11 are connected at a weld 14. In this way, the reinforcing bar cage having the reinforcing bars 11 as its main component is integrated.

(Problem to be solved by the invention) The conventional work of joining divided reinforcing bar cage blocks is as follows:
The lower reinforcing bar cage block to be joined is temporarily held at a certain height from the groove mouth, and in that state, the upper reinforcing bar cage block to be joined next is suspended by a crane and brought close to each other to ensure a predetermined overlap margin. Stop in place and complete the connection by arc or gas welding. However, it is generally known that the fatigue strength of reinforcing bars that are assembled by welding is lower than that of reinforcing bars that are not welded. Furthermore, during construction, it is necessary to manage various types of welding, such as selecting a welding rod that matches the material and strength of the reinforcing bars, drying the welding rod before use, preheating the reinforcing bars, and limiting welding speed. Measures must be taken to protect the work from wind and rain. Therefore, the conventional work of joining the divided reinforcing bar cage blocks not only reduces the strength of the reinforcing bars themselves, but also causes a large loss in terms of time and cost in the reinforcing bar cage erection work.

The present invention provides a reinforcing bar cage assembly and a joining method designed to facilitate the joining work of reinforcing bar cage blocks.

(Means for Solving the Problems) The present invention provides screw reinforcing bars arranged at regular intervals, a reinforcing frame for maintaining the spacing between the threaded reinforcing bars and preventing deformation, and threaded reinforcing bars arranged orthogonally to the threaded reinforcing bars. and a reinforcing bar support frame with through holes at the same spacing, and U-shaped bolts are used at the intersection of the threaded reinforcing bars and the reinforcing reinforcing frame, and the longitudinal direction of the reinforcing bars is free, while the other direction is free of the gap between the U-shaped bolts. An underground structure characterized by forming a free bundling structure within the ground, and forming a support structure in which the reinforcing bars are constrained in one longitudinal direction by passing screw reinforcing bars through holes in the reinforcing bar support frame and screwing fixing nuts. In a method of forming a continuous wall using a reinforcing bar cage assembly for a continuous wall and a reinforcing bar cage block formed mainly of threaded reinforcing bars arranged at regular intervals, the upper part of the lower reinforcing bar cage block that has been temporarily installed is Hang the upper reinforcing bar block that will be connected next to the block, match the upper threaded reinforcing bar end of the lower reinforcing bar cage block with the lower threaded reinforcing bar end of the upper reinforcing bar cage block individually, and fasten each with a coupler. This is a method of joining reinforcing bars for underground continuous walls, which is characterized by their integration.

(Operation, Example) Next, the operation of the present invention will be explained based on the illustrated embodiment.

FIGS. 1 and 2 are diagrams showing embodiments of the present invention. Threaded reinforcing bars 1, which form the main part of the reinforcing bar cage, mainly share the strength in the depth direction of the wall. Although the transverse reinforcement 1a is not particularly limited, the use of threaded reinforcing bars has the advantage that subsequent lateral connections are facilitated. The fixing nut 2 screwed into the threaded reinforcing bar 1 prevents the threaded reinforcing bar 1 from moving more than necessary during construction. The reinforcing bar support frame 3 and the reinforcing bar reinforcing frame 4 serve to maintain appropriate lateral spacing between the threaded reinforcing bars 1 and to share strength in the same direction.

U-shaped bolts 5 are used to loosely connect the threaded reinforcing bars 1 to the reinforcing frame 4. In the reinforcing bar cage assembly of the present invention, the reinforcing frame 4 and the threaded reinforcing bar 1 are connected as follows.
As shown in detail in FIG. 2, the U-shaped bolts 5 are fastened to hold the threaded reinforcing bar 1 at the intersection. the inner nut 6 of the U-shaped bolt 5;
Similarly, the U-shaped bolt 5 is independently fastened to the reinforcing frame 4 by the outer nut 7. Therefore, the screw reinforcing bar 1 and the reinforcing frame 4 are not fixed to each other, and a bundling structure can be formed that has a gap that allows the screw reinforcing bar 1 to rotate and move in the longitudinal direction.

As described above, the reinforcing bar cage assembly according to the present invention is
Threaded reinforcing bars 1 installed at regular intervals, a reinforcing frame 4 for maintaining the spacing between the threaded reinforcing bars 1 and preventing deformation, and reinforcing bars that are perpendicular to the threaded reinforcing bars 1 and have through holes at the same spacing as the threaded reinforcing bars 1. It is composed of a support frame 3. The threaded reinforcing bar 1 is held by the semicircular part of the U-shaped bolt 5 at the intersection of the threaded reinforcing bar 1 and the reinforcing frame 4, and the U-shaped bolt 5 and the threaded reinforcing bar 1 are fixed at a constant distance. As a result, the threaded reinforcing bar 1 is free in the longitudinal direction and free in the other direction within the gap between it and the U-shaped bolt 5, allowing the threaded reinforcing bar 1 to rotate or move as required for connection. In addition, with the fixing nut 2 screwed onto the screw reinforcing bar 1, the reinforcing bar support frame 3 is
The reinforcing bar support frame 3 is brought into close contact with the fixing nut 2 by passing through the through hole and turning the fixing nut 2. Fixing nut 2
is positioned so that it rests on the support frame 3 when the reinforcing bar cage is erected, thereby restraining the threaded reinforcing bars 1 in one longitudinal direction and preventing the reinforcing bars from falling during erecting.

The joining method of the present invention uses a torque joint using threaded reinforcing bars. The threaded reinforcing bar torque joint is composed of two threaded reinforcing bars to be coupled, one coupler 8, and two lock nuts 9, 10. One lock nut and coupler are screwed onto one threaded reinforcing bar, and by tightening the lock nut and coupler, the threaded reinforcing bar, lock nut, and coupler are integrated, and similarly, by tightening the other lock nut and coupler, there are two screws as a whole. The reinforcing bars are now joined. At this time, the phases of the screw threads of both threaded reinforcing bars must match. That is, the threads of one threaded reinforcing bar engage with the threads of the coupler, and the threads of the coupler mesh with the threads of the other threaded reinforcing bar, thereby enabling the coupling. Generally, if the screw threads do not match in phase, it is necessary to adjust the phase by moving one of the screw reinforcing bars in the longitudinal direction or by rotating them at the same position. For this reason, one of the threaded reinforcing bars needs to be free at least in the longitudinal direction or in the rotational direction. In the reinforcing bar cage assembly of the present invention, the reinforcing bars of the upper reinforcing bar cage block to be coupled are free in the rotational direction, and can be coupled with a torque joint using a coupler.

The reinforcing bar cages are joined using the following procedure. Match the threaded reinforcing bar end of the suspended upper reinforcing bar cage block with the threaded reinforcing bar end of the lower reinforcing bar cage block to match the phase of the screw threads. To do this, first, use a pipe wrench or the like to prevent the fixing nut on the reinforcing bar support frame from rotating, and then rotate the reinforcing bar, or rotate the fixing nut to ensure the necessary clearance between the upper and lower reinforcing bars in the torque joint. Next, rotate the upper reinforcing bar and fixing nut at the same time to match the threads of the lower reinforcing bar. After that, follow the normal torque joint procedure and complete the connection of the upper and lower reinforcing bars by tightening the coupler and lock nut. The plurality of threaded reinforcing bars provided on the reinforcing bar cage block are connected one after another by the above procedure, and the connection of the reinforcing bar cage as a whole is completed.

Note that by using similar structures in the lateral direction as needed, lateral connections can also be easily made.

(Effects of the Invention) Compared to conventional welding, the present invention eliminates the need for various controls required for welding, does not affect the weather, and reduces the time required for joining reinforcing bar cages. It is possible to reduce construction period and costs. In addition, the reduction in fatigue strength due to welding can be avoided, which improves the overall quality of the reinforcing bar cage, and since it can be designed based on the fatigue strength of the reinforcing bar base material, more economical designs are possible and highly reliable products can be obtained. It will be done.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a view showing a bundling structure of threaded reinforcing bars to a reinforcing frame in the present invention, and Fig. 3 is a perspective view showing the connection of reinforcing bar cages by conventional welding. It is a diagram. 1...Screw reinforcing bar, 1a...Horizontal bar, 2...Fixing nut, 3...Reinforcement support frame, 4...Reinforcement reinforcement frame, 5
... U-shaped bolt, 6 ... Inner nut, 7 ... Outer nut, 8 ... Coupler, 9, 10 ... Lock nut, 11 ... Reinforcement bar, 12 ... Welded part, 13 ...
Horizontal strip, 14...Welded part.

Claims (1)

[Scope of Claims] 1 Threaded reinforcing bars arranged at regular intervals, a reinforcing frame for maintaining the spacing between the threaded reinforcing bars and preventing deformation, and through holes perpendicular to the threaded reinforcing bars and having the same spacing as the threaded reinforcing bars. It consists of a reinforcing steel support frame with
A U-shaped bolt is used at the intersection of the screw reinforcing bar and the reinforcing frame to create a binding structure in which the longitudinal direction of the reinforcing bar is free and the other direction is free in the gap between the U-shaped bolt and the threaded reinforcing bar is attached to the reinforcing bar support frame. A reinforcing bar cage assembly for an underground continuous wall, characterized in that the reinforcing bar cage assembly for an underground continuous wall is formed by penetrating the reinforcing bar through a through hole and screwing a fixing nut to form a support structure in which one direction of the longitudinal direction of the reinforcing bar is restrained. 2. In a method of forming a continuous wall using reinforcing bar cage blocks whose main components are threaded reinforcing bars arranged at regular intervals, an upper reinforcing bar cage block that is next connected above a lower reinforcing bar cage block that has been temporarily constructed first is used. is suspended, the upper threaded reinforcing bar end of the lower reinforcing bar cage block and the lower threaded reinforcing bar end of the upper reinforcing bar cage block are butted individually, and each is fastened with a coupler to be integrated. Connection method for reinforcing bar cages for medium continuous walls.