JPH0694666B2 - Construction method of rubble mound - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method of constructing a rubble mound that can be constructed even in an offshore location where the sea waves are large.

[Conventional technology]

Conventionally, in order to build offshore structures such as breakwaters, a rubble mound is made on the seabed at the installation position, but to construct the rubble mound, a rubble mound is to be built in the rubble mound creation area with a gut ship. After throwing in, the rubble stone for surface finishing was thrown in further, the weight was further attached to the crane ship, and the weight was dropped to level the rubble mound.

However, in places with large waves, the hull of a crane ship sways due to the waves, and the weight cannot fall to a position on a specified rubble. There was a problem that leveling work was not performed.

[Problems to be Solved by the Invention]

The present invention has been made in order to solve the above conventional problems, and even in a place where the waves are large, an accurate rubble mound can be easily constructed, and a rubble mound construction method that can be efficiently performed is provided. Is the problem to be solved.

[Means for Solving the Problems]

As a means for solving the above problems, the method of constructing a rubble mound of the present invention is, at the tip of a rubble mound formation area, after laying a caisson that can be settled and floated, and then put a rubble stone on the rubble mound formation area. After throwing in, throw a rubble for surface finishing with a crawler crane installed on the upper stage of the caisson, and after leveling the rubble mound with a weight attached to the crawler crane, raise this caisson and appropriately Move it to a different position and sunk it,
It is characterized by repeating the above-mentioned procedure, and the loading of rubble for surface finishing and the leveling of the rubble mound by the weight are stable under the condition of a crawler crane on a caisson fixed on the seabed. Done in.

In addition, as a caisson that can be sunk and floated used during the above construction, using a caisson consisting of a lower caisson that can be poured and drained and an upper steel pipe structure makes it possible for waves to pass through the upper steel pipe structure and the effects of waves. Is preferred, which is preferable.

〔Example〕

An example of constructing a rubble mound by the construction method of the present invention will be described below with reference to the drawings. FIG. 1 is a side view for explaining a situation at the time of averaging rubble stones showing an example of construction in one embodiment, and FIG. FIG. 5 to FIG. 5 are a series of side views showing the construction procedure of the rubble mound.

First, the caisson 1 used in this construction example is, as shown in FIG. 1, a lower caisson 3 capable of pouring and draining inside and steel pipes 2A at equal intervals standing on the lower caisson 3.
It consists of the upper steel pipe structure part 2 consisting of, and each steel pipe 2A is strongly reinforced by braces 2B and horizontal braces 2C, and when this caisson 1 is finally used as a main body structure such as a breakwater, Each of the steel pipes 2A has an insertion groove 5 for inserting a concrete slab for partitioning to fill the inside with filling material.
The fender 4 is attached near the water surface W.

The lower caisson 3 is poured and drained in the plurality of steel pipes 2A of the upper steel pipe structure 2. The upper end of the steel pipe 2A is provided with a lid that can be opened and closed, and the lower end thereof is a caisson. It opens into 3.

Further, an upper stage 6 is provided on the caisson 1 so as to be above the water surface W, and a rubble 7 for finishing the surface layer is placed on the upper stage 6 and a crawler crane 8 is provided. Is installed.

Next, a procedure for constructing a rubble mound using the caisson 1 will be described in the order of FIGS. 2 to 5.

First, as shown in Fig. 2, the caisson 1 is sunk by pouring water into the lower caisson 3 on the seabed B at the tip of the rubble mound formation area, and then the rubble 11 is laid by the gut ship 10 or the like. It is put on the seabed B.

In this case, the caisson 1 must be moved and sunk in the lower caisson 3
The inside is drained, the caisson 1 is floated, moved to a predetermined position by an anchor, and water is poured into the lower caisson 3.

Next, as shown in FIG. 3, the rubble 7 for finishing the surface which is transported to and placed on the upper stage 6 of the caisson 1 is loaded by the crawler crane 8 installed on the upper stage 6 as shown in FIG. 11 Put in the specified position.

After that, the weight 13 is attached to the crawler crane 8 and, as shown in FIG. 4, the rubble mound is leveled from the top surface rubble 7 for finishing the surface.

As described above, when the leveling of the prescribed rubble mound formation area is completed, the inside of the lower caisson 3 is drained and the caisson 1 is levitated, moved to an appropriate position and laid down as shown in FIG. The rubble mound is constructed by repeating the procedure from Figure 2.

Furthermore, after all leveling work is completed, caisson 1
Is installed on the rubble mound, and the filled sand is poured by slurry transportation through the steel pipes 2A in the lower caisson.
A concrete plate for partitioning is inserted into the insertion groove 5 provided in each steel pipe at each side end of the upper steel pipe structure part 2 to close the gap between the steel pipes and fill the filling material with caisson 1 to form a breakwater. It is also possible to use it as a body structure of.

In addition, in the above-mentioned construction example, the upper steel pipe structure portion 2 is provided above.
By using the caisson 1 having the lower caisson 3 capable of pouring and draining downward, the structure is made so that waves can easily pass therethrough so that the resistance to waves is reduced. The rubble mound construction method of the present invention can be applied to any caisson such as an upper and lower caisson that is not limited to the above and can be set and floated by pouring and draining the inside of the caisson body.

〔The invention's effect〕

As explained above, according to the construction method of the present invention, the loading work and the leveling work of the surface finishing rubble to be put on the rubble are performed from the upper stage of the caisson fixed on the seabed, so that the waves The effect is that it can be performed accurately and efficiently even in a large place.

Further, if the caisson 1 having a structure through which waves pass like the upper steel pipe structure portion is used, the resistance of the caisson to waves is reduced, and the structure of the caisson can be reduced accordingly, which is economical, and in this case Further, since the steel pipe of the upper steel pipe structure can be used for pouring and draining for floating, there is an advantage that the work of pouring and draining becomes easy.

Furthermore, if the caisson is used as the main body structure after the leveling work is completed, the rubble mound construction equipment is diverted to the main body structure, which is economical.

[Brief description of drawings]

FIG. 1 is a side view for explaining the situation at the time of averaging rubble stones according to an embodiment in which a rubble mound construction method of the present invention is used, and FIGS. 2 to 5 show the construction procedure according to FIG. It is a series of side views. 1 ... Caisson, 2 ... Upper steel pipe structure part, 3 ... Lower caisson, 6 ... Upper stage, 7 ... Surface finishing stone,
8 ... crawler crane, 11 ... rubble, 13 ... dead weight.

Claims (2)

[Claims] 1. A caisson capable of being settled and floated at the tip of a rubble mound formation area, and after throwing rubble into the rubble mound formation area, by a crawler crane installed on the upper stage of the caisson. After throwing in the rubble for surface finishing, and leveling the rubble mound with the weight attached to the crawler crane, float the caisson and move it to an appropriate position to sunk it, and repeat the above procedure. Construction method. 2. The method of constructing a rubble mound according to claim 1, wherein the caisson which can be settled and floated is a caisson composed of a lower caisson capable of pouring and draining and an upper steel pipe structure.