JPS607094B2 - Rubble foundation mound formation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming a rubble foundation mound for supporting a caisson on the seabed or the like.

Generally, when constructing a sea wall or a composite embankment by attaching a caisson to the seabed, etc., it is not possible to directly install the caisson on the seabed because the ground is uneven, sloped, or soft. Can not. For this reason, a mound is formed on the ocean floor, and a caisson is attached to the top. The intended mound was formed by throwing large rubble stones into the sea using gut ships, but the top surface is so uneven that it is impossible to install caissons.

For this reason, submersible divers level the top surface of the mound underwater. However, because the rubble is heavy and leveling is difficult, it is not possible to increase the leveling accuracy and the construction period becomes longer.
As a result, there is a problem of increased construction costs.

For this reason, a method using a leveling machine has been tried, but no sufficient effect has been obtained. Furthermore, a method of putting small crushed stones on top of a large rubble foundation mound is considered, but a considerable amount of crushed stone is required, the amount is not constant, and it is not suitable for places where the influence of tidal currents and waves is large. In other words, it is not suitable for locations with poor sea conditions.

Even if crushed stone is used, there are disadvantages such as the need for leveling work by divers. The above-mentioned disadvantages are particularly noticeable when large caissons are installed in deep water areas.

The present invention has been made in view of the above-mentioned problems and to effectively solve them.

That is, an object of the present invention is to provide a method of forming a mound with high flatness accuracy in a short period of time with simple work without requiring any leveling work.

In order to accomplish this purpose, the present invention has a frame body shaped to follow the shape of a desired mound, and is made up of an upper sheet and a lower sheet with a larger area, and a space is provided between these sheets. The mat to be formed is attached so that it can expand and contract, and while the mat remains contracted, the frame is lowered to near the top of the rubble foundation mound.Then, the mat is expanded to cover the mound, and then mortar is poured into the space within the mat. The gist is that the injection of

The construction method of the present invention will be explained in detail below with reference to the accompanying drawings.

First, in the same manner as the normal mound forming process, as shown in FIG. 1, large rubble stones 2 are dumped into the sea by a gut ship 1 to form a rubble foundation mound 3.

Once the mound 3 has been formed, the frame 6 with the mat 5 attached thereto is transported by a barge 4 or the like to above the rubble foundation mound, as shown in FIG. As shown in Fig. 3, this frame body 6 is constructed by joining angle materials or channel materials 7 in a lattice shape to form a framework, and a large number of steel rods 8 are strung between the frameworks in a lattice shape. I try to make it take shape.

The mat 5 is attached to the lower surface of the frame 6 so as to be freely vertical.

As shown in FIG. 4, this mat 5 consists of an upper sheet 5a and a lower sheet 5b.The lower sheet 5b has a sufficiently larger area than the upper sheet 5a, and these sheets 5a and 5b are connected with elastic threads 9. The sheets 5a and 5b are tied while maintaining the interval.
A space S is formed between them. A large number of pulleys 10 are fixed to the upper sheet 5a of the mat 5, and these pulleys 10 are slidably engaged with a pipe material 7 forming the framework of the frame 6. Therefore, pulley 1Q'
A rope 1 for brazing is attached here, and the mat 5 is expanded or contracted by winding up this rope 11. As shown in FIG. Let it settle to the vicinity.

At this time, the mat 5 is removed by a winding winch 13 installed in the center of the barge. By rolling up the loop 1, it is kept in a folded state at the center of the frame 6. By doing this, there is no resistance when lowering the frame 6, and the work can be done quickly. Once the frame body 6 has been lowered to the vicinity of the top surface of the mound 3, the rope 11 is rolled up by the winches 14 provided at both ends of the barge 4, and the mat 5 is unfolded to the state shown in FIG. In this state, the frame body 6 is further lowered so that the mound 3 is covered with the mat 5 as shown in FIG.

Then, since the lower sheet 5b of the mat 5 has a large area, it adapts to the unevenness of the upper surface of the rubble mound 3 and covers this uneven surface without any gaps. This state is shown in the enlarged view of FIG. Next, as shown in Figure 8,
Pull out the mortar injection tube 15 from the barge 4,
The tip of this tube [6] is inserted into the space S of the mat 5, and the space S is injected and filled with mortar.

If the mortar is hardened in this state, the lower sheet 5b' of the mat will cover the unevenness of the mound 3 without any gaps, and the upper sheet 5b will be prevented from bulging upward by a large number of steel rods 8, etc. Regardless of the shape of the upper surface of the mound 3, a mound with a flat rising surface is always formed.Although it is of course possible to leave the frame 6 as it is after forming the mound. It is also possible to separate only the frame 6 from the mat 5 and use it for forming the mound again.

As is clear from the above explanation, according to the construction method of the present invention, large rocks etc. are first thrown in to form a rubble foundation mound, and then an upper sheet and a lower sheet with a larger area are formed. A frame to which a mat that can be expanded and contracted to form a space between sheets is lowered to the vicinity of the mound while the mat is contracted, and then the mat is expanded and the frame is further lowered to form a rubble foundation using the mat. By covering the mound and then injecting mortar into the spaces in the mat, a highly flat and highly accurate mound can be obtained without any need for leveling the mound, and the work is easy and quick. Since it can be carried out within a short period of time, it is possible to shorten the construction period and significantly reduce the construction cost, and it has many advantages such as being particularly effective in forming mounds in deep water areas.

[Brief explanation of drawings]

The drawings show an example of the implementation of the present invention, and FIG. 1 is a side view showing the process of forming a rubble foundation mound, FIG. 2 is a side view showing the settling process of the frame, and FIG. 3 is a plan view of the frame. Figure 4 is a side view showing the mat attached to the frame; Figure 5 is a side view showing the mat unfolded; Figure 6 is a side view showing the mat covering the rubble mound; Fig. 7 is a partially enlarged side view of Fig. 6, and Fig. 8 is a side view showing the mortar injection process. 3...Rubble foundation mound, 5...Mat, 5a
......Upper sheet, 5b...Lower sheet, 6
・・・・・・Frame. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Cod Figure 7 Figure 8

Claims (1)

[Claims] 1. A mat consisting of an upper sheet and a lower sheet having a larger area than the upper sheet and forming a space between these sheets is attached to a frame body that follows the desired mound shape so as to be expandable and retractable, and the above-mentioned With the pine contracted, the frame is lowered to near the top of the rubble foundation mound, then the pine is expanded, the frame is further lowered to cover the rubble foundation mound with the pine, and then mortar is poured into the space of the pine. A rubble foundation mound formation method characterized by: