JPH02120418A - Foundation construction method for marine construction - Google Patents

Abstract

PURPOSE:To improve work efficiency and to shorten a construction period to reduce a cost by manufacturing hollow elements having a shape of slitting a marine construction in the case of completion, boring pile guide holes in them and providing joint holes on both sides of each of them. CONSTITUTION:Hollow elements 2 with a floating body construction having a shape of splitting a marine construction in case of completion and having pile guide holes bored in them as well as forming joint holes 6 on both sides of each of them are manufactured, and they are towed to installation places to pour water into the hollows from a water supply hole 7 until they reach near to neutral buoyance, then they are temporarily landed on the sea-bottom. After that, the adjacent elements 2 are temporarily connected to each other with a joint member 5 lying across the joint holes 6, and bearing piles 15 are driven from the pile guide holes 4 to fix the elements 2. According to the necessity, water or filler is filled into the hollow and, at the same time, mortar 16 is filled into the joint holes 6 by means of a grouting and the like, and the whole is stabilized to complete the marine construction.

Description

[Detailed Description of the Invention] I. Field of Industrial Application] This invention relates to a method for constructing foundations for offshore structures, and in particular, a method for constructing foundations for offshore structures, and in particular, a method for constructing foundations for offshore structures. This relates to a construction method for the foundation of an offshore structure, in which the structure is towed to the site and constructed.

[Prior art] Japanese Patent Application Laid-open No. 61-23 regarding conventional construction methods for underwater structures
The one published in Publication No. 3132 is known. In this method, the offshore structure was divided horizontally into blocks, and the blocks were sequentially lowered from the bottom and stacked on top of each other, and the spaces between each block were made liquid-tight, and at least the upper and lower joints between each block were drained. After that, the blocks are joined together.

[Problem to be solved by the invention] The above conventional construction method uses a method in which the marine structure is divided into the required number of blocks to form blocks, and the blocks are stacked 1n sequentially from the lower side. Maintaining liquid tightness between each block,
It is also necessary to provide drainage.

Therefore, the means for connecting each block becomes complicated, resulting in poor workability. In the case of particularly long structures, it is extremely difficult to connect the upper and lower parts of the blocks divided into the required number of blocks in the horizontal direction, resulting in high costs. Therefore, a technical problem arises that must be solved in order to improve workability, shorten the construction period, and contribute to cost reduction.This invention aims to solve this problem. .

[Means for Solving the Problems] This invention was proposed to achieve the above object, and consists of forming elements obtained by vertically dividing a completed marine structure into a d-body structure, Furthermore, the elements are provided with conductive holes vertically extending through them, and joints with adjacent elements are provided at each divided portion, and the elements are transported to the seabed surface at the installation point, and then After that, water is poured into the hollow part of the element to a state close to neutral buoyancy, and the element is temporarily brought to the bottom of the seabed.Furthermore, the adjacent elements are temporarily brought to the bottom in the same manner, and the adjacent elements are temporarily connected. After that, support piles are driven through the pile guide holes of each element, water or filler is injected into the hollow part of each element as necessary, and the joint parts are connected by means such as grouting. The present invention aims to provide a method for constructing foundations for offshore structures, which is characterized by the following.

[Effects] Each element is manufactured on land in the required number in the shape of a vertically divided offshore structure when completed, and the element is configured to have sufficient buoyancy so that it becomes a floating body. Therefore, when the element is towed to the planned installation point at t7 or U and reaches the planned installation point, water is poured into the hollow part of the element until the element is close to neutral buoyancy, causing it to land softly on the bottom. Furthermore, an element adjacent to this element is temporarily attached in the same manner as described above. Then, the alignment of adjacent elements is adjusted and temporarily joined at the joint portion. At this time, the adjustment operation is performed in a neutral buoyancy state of the element, making it extremely easy. In this manner, in order to ensure that the combined elements are sufficiently stable during temporary installation, it is also possible to further stabilize the combined elements by pouring water once to ensure stable bottoming of the entire element. After that, support piles are driven through the drag holes provided in each element to fix each element to the seabed, and water or filler is injected into the surplus part of the hollow part to increase gravity, and furthermore, each element is fixed to the seabed. The joint part of the element is solidified integrally by means such as glass or cloud injection,
This is how the foundations of offshore structures are constructed.

Also, as mentioned above, using the buoyancy of the element,
It can also be fixed using the above-mentioned support piles that are placed on the soft layer of the seabed. Furthermore, by attaching a jack or the like between the flange provided at the head of the support pile and the head of the element and pressing it, the element sinks and becomes buried in the soft layer. It can also be stabilized.

Therefore, in each of the above cases, excavation of the soft layer is not required in either case.

[Example 1] Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. Figures 1 to 5 show respective embodiments of elements manufactured by vertically dividing the marine structure. Figure 1 is a perspective view of element (2) of the first embodiment. However, the element (2) is formed in the shape of a side wall, one of which is formed in a hollow part (3) as shown in the cross-sectional view of FIG. -1] is provided below.Furthermore, on both sides of the element (2) where it is divided, joint members (5) (5) shown in Fig. 7 are inserted from above to the F section. Joint holes (6) (6) are provided for pouring.The joint holes (6) (0) form a (C) shape when adjacent elements (2) (2) are joined. is formed and the joint member (5) is cast across both sides to form the joint part (0), so both joint holes (6) ( The joint member (5) that spans over and connects the joint member (5) is formed in a planar (V) shape.

In addition, the guide pile holes (4) (4) and the joint holes (6) (6) are
The element (2) is configured to maintain the buoyancy of the element (2) due to the hollow portion (3) by not communicating with the hollow portion (3).

Next, the element (2a) shown in FIG. 3 will be explained.

This has a rectangular block shape as a whole, and the joint holes (6a) (6a) provided on both sides thereof are formed in a T-shape, and when the two elmmen h (2aH2a) are joined, I -1 shape. Two guide holes (4a) (4a), (4a) (4a) are penetrated in the vicinity of the joint hole (6aH6a) before and after the joint hole (6aH6a), respectively.

Similarly to element (2) in Figure 1, the guide pile hole (4a) and joint hole (6a) are configured so as not to be electrically connected to the hollow part of the element (2). It is.

Next, the element (2h) shown in FIG. 4 will be explained. This element (2b) is the element (2b) in Figure 1.
), but the guide holes (4) (4) are provided in the lower portions of both sides, and the joint holes (6b) provided in the divided portions on both sides. (6b) is formed into a substantially circular shape, and the adjacent element (2b)
It is designed so that it will become a Kuruma Akira when joined with.

In addition, Niremen l-(2C) in Figure 5 is a marine structure (1
) corresponds to a corner when constructed in a rectangular shape, and therefore it is configured in the shape of HIi Hole (4X
/I) and joint, -? L (6) (6) is exactly the same as element (2) in FIG. However, the shape 11ffl and configuration of element (2) (2aH2bH2e) described in - should not be limited to those of the above embodiment.

Note that the symbols (7) (7)... are elements (2) (2a
Shows the water injection hole provided on the 1st side of H2b) (2c).

The construction method of the present invention using the element described above will be explained with reference to FIGS. 6 and 7. Figure 6 (^) shows the ocean state before application, (8) is the water surface, (9) is the soft layer, (1u)
is the support layer. As shown in Figure (B), a sand layer (11) is formed on the first side of the soft layer (9) at the planned installation point, and the land is leveled. Therefore, the element was replaced with the sand layer (
11) The elements are placed one after another on the upper surface of the sand layer.Since the elements are formed hollow and have sufficient buoyancy, it is natural that they can be towed to the site by wind. (11) When towed to the upper surface of the element, the water injection hole (7) (7) provided on the first side of the element (7)... is allowed to sink while injecting water as appropriate to a state closer to neutral 17 force,
As shown in the figure (C), a temporary bottom ridge (7) is placed on the -1- face of the sand layer (11).

Next, the element to be joined to the chain plate ('1 bottomed element) is temporarily attached to the top surface of the sand layer (II) in the same manner as described above, thereby forming a vertically divided marine structure (1). Arrange each element into 112 columns.At this time,
When aligning each element, use the above 17 methods (,
The alignment adjustment operation is facilitated because it is temporarily attached to the bottom. In this way, each planar joint member (5) shown in FIG. 7(^)(It)(C) is cast from above, spanning the joint hole formed by the adjacent element (17).

This pouring operation is carried out using the vibrohammer H installed on the hoist (1st floor) in the -L order shown in Figure 6 (D) and (E).In this way, each element is temporarily joined. However, at this time, i' may be seated on the -1- plane of the sand layer (11) while pouring water into the hollow part (3) of each element again. As shown, one support pile (one (1)
The offshore structure (1) is completed by pouring... and fixing each element, but if necessary, water or filler is injected into the hollow parts (3) (3)... of each element. At the same time, mortar (10) is injected into the joint hole using a method such as grouting to harden and stabilize the whole. It is also possible to make a judgment.

Therefore, when the support pile (+!'J (F19...) is driven, the support pile (1→(1...
The support piles (F9) are driven at a deep depth (10) to stably fix each element to the seabed, but the elements can also be made to maintain an appropriate buoyancy and tightened at the bottom of the tube.Furthermore, the support piles (F9 (If you attach a jack etc. between the flange provided on the head of 1'19... and the head of the element and press it, the element will sink and become embedded in the soft layer (9). In both of these two cases, excavation of the soft layer (0) is not required.

It should be noted that the present invention can be modified in various ways without departing from the spirit of the invention, and it goes without saying that the present invention extends to such modifications.

[Efficacy of invention! I! 1. The present invention has the following effects: Δl111': The structure is divided to form a valley element, and this element is formed into a hollow shape to maintain sufficient buoyancy. is the same as the conventional example, but the difference from the conventional example is that an element is manufactured in which the marine structure is vertically divided, and this element is provided with conductive holes at the top and bottom. The point is that joint holes are formed on both sides of the part. Therefore, as in the past, the tube is towed to the site using buoyancy, water is injected into the hollow part as appropriate, and the bottom is allowed to land on the seabed that has been leveled in advance.However, since water is injected to a state close to neutral buoyancy, the bottom of the tube is gentle. This makes it easier to temporarily land at the destination point. Furthermore, the adjacent elements are sequentially placed at the bottom of the tracheal tube in the same manner, but as described above, since the elements are placed at the bottom of the tracheal tube while retaining buoyancy, it is easy to adjust the alignment of the entire elements. In addition, the operation of driving support piles into the guide hole is extremely easy and reliable because it is performed from the top of the element protruding above the water surface. In addition, by vertically dividing the structure, it is possible to maintain the stability of the structure even during construction, and it is adaptable to changes in construction due to changing conditions.Four points: Due to the miniaturization, mechanized construction is easy. Furthermore, the elements can be mutually connected, and other advantages of the N-coupled structure can be obtained in a short period of time.This is an invention that brings about various remarkable effects.

[Brief explanation of the drawing]

The figure shows one embodiment of the present invention, and FIGS. 1, 3, 4, and 5 are perspective views of elements showing respective embodiments, and FIG. - A cross-sectional view, Figure 6 (80B) (C) (D) (E) (F) is an explanatory diagram showing the construction procedure, Figure 7 (A) (II) (C) is the joining of elements Partially cutaway plan view showing the section, Fig. 8(A) (
n) is a plan view showing the marine structure. (1)... Marine structure (2) (2aH2bH2c)-: I-lement (3)
...Hollow part (4) (4B) (4b)
...Pile guide hole (5) ...Joint member
(6) (6aH6b)...Joint hole (7)...
...Water injection hole. (8)...Water surface (10)...Support layer (+2...Joint part (9)...Soft layer (11)...・Sand layer (1 ■... Lifting boat H...-- Vibro hammer, -

Claims (1)

[Claims] The completed marine structure is vertically divided into elements to form a floating structure, and furthermore, the elements are provided with pile guide holes vertically and vertically, and each divided part has a connection hole with the adjacent element. A joint is provided, and the element is transported to the seabed surface at the installation point, and then water is injected into the hollow part of the element to a state close to neutral buoyancy, allowing it to temporarily bottom on the seabed, and then further adjacent to the seabed. After the elements are temporarily brought to the bottom in the same way and the adjacent elements are temporarily joined together, a support pile is driven from the pile guide hole of each element, and if necessary, water is poured into the hollow part of each element. A method for constructing a foundation for an offshore structure, characterized by injecting a filler and joining joint parts by means such as grouting.