JPH0319323B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a construction method for temporarily constructing a pier or a bridge.

Prior Art Conventionally, the method of constructing a pier or bridge consists of the steps of constructing piers and subsequently constructing girders, and this is the same even if it is a temporary bridge.

By the way, even for temporary bridges, the work of driving the piles for the piers requires large-scale equipment, and the cost of using such equipment is also high.

To avoid this difficulty, floating piers or floating bridges have been used in the past, but these have poor horizontal and vertical positional stability and unreliable load-bearing capacity.

Purpose This invention solves the above-mentioned drawbacks of the conventional method and provides a method for constructing a hypothetical bridge that is easy to construct and has good stability and reliability.

Configuration This invention provides a buoy having a watertight elongated box-shaped structure that can float on the water surface like a ship's hull;
On the other hand, a temporary bridge member having a pile body that is engaged so as to be raised and lowered and a member that can fix this pile body to a floating girder is placed at a predetermined position, and the pile body is lowered at that position and the tip of the pile body is lowered. After grounding on the water bottom and fixing the pile body to the floating girder, by filling the watertight inside of the floating girder with water, the weight of the floating girder and water acts on the pile body, and the pile body is fixed to the water bottom. This is a method for constructing a temporary bridge that includes the steps of driving, sinking to a depth where the pile body can withstand a predetermined load, fixing the floating girder at a predetermined position on the pile body, and draining water inside the floating girder.

The basic idea of this invention is summarized as follows.

1 Fill the buoy with water, and depending on the weight of the buoy and water,
If the pile body is driven into the water bottom and the pile body stops sinking when the floating girder filled with water is completely exposed above the water surface, in this state, the sum of the self weight of the floating girder and the weight of the water is This is in balance with the supporting capacity.

2 If the water inside the buoy is drained in this state, there should be enough extra support capacity for the pile body to correspond to the weight of the water inside the buoy. This becomes the supporting capacity of a pier or bridge.

3 Furthermore, as a result of this stress, if the water in the buoy is drained and the buoy is left floating in the water, a buoyancy equivalent to the amount of water drained will be obtained, increasing the supporting capacity of the bridge or bridge. become.

Since the bridges and bridges temporarily constructed using this method are supported by piles, their positional stability is better than that of floating bridges.

A specific example of this invention will be described with reference to the drawings. FIGS. 1-a to 1-f illustrate the process of implementing this invention in a place where the water level fluctuates, such as on the coast.

Fig. 2 is a partially cutaway plan view showing the structure of a specific example of the floating girder used in the method of the present invention, Fig. 3 is a partially cutaway side view of the floating girder shown in Fig. 2, and Fig. 4 is the pile body. Figure 5 is an explanatory diagram showing the structure of the upper part of the pile body and the guide relationship.

First, as shown in FIG. 1-a, the buoy 1 is staked at a predetermined position close to the coast, and the pile body 2 is lowered so that its tip touches the seabed.

As shown in FIG. 3, a cap 3 having a pulley at the top is attached to the tip of the pile body 2, and a suspension cable 4 is installed on the nail. One end of this suspension rope 4 is adapted to be hoisted up by a winch 16.

The interior of the floating girder is separated by a partition wall 13.
It is divided into two water tanks 12, and in the center there is a pump chamber 15 equipped with a water supply and drainage pump 11, a water intake valve 6, and a water supply and drainage valve 7 communicating with each water tank 12. Water supply and drainage pump 1
From 1 onwards, a water supply and drainage pipe 5 is connected to a water supply valve 8 provided on the partition wall 13 of each water tank and an overall drain valve 9, and the water supply and drainage to each water tank can be controlled by these valves and the pump. .

The pile body 2 is attached by a pile guide 14 attached to the outer wall of the floating girder 1 so as to be movable up and down.

When the grounding of the pile body 2 and the erection of the suspension rope 4 are completed, the water intake valve 6 is opened to introduce water into the pump chamber 15, and the water supply and drainage valves 7 of each water tank are opened and each water tank 12 is opened.
When water is introduced into the vessel, the floating girder 1 begins to sink as shown in Figure 1-b. When the required amount of water has entered the water tank 12, the water intake valve 6 and the water supply/drainage valve 7 are closed.

When using the tide level, carry out the work up to this point at high tide, and after that, with the suspension rope stretched,
As shown in Figure-c, the tide is low. At this time, the total weight of the floating girder 1 and the water that has entered the water tank 12 acts on the pile body 2, so that the pile body 2 is driven into the bottom of the water.

In the case of inland water where fluctuations in the tide level are small or not at all, the action on the pile body is the same if the winch 16 is activated to wind up the suspension cable 4 and raise the floating girder 1 above the water surface.

The balance of the floating girder 1 is maintained by operating the winch 16 until the sinking of the pile body 2 is stabilized. At this time, the water weight in each tank 12 is finely adjusted by operating the water supply and drainage valve 7, water supply and drainage pump 11, and water supply valve 8 to each tank, and the horizontal load of the buoy 1 and the load on each pile are adjusted. Adjust.

Once the sinking of each pile has stabilized, drain the water.
To do this, open the suction/drainage valve 7 and drain valve 9 of each tank, operate the pump 11 while introducing water into the pump chamber 15, and drain the water flowing out from each tank 12 to the drain port 1.
Discharge from 0.

The stake driving and floating girder preparations are now complete. After this, depending on the usage situation as a pier or bridge, loosen the suspension cables and lower the floating girder as shown in Figure 1-d until a part of it is submerged in water, which corresponds to the displacement of that part. The more you do this, the more power you have to withstand the load.

When the pier or bridge thus temporarily constructed is to be removed after use, the pile bodies 2 are cut. When the lower guide 14 of the float is above the cut surface, the float 1 can be removed.

As for the work procedure at the site, first, the water level is lowered by taking advantage of low tide, and the pile body 2 is cut in a state where the cut portion is above the water surface (position m in Fig. 1-e).

After cutting the pile body, the floating beam is raised using the high tide, and when the position of the lower guide 14 is higher than the top of the cut pile body, the floating beam is lifted from the pile body 2, as shown in Fig. 1-f. Remove digit 1.

Another procedure is to sink the floating girder 1 and cut the pile body, then float the floating girder and position the lower guide higher than the top of the cut pile body to remove the floating girder from the pile body. You may leave.

Effects As explained above, according to the present invention, it is possible to proceed with piling work at the same time as girder construction without carrying out large-scale piling work, and moreover, it is possible to easily construct a temporary bridge with good stability. Can be installed and removed.

[Brief explanation of the drawing]

Figures 1-a to 1-f are explanatory diagrams showing the steps of a specific example of the present invention, and Figure 2 is a partially cut plane showing the structure of a specific example of the floating girder used in the method of the present invention. Figure 3 is a partially cutaway side view of the floating girder in Figure 2 above, Figure 4 is an explanatory diagram showing the structure of the upper part of the pile body, and Figure 5 is an explanatory diagram showing the relationship between the pile body and the guide. It is a diagram. 1...Floating girder, 2...Pile body, 3...Cap, 4
... Suspension cable, 5 ... Water supply and drainage pipe, 6 ... Water intake valve, 7
... Water supply and drainage valve for each water tank, 8 ... Water supply valve, 9 ... Overall drainage valve, 10 ... Drain port, 11 ... Water supply and drainage pump, 12 ... Water tank, 13 ... Partition wall, 14 ...
...Pile guide, 15...Pump room, 16...Winch, A...Scale indicating tide level, m...Pile cutting position.

Claims (1)

[Claims] 1. A buoy with a watertight elongated box-shaped structure that can float on the water surface like a ship's hull, a pile body that is engaged to the buoy so that it can be raised and lowered, and a member that can fix this pile body to the buoy. The temporary bridge member with The weight of the floating girder and water acts on the pile body, the pile body is driven to the bottom of the water, and after the pile body sinks to a depth that can withstand the specified load, the pile body floats to a specified position. A method for constructing a temporary bridge that includes the steps of fixing the girder and draining water inside the floating girder.