JPH0548811B2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> The present invention relates to a method for stopping water at joints of steel materials for cofferdams, and in particular, a method for preventing water-stopping materials from leaking outside from the joints. Regarding the water stop method.

<<Conventional technology>> As is well known, in foundation work for bridge piers, etc., cofferdams are constructed above the water surface and construction is carried out with the water inside the coffers excluded.As a type of cofferdam, There is a method of construction by sequentially connecting steel materials such as steel pipes or H-shaped steel.

In the steel materials used for such cofferdams, joints that are engaged with each other are usually fixedly installed in each steel material in advance, an example of which is shown in Japanese Patent Publication No. 59-44462, for example.

In the joint structure disclosed in the above publication, annular steel pipe sheet piles are used as the steel material, and a box-shaped joint having a slit-shaped opening is fixed on the side surface of one of the steel pipe sheet piles that are interconnected. A T-shaped joint that is inserted into the box-shaped joint through the opening is fixed on the side surface of the other steel pipe sheet pile,
When the steel pipe sheet pile is penetrated into the ground, these joints are engaged with each other when it is driven.

Once a cofferdam of a predetermined length has been constructed, a hardening water-stopping material such as mortar is injected into the joint to ensure the water-stopping properties of the cofferdam. had the problem explained below.

≪Problems to be solved by the invention≫ In other words, when driving steel pipe sheet piles, a guide such as an H-shaped steel is installed in order to drive the steel pipe sheet piles along a set line, and the driving is performed along this guide. However, since the joint structure is a T-shaped joint that is inserted into the inside of the box-shaped joint through the opening, it is difficult to cast unless a certain distance is provided between the opening and the T-shaped joint. become.

However, when such a gap is provided, there is a problem in that the water stop material injected into the joint leaks to the outside from the gap.

This invention was made in view of the above-mentioned conventional problems, and its purpose is to provide a joint for steel materials for cofferdams that can reliably prevent leakage of the water stop material injected into the joint. The purpose of the present invention is to provide a method for stopping water in the area.

≪Means for Solving the Problems≫ In order to achieve the above-mentioned object, this invention penetrates into the ground by connecting them through joints, and injects a hardening water stop material into the joints. In a water-stopping method for steel materials for cofferdams such as H-type steel, I-type steel, and steel pipes, one end of a pair of L-shaped aggregate members is fixed at a predetermined distance on the outer surface of one of the mutually connected steel materials, A box-shaped joint having a slit-shaped opening between the other ends thereof, and a T-shaped joint that is fixed to the outer surface of the other steel material and inserted into the box-shaped joint through the opening. , a flexible annular member whose diameter is expandable and which is closed at one end is disposed on either the angle member or the T-shaped joint, and when the water stop material is injected, a fluid is applied to the annular member. It is characterized by supplying and expanding the diameter.

<<Operation>> According to the water-stopping method for a joint configured as described above, when a water-stopping material is injected, fluid is supplied to the flexible annular member to expand its diameter, and the outer surface of the flexible annular member becomes a T-shaped joint or an angle member. Since they abut, the curable water stop material injected into the joint is prevented from leaking.

<<Example>> Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the water-stopping method for a joint for steel materials for cofferdams according to the present invention.

The water stop method shown in the same figure is an application of the present invention to a steel material composed of H-shaped steel.
The shaped steels are connected to each other via joints 10 and are driven into the ground.

The structure of the joint part 10 includes a box-shaped joint 4 fixed to the outer surface of a flange 12 of one H-shaped steel A that is interconnected, and a box-shaped joint 4 fixed to the outer surface of a flange 16 of the other H-shaped steel B. It is generally composed of a T-shaped joint 18.

The box-shaped and T-shaped joints 14, 16 extend along the longitudinal direction of the H-beams A, B over their entire lengths.

The box-shaped joint 14 includes a pair of angle members 20,
20, angle members 20, 20 are placed at a predetermined interval, and one end thereof is connected to a flange 1, respectively.
2 to define a joint space 22 with a rectangular cross section, and a slit-shaped opening 24 is provided on the central axis of the flange 12 in the width direction.

A pair of ribs 28, 28 are protruded from the inner surface of the outer end of each angle member 20, 20, and an expansion member made of a flexible member such as rubber is provided between each rib 28, 28. A hollow annular hose 30, 30 whose lower end is closed is held between the hoses.

When the H-beams A, B... are connected to each other via the joint part 10 and driven into the ground, the inside of the joint space 22 is cleaned with jet water or the like to remove earth and sand, and then the injection pipe 32 is installed, and a curable water stop material 34 such as grout is injected.

At this time, fluid such as compressed air and water is supplied to the hose 30.

As a result, the hose 30 has ribs 2 on both sides.
Since the hose 30 is held between the hoses 8 and 8, its diameter expands only toward the T-shaped joint 18, preventing it from expanding laterally, and the outer surface of the hose 30 comes into contact with the joint 18, closing the opening 24.

When the water stop material 34 is injected as described above, leakage of the water stop material 34 is reliably prevented, contamination with seawater, etc. is eliminated, and the water stop material 34 is sufficiently filled into the joint space, and when it hardens, it becomes strong. Provides waterproof properties.

Note that the injection pipe 32 may be attached in advance to either the T-shaped joint 18 or the flange 12 of the H-shaped steel A;
When driving and penetrating the shaped joint 18, its movement in the connection direction is restricted, thereby preventing the penetration direction of the H-shaped steel B from being inclined diagonally with respect to the connection direction, and reducing penetration resistance. .

Furthermore, it is of course possible to arrange the hose 30 on the T-shaped joint 18 side.

Furthermore, the steel material for cofferdams may be not only H-shaped steel but also steel pipe sheet piles.

<<Effects of the Invention>> As explained above in the embodiments, according to the method for stopping water at the joint of cofferdam steel materials according to the present invention, leakage of the water-stopping material injected into the joint to the outside is ensured. Since it can be prevented, problems such as water pollution will also disappear.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the water stopping method according to the present invention. 10...Joint part, 12...Flange, 14...
Box-shaped joint, 16...Flange, 18...T-shaped joint, 20...Angle material, 22...Joint space, 2
4...opening, 28...rib, 30...hose,
34...Water stop material.

Claims (1)

[Claims] 1. In a water-stopping method for cofferdam steel materials such as H-type steel, I-type steel, and steel pipes, which are penetrated into the ground by connecting each other through joints and injecting a curable waterstop material into the joints, One end of a pair of L-shaped angle members is fixed at a predetermined distance on the outer surface of one of the steel members to be connected, and a slit-shaped opening is provided between the other ends of the box-shaped joint, and the other end is fixed to the outer surface of the steel member. and a T-shaped joint that is fixed to the outer surface of the steel material and inserted into the box-shaped joint through the opening, the enlarged diameter having one end closed to either the angle member or the T-shaped joint. A joint part for steel materials for cofferdam work, characterized in that a flexible annular member is provided, and when the water stop material is injected, a fluid is supplied to the annular member to expand the diameter of the annular member. How to stop water.