JPS6053129B2 - Sheet for stable construction method of underwater structures - Google Patents

Description

[Detailed Description of the Invention] Conventionally, in areas with large waves and severe scouring, the aim is to prevent uneven settling of rubble at the base of underwater structures and to prevent scouring.
The Matsutoe method is used to lay sand prevention mats at the base, but after the mats are laid, rubble at the tips of the mats is scattered and uneven settlement occurs.

In order to eliminate such drawbacks, the present inventor proposed a flexible sheet with a protective rubble retaining member disposed on the free edge of the bag in Japanese Patent Application No. 1983 (filed on October 7, 1982). We have proposed a method for stabilizing underwater structures, which is characterized by laying a flexible sheet at the base of the underwater structure, and dumping protective rubble into the edge of the flexible sheet that protrudes from the periphery of the base.

According to this construction method, as described above, protective rubble is dumped into the protruding end of the flexible sheet laid at the base of the underwater structure from the periphery of the underwater structure.
When the protective rubble part in the underwater ground undergoes initial scouring, the protruding end of the flexible sheet is gradually buried together with the rubble due to the weight of the protective rubble, and the protective rubble serves as an anchor. As a result, the protruding end portion is anchored in the underwater ground.

At this time, since a protective rubble holding member is provided on the free edge of the sheet, the protective rubble is always firmly held on the edge of the flexible sheet, and the protruding edge of the sheet is protected from waves, etc. Therefore, even if the protective rubble is subjected to scouring, it will not be easily scattered by waves, and the tip of the rubble foundation will not collapse due to being buried in the underwater ground. As a result, the protective rubble on the sheet The rubble stones are used to strengthen the footing in a natural state, preventing tilting and subsidence due to uneven settlement caused by scouring of underwater structures due to water currents, waves, etc., and also coping with the scouring of the flexible sheet. This reduces the amount of oscillation that occurs, which reduces the chance of damage to the sheet and provides a stable anti-sand effect. In addition, the construction method has many advantages compared to the conventional anchor construction method, such as lighter equipment, no need for special equipment, better workability, and reduced construction costs.

However, the sheet made of vinyl chloride sheet etc. used in the above-mentioned stabilization method has a semicircular, U-shaped, E-gonal, etc. protective rubble holding member made of a hard vinyl chloride plate on the free edge of the flexible sheet body. Since the parts are fixed together, there are manufacturing difficulties, and there are doubts about the reliability of the parts that are fixed by welding or the like.

The present invention was proposed in order to eliminate such drawbacks, and the present invention has been proposed by arranging sheet longitudinal direction reinforcing rods whose tips are covered in a U-shape in parallel, and extending the sheet axial direction reinforcing rods over each of the reinforcing rods. The present invention relates to a sheet for stabilizing construction of an underwater structure, in which the outer circumferential surface of a flexible sheet is attached and fixed along the outer circumferential surface of a horizontally suspended reinforcing frame.

According to the present invention, as described above, a reinforcing frame is constructed by horizontally connecting a reinforcing rod in the sheet width direction to a plurality of reinforcing rods in the longitudinal direction of the sheet that are parallel to each other and whose tips are bent into a U-shape. By splicing and joining the tips of the flexible sheets along the outer circumferential surface of the frame, a U-shaped protective rubble holding member is constructed at the tips of the flexible sheets. By connecting the sheet to the reinforcing rods constituting the reinforcing frame via clips or other connecting fittings, the rubble retaining portion for protecting the tip of the flexible sheet can be easily and reliably constructed, and the retaining portion and Unlike when the flexible sheet is fixed by welding or the like, there are no problems in the reliability of the joint or in the manufacturing technique, and the manufacturing is easy and costs can be reduced.

The present invention will be described below with reference to the illustrated embodiments.

Reference numeral 1 denotes sheet longitudinal reinforcing rods each having a U-shape in which a vertical rising portion 1b1 and a horizontal folding portion 1c are sequentially bent at the tip of a main body 1a made of a metal rod or the like, and the required number of reinforcing rods are arranged in parallel. A reinforcing rod 2 in the seat width direction is fixed horizontally between the main body 1a1, the vertically rising portion 1b1, and the horizontal folding portion 1c of each reinforcing rod 1 to form a reinforcing frame.

One or more of the reinforcing frames configured as described above are arranged in parallel in the required number, and the edges of the flexible anti-sand sheet A made of vinyl chloride sheet etc. are placed along the outer peripheral surface of the reinforcing frames. The parts are bent and attached and fixed to the reinforcing rod 2 of the reinforcing frame via a fastener 3 such as a U-shaped clip to constitute the protective rubble holding part of the sheet for the stable construction method of the present invention.

Note that 4 in the figure is a through hole bored in the sheet A. The sheet for the stable construction method constructed as described above is laid at the base of an underwater structure such as a caisson, and the edge of the sheet protruding from the periphery of the base of the structure and the slope of the lower end of the base are separated. In between, protective rubble is thrown away, and the protective rubble is held by the protective rubble holding section to prevent it from dissipating.

As a result, the water bottom ground on the lower surface of the protruding end of the sheet A is exposed to water flow,
When subjected to initial scouring by waves or the like, the protruding end of the sheet is gradually buried together with protective rubble, and is finally anchored in the underwater ground.

The protective rubble on the sheet end is prevented from being scattered by water currents, waves, etc. by the protective rubble holding section. As a result, the free end of the sheet is anchored in a stable state in the earth and sand of the underwater ground, and the protective rubble on the sheet causes the base to be hardened in its natural state, and the lower part of the sheet end is This prevents the inclination and subsidence of underwater structures caused by uneven subsidence due to scouring of the submerged soil. Although the present invention has been described above with reference to embodiments, the present invention is, of course, not limited to such embodiments, and can be modified in various ways without departing from the spirit of the present invention. .

[Brief explanation of drawings]

FIGS. 1 and 2 are a longitudinal side view and a plan view, respectively, showing an embodiment of a sheet for stabilizing construction of underwater structures according to the present invention. 1... Woot longitudinal direction reinforcing rod, 2... Sheet width direction reinforcing rod, A... Flexible anti-sand sheet.

Claims (1)

[Claims] 1 Flexibility is achieved along the outer peripheral surface of a reinforcing frame in which reinforcing rods in the longitudinal direction of the sheet whose tips are curved in a U-shape are arranged in parallel, and reinforcing rods in the sheet width direction are hung horizontally across each of the reinforcing rods. A sheet for stable construction of underwater structures, which is made by gluing and fixing the outer circumferential surface of the sheet.