JP2772513B2 - Leader for sand pile formation and its expansion and contraction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leader for guiding and supporting a hollow pipe provided with a hollow pipe for forming a sand pile, and a method for expanding and contracting the leader.

[0002]

2. Description of the Related Art In recent soil improvement works performed using a sand pile driving ship, the construction site has been developed offshore, and the soft layer to be improved becomes deeper. Are also increasing in size. However, the height of the leader that suspends the hollow pipe for sand pile formation is also limited by the location, such as height restrictions due to bridges such as the Seto Bridge and Akashi Kaikyo Bridge, and height restrictions due to takeoff and landing of aircraft near the airport. become.

Therefore, when passing under a bridge or around an airport, long leaders also need to be lowered.
Especially, when passing under a bridge to move a construction site or evacuate a typhoon, the leader only needs to be lowered temporarily. The need for a crane ship, which is time consuming and enormous, requires a way to easily adjust the height of the leader.

[0004]

SUMMARY OF THE INVENTION According to the present invention, it is possible to easily adjust the height of a leader longer than a hollow pipe for forming a sand pile, and to securely fix the leader at a predetermined height. The present invention proposes a sand pile forming leader and a method of expanding and contracting the leader.

[0005]

SUMMARY OF THE INVENTION According to the present invention, when the leader is extended up and down by a known pin roller jack-up device with the upper part of the leader being doubled inside and outside, the leader is extended to perform sand pile forming work. Turns the flange attached inside the outer main leader inward,
The swivel flange is fixed to a recess provided below the extended inner leader, and when the leader is shortened, for example, when passing under a bridge, the swivel flange is raised to lower the inner leader. Things. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory side view showing an upper part of a leader according to the present invention in an extended state. Reference numeral 1 denotes a flat square main leader, for example, a height of 40 to 70 m and a sand pile. It is erected at the front end of the casting boat. Reference numeral 2 denotes a flat square inner leader which can move up and down inside the main leader 1 and has a pulley on its head for hanging a wire 17 for suspending a hollow pipe (not shown) for forming a sand pile. A top sheave 3 is attached, and the length of the leader 2 is, for example, 10 to 15
m.

On a mounting table 4 protruding from the upper end of the rear surface of the main leader 1, for example, a rotary driving device 5, a speed reducer 6, and a pin roller type pinion 7 as disclosed in Japanese Utility Model Laid-Open Publication No. 1-68389. The pinion 7 is engaged with a rack 8 provided in the center of the rear surface of the inner leader 2 in the length direction thereof, and the pinion 7 is driven by the driving device 5 to drive the inner pinion. The reader 2 is configured to move up and down, thereby expanding and contracting the height of the entire reader.

Reference numeral 9 denotes recesses formed on both front and rear sides below the inner reader 2. Reference numeral 10 denotes an upper surface of a mounting plate 11 which is horizontally projectingly fixed to the front and rear inner surfaces of the main reader 1 below the pin roller jack-up device. The inner leader recess 9 is formed by two rotating flanges which are mounted on the shaft
The size is such that the turning flange 10 can freely turn in the vertical direction from the upright state to the horizontal state.

However, for example, when performing sand pile formation work,
When the leader is extended, the two front and rear revolving flanges 10 are tilted horizontally inward, and are bolted to the mounting plate 11 inside the main leader 1 for supporting the same. It is also fixed to the upper bottom part 9a by bolts 14 (see FIGS. 1 and 2). Thus, the full heavy load during the sand pile forming operation is received by the two front and rear turning flanges 10.

When the leader is extended, the inner leader 2 is raised by the pin roller jack-up device as described above, and if the lower bottom 9b of the inner leader recess 9 comes close to the mounting plate 11 in the main leader 1, It is possible to secure a space for turning the upstanding swivel flange 10 toward the inner leader recess 9, and then slightly lower the inner leader 2 to lie down horizontally so that the upper surface of the swivel flange 10 is above the recess 9. When it comes into contact with the bottom 9a, it is fixed in the leader extended state by the bolts 13 and 14 as described above.

When lowering the height of the leader, for example, when passing under a bridge, the turning flange 10 which is now horizontal is inverted by the lower bottom 9b of the inner leader recess 9.
, The inner leader 2 is slightly raised to secure the turning space of the turning flange 10, and then turned upward so as to separate from the inside of the recess 9, and the flange 10 is moved inside the main leader 1. It stands on the mounting plate 11 (see FIG. 2).

Thus, the inner leader 2 can be lowered in the main leader 1 by the driving of the jack-up device without being obstructed by the turning flange 10, so that the flange 15 at the upper end of the inner leader 2 is It is lowered until it comes into contact with the brim plate 16 at the upper end (see FIG. 4). In some cases, sand pile formation work may be performed even in this leader shortened state. In this case, both upper and lower brim plates 15,
16 are bolted together.

[0013]

As described above, the sand pile forming leader of the present invention is expanded and contracted by the well-known pin roller jack-up device. The jack-up device includes the inner leader 2 and the top sheave 3 at the head of the device. It is sufficient if the leader has the ability to raise and lower the total weight. The heavy load when the leader is extended to perform the sand pile formation work is received by the swiveling flange 10 which is horizontally turned, and the heavy load when the leader is shortened is the main leader. Since the jack-up device is received by the collar plate 16 at the upper end, the size of the jack-up device can be reduced in size and weight, and the height of the leader can be reduced very easily and in a short time. It is easy to fix in the state, and has an economically excellent descent.

[Brief description of the drawings]

FIG. 1 is an explanatory side view showing a state in which a sand pile forming leader according to the present invention is extended.

FIG. 2 is an enlarged side explanatory view of a main part of the sand pile forming leader according to the present invention in an extended state.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is an explanatory side view showing a state at the time of shortening of the sand pile forming leader according to the present invention.

[Explanation of symbols]

 1-leader 2-inner leader 3-top sheave 4-installation table 5-rotation drive 6-reducer 7-pin roller type pinion 8-rack 9-recess 10-rotating flange 11-mounting plate 12-shaft 13- Bolt 14-Bolt 15-Brim plate 16-Brim plate

──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Daisuke Yuguchi 5292 Aioi, Aioi-shi, Hyogo Inside AIH AMTEC Co., Ltd. (72) Inventor Kazuo Takada 5292 Aioi, Aioi-shi, Hyogo Ai Inc.・ H.I.A.M.T.Tech. (72) Inventor: Ryokata Shigeoka 5377, Aioi, Aioi-shi, Hyogo Prefecture Inside Fujikai Industries Co., Ltd. (56) References JP-A-49-85805 (JP, A) 1-187216 (JP, A) JP-A 2-89025 (JP, U) JP-A 1-65332 (JP, U) JP-A 56-103395 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) E02D 3/10 104

Claims (2)

(57) [Claims] An upper part of a leader for supporting a hollow pipe for sand pile formation is formed inside and outside, and a pin roller jack-up device is installed outside an upper end portion of an outer main leader. A pin roller type pinion to be engaged with a rack provided on the outside of the inner leader in the length direction thereof so that the inner leader can be moved up and down, and the front and rear inner surfaces of the main leader below the jack-up device are arranged vertically. The mounting plate, which is pivotally pivoted and can be fixed in the horizontal direction, is fixed to the upper surface thereof by projecting and fixed, and the lower and front sides of the inner leader are formed with recesses large enough to pivot the pivot flange. A leader for sand pile formation. 2. The upper part of the leader supporting the hollow pipe for forming sand piles is configured to be double inside and outside, and the inner leader can be moved up and down by a pin roller jack-up device. On the lower front, front and rear inner surfaces, mounting plates are provided that are protrudingly fixed to the upper surface, with a pivoting flange that can pivot vertically and can be fixed in the horizontal direction on the upper surface. When the leader is extended, the lower bottom of the recess of the inner leader raises the inner leader to the position of the mounting plate of the main leader, and the revolving member stands on the mounting plate. Swivel the flange into the recess and turn it sideways, fix the flange and the mounting plate with bolts, and then lower the inner leader slightly to secure the swivel flange to the upper bottom of the recess. Also, when shortening the leader, once the inner leader is slightly raised, the horizontally fixed swiveling flange is brought close to the lower bottom position of the inner leader recess, and the flange is swung upward to be separated from the inside of the recess. A method of telescopically fixing a leader for sand pile formation, wherein the upper leader plate is later lowered until the brim plate at the upper end of the inner leader comes into contact with the brim plate at the upper end of the main leader.