JP2007092454A - Hybrid artificial ground constructed in ocean space, and construction method for the hybrid artificial ground - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an artificial ground which allows highly precise control over installation location and requires a shorter construction period and less costs, and a construction method for the artificial ground. <P>SOLUTION: The hybrid artificial ground is a marine structure which is provided by reinforcing and constructing a pile structure driven into seabed ground, using caissons installed on the four corners of the pile structure. The hybrid artificial ground is also a marine structure which is provided by reinforcing and constructing pile structures attached to a temporary framework steel frame, using reinforced concrete wall panels and floor panels. The steel frame temporary framework is a rectangular parallelepipedic structure which is formed of four hollow steel pipes, which are set vertical and parallel with each other and are erected on the apexes of a square, respectively, and frame materials which are joined perpendicularly to the tops and bottoms of adjacent steel pipes, respectively. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a hybrid type ground constructed in an ocean space, and more particularly to an artificial ground combining a pile structure and a caisson structure and a construction method thereof.

  Conventionally, a plurality of construction methods have been proposed as means for constructing artificial ground in an ocean space.

  The first proposal is a method of constructing artificial ground in an ocean space using a pile structure. That is, the pile structure construction method is a construction method in which a pile is placed on the seabed and an offshore building is constructed based on the pile. Since it is possible to drive a pile at a predetermined point, it is possible to drive a pile at an accurate point according to the design drawing. Moreover, although an offshore structure is manufactured using several piles, the rigidity of the seabed geology of the seabed between each pile and the flatness of the seabed are not ask | required. In other words, whether or not piles can be placed is only a matter of placing piles, and it is possible to build offshore buildings even if some flatness between each pile and rigidity of the seabed geology are impaired. It is.

  The second proposal is a method of constructing artificial ground in an ocean space using a caisson structure. The caisson structure is a box-like structure having a size of about 15 m × 15 m, which is previously constructed on the land with concrete and steel. Inside the caisson structure is a hollow, transported in a floating state on the sea after providing a wall other than the upper surface on land, moved to the destination point in a floating state, and entered the seawater etc. into the interior at the installation point, The caisson structure's ascent and descent movements are controlled by the incoming weight, and it is submerged on the sea floor. Sealing materials are provided at both ends of the side wall plate.

  Furthermore, a landfill method exists as a third proposal. In other words, this is a simple conventional technique for replacing seawater and earth and sand while laminating a large amount of earth and sand on the seabed.

  A fourth proposal is the float method. It is a method of laying large floating objects on the sea, and there is an advantage that floating objects can be manufactured in a free shape on land and that laying is easy.

JP 2003-3453 A

  However, some problems have arisen in these conventional methods.

  In the first pile structure construction method, it is usually necessary to drive the pile to a depth that produces axial strength that can reach the hard rock and face the horizontal stress. For this reason, the driving time of the pile has increased. In addition, the work at sea has been a factor that further increases the construction time because the work cannot be performed if the sea conditions deteriorate.

  Moreover, in order to cope with the stress in the horizontal direction, it is necessary to increase the diameter of the pile, but this point is also a factor for extending the placing time.

  On the other hand, the second caisson structure method requires flatness of the bottom of the caisson. In other words, since the caisson structure is usually formed of a rectangular parallelepiped, the caisson structure may be inclined when the sea floor is not flat. Furthermore, the caisson structure is huge, and it is difficult to specify the installation position with high accuracy by controlling the position of the caisson structure in the sea where the base axis does not exist.

  Furthermore, the third landfill method has a problem that a large amount of earth and sand is required and the construction period is significantly longer than other methods and the cost is increased. Moreover, the phenomenon of ground subsidence and land liquefaction after landfill has not been solved.

  The float, which is the fourth method, cannot be used unless the wave height is 40 cm or less, and in order to use it normally, a breakwater is installed around the float in order to ensure the sea area to be used as a constant hydrostatic surface. On the other hand, the cost was added to the breakwater installation.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an artificial ground that has a high position control accuracy at the time of installation, has a short construction period, can cope with a wide range of required horizontal / vertical forces after completion, and a construction method thereof.

  In order to achieve the above-mentioned object, the hybrid artificial ground constructed in the marine space of the present invention is constructed in the marine space constituted by a structure having a pile structure to be placed on the seabed ground at the four corners. In addition, it is composed of caissons with pile structures placed on the seabed ground at the four corners. The pile structure may be configured such that a steel pipe is provided in advance and the pile is arranged at the center thereof.

  When there is a gap between the caisson and the seabed ground, the gap can be filled with fine sand, concrete milk, or mortar, so that it can be installed even on an uneven seabed.

  Furthermore, when the caisson is made of steel shell or concrete shell, an artificial ground suitable for cost and sea conditions can be provided.

  In addition, the caisson and the pile structure are joined in a stretchable manner, and a floor board is further provided on the upper part of the integrated structure, so that the sea level of the artificial ground after completion can be adjusted freely.

  By further having a liquid storage tank structure inside the caisson, the space on the artificial ground and the space inside the artificial ground can be effectively utilized.

  By having a living space structure inside the caisson, it becomes possible to build a cheaper living space at sea. The pile structure, the steel frame temporary frame, and the side wall plate may be integrated, and a floor plate may be further provided on the top.

  Moreover, the construction method of the hybrid system artificial ground which concerns on this invention constructs in the marine space comprised from the structure provided with the pile structure put on the seabed ground at the four corners of the side part.

  Furthermore, a caisson made of a rectangular parallelepiped having a width the same length as the specific interval is set between the pile structures after the pile structure is placed at a predetermined interval at two points on the predetermined submarine ground. A pile structure may be further laid and built in the marine space so that the opposite side surface is inserted by being sunk so as to be inserted into the ocean.

  Pile construction is driven in a short time in four directions in the case of a quadrilateral planar work table centered on a fixed work table by using a pile driving device capable of driving multiple piles at the same time. Can be set up.

A process of installing and stabilizing a predetermined steel temporary frame in an integrated form in the sea or in the sea;
The pile is driven along the steel temporary frame and the side wall iron or concrete plate is vertically built along the steel temporary frame and integrated with the steel temporary frame and the already installed pile. A process of stabilizing as a wallboard structure,
You may build in the marine space which arranges or fixes the iron and concrete floor board previously created on the said pile head by aligning the pile head exposed on the sea horizontally.

  According to the present invention, the pile structure and the caisson structure are constructed in an integrated manner, and the vertical and horizontal proof stresses of the entire structure can be freely adjusted in order to function in an integrated form.

  If the caisson upper surface is converted to a working floor and the structure of the pile driving support mechanism such as cantilever is combined with caisson insertion and subsidence appropriately, the effect of the surrounding sea conditions will be reduced, and the water depth will be able to be piled. For example, it is possible to respond appropriately to changes in pile shape / scale and wide changes in pile spacing. For this reason, an artificial ground consisting of a pile structure, a caisson structure, and a combination / hybrid structure thereof can be constructed in a short period of time centering on a work table on the sea surface, completely independent of the surrounding land. Moreover, the construction cost can be reduced by shortening the construction period.

  Embodiments of the present invention will be described below with reference to FIGS.

  FIG. 1 schematically illustrates the structure of a hybrid artificial ground constructed in an ocean space according to the present invention. FIG. 1A shows a schematic plan view, and FIG. 1B shows a cross-sectional view along AA.

  In FIG. 1A, reference numeral 2 denotes a caisson, and its shape is an octagon obtained by cutting off the corners of the four corners of the square at an angle of 45 degrees with respect to each side. It joins with the adjacent caisson 2 at the sides corresponding to the four sides of the square. A pile 4 is arranged at the center of each small square space formed at the cut off four corners, and the pile 4 is coupled to the caisson 2 via a coupling portion 6 that can be expanded and contracted. Each caisson 2 is connected to the adjacent caisson 2 that contacts the adjacent caisson at each side and is adjacent to the adjacent caisson 2 via the pile 4 and the diagonally located caisson 2. The caisson 2 is composed of a steel shell caisson using a plurality of H steels for the skeleton and using a steel plate or the like for the side plate. However, it is not limited to a steel shell caisson, and may be a reinforced concrete shell whose skeleton is composed of reinforcing bars. In any case, the caisson 2 is formed in an internal hollow box shape, and the upper surface is opened. The size of the caisson 2 is, for example, 15 meters deep, 15 meters wide, and 20 meters high in the case of an ocean having a water depth of 10 meters. Further, the pile 4 may be either a steel material or a concrete material.

  FIG. 1 (B) shows a cross-sectional view of the artificial ground of FIG. 1 (A) cut along line AA. The caisson 2 is set on the seabed 8. Here, 10 indicates the sea level. The caisson 2 is coupled to the pile 4 by a plurality of coupling portions 6. The pile 4 is driven to the seabed 8 to a depth of 1 to 2 meters.

  That is, regarding the horizontal stress, the frictional force between the caisson 2 and the seabed 8 and the horizontal stress are offset in the configuration of the present invention in which the caisson and the pile support the horizontal stress compared to the case where the horizontal stress is supported only by the pile 4. The For this reason, a large horizontal stress does not occur in the pile 4. On the other hand, in order to disperse the vertical force at the bottom of the caisson in the vertical direction, the pile 4 does not require axial strength, and the axial strength shared by the pile side and the tip of the pile required for the pile driving method is generated. Therefore, it is not necessary to drive piles deeply into the seabed, which was necessary for this purpose.

  On the other hand, in the vertical direction, the pile 4 and the caisson 2 are integrated as described above, and the buoyancy of the caisson 2 cancels out the vertical friction force and the reverse friction force acting on the pile 4. For this reason, the vertical strength and the horizontal strength of the artificial ground composed of the pile 4 and the caisson 2 are controlled. That is, the buoyancy of the entire artificial ground can be controlled by controlling the buoyancy of the caisson 2 by the amount of seawater injected into the caisson 2 and controlling the amount of seawater injected by the caisson 2 of the entire artificial ground.

  Then, the construction method of a hybrid type artificial ground is demonstrated concretely using FIGS.

  2 to 6, (A) shows a side view and (B) shows a plan view. As shown in FIG. 2 (A), a fixed work table 12 having a width of 50 meters and a depth of 50 meters is installed 1 meter above the sea surface at a depth of 10 meters in the coastal area, and the fixing work is performed as shown in FIG. 3 (A). A cantilever 16 is provided at the end of the base 12, the beam length is 15 meters, a pile driving machine 18 is provided at the tip, and the upright pile pillar 4 is driven. Here, the pile driving machine 18 may be either a vibration hammer or a weight hammer.

  As shown in FIG. 4, the caisson 2 manufactured in advance by a dry dog or the like is pulled by the towed ship 20 and is transported and fitted to three existing pile driving points, thereby enabling accurate subsidence.

  The caisson 2 transported as shown in FIG. 5 is laid down to the sea bottom with its three corners in contact between the piles. If the caisson is box-shaped and has a bottom plate, water is poured into the caisson and set. Here, since caisson laying positioning is performed at the pile position, it is easier than positioning the caisson alone in the conventional method, and laying can be performed in a short time.

  Further, as shown in FIG. 6, the upper part of the caisson 2 that has settled and stabilized is shielded by a floor board 22 made of concrete or steel plate, and a pile is placed on one corner side portion where the caisson remains. Then, a cantilever 16 similar to that shown in FIG. 3 is provided on the pile facing the open ocean, and an upright pile column is driven from the cantilever 16 to the open ocean by 15 meters using the pile driver 18 provided. Subsequently, returning to the process of FIG. 4 again, the caisson is sunk so as to fit between the three piles that have already been placed. After that, the upper part of the caisson is shielded with concrete, and a pile is further driven in the remaining one corner side of the caisson that has been laid. By repeating this process across the fixed work table 12 in both the vertical and horizontal directions, piles are driven every 15 meters, and the caisson is sunk between them, and the artificial ground with a more stable structure can be of any size. Installed. By starting from the original fixed worktable and repeating the above work in sequence, the caisson itself becomes a worktable in turn, resulting in a stable structure, and the construction can be promoted without being affected by sea conditions, so the process is based on complex sea conditions To eliminate the delay.

  In addition, two or more pile driving machines 18 are connected in series, and the caisson is fitted using the piles that have already been placed in the correct position. After the caisson is placed in the correct position, the upper surface of the caisson is used as the work floor. It is also possible to improve the efficiency of pile driving by providing a carriage that moves over the cantilever. The construction period can be shortened by increasing the configuration and the number of pile driving machines 18 and combining the pile driving work and caisson fitting / sinking work.

  Furthermore, as shown in FIG. 7, when the sea bottom is not flat, a pile is driven and the caisson is sunk until the most projecting point 24 on the sea bottom contacts the bottom of the caisson. After that, it is possible to maintain flatness by pouring fine sand, concrete milk or mortar into the sea bottom from the hole 26 provided in the caisson bottom in advance to fill the gap between the caisson bottom and the sea bottom.

  Further, a hybrid type artificial ground not using a caisson and a construction method thereof will be described in Example 2 with reference to FIGS. In the case of offshore structure construction using piles placed on the seabed ground, as shown in FIG. 8A, a predetermined steel frame temporary frame 40 formed into a cube is installed and stabilized in advance in an integrated form on the sea and in the sea. . This temporary steel frame 40 is vertical and parallel to each other, and is a frame that is vertically coupled to four hollow steel pipes 42 standing at the apexes of a square and the top and bottom of adjacent steel pipes 42, respectively. The material 44 forms a rectangular parallelepiped. That is, the steel pipe 42 is arranged in a columnar shape, and the frame material 44 is arranged in a beam shape. Moreover, the grooved steel 46 is joined in parallel so that the adjacent steel pipes 42 face each other. When this temporary steel frame 40 is installed and stabilized in an integrated form on the sea and in the sea, the steel pipe 42 is installed so as to stand vertically on the bottom of the sea.

  A pile structure 48 is driven into the bottom of the sea along the temporary framework 40 (FIG. 8B). The pile structure 48 is erected so as to penetrate the center of the hollow steel pipe 42 and be pressed from above so that the tip of the pile structure 48 is embedded in the sea bottom. By adopting this method, it is not necessary to position the pile structure 48 at the time of embedding, and the embedding can be performed without being affected by waves. FIG. 8B shows a state before three pile structures 48 are buried and one is inserted. FIG. 8C shows a state where the entire pile structure 48 is embedded.

  Further, if necessary, a groove steel 46 is provided on the side surface of the steel pipe 42 of the temporary steel frame 40, and the side wall iron / concrete wall plate structure 50 is vertically inserted along the groove steel 46. It is integrated with the steel frame temporary frame / placed pile and stabilized as an underwater pile structure 48 and an iron / concrete wall plate structure 50 (FIG. 8D). FIG. 8D shows a state at the time of insertion, and FIG. 8E shows a state after the insertion. FIG. 9 shows a detailed drawing about the arrangement of the iron / concrete wall plate structure 50 and the grooved steel 46. In FIG. 9, the channel steel 46 is joined to the outside of the web with respect to the steel pipe 42 penetrating the pile structure 48, and the end of the iron / concrete wall plate structure 50 is joined to the inside of the web. The grooved steel 46 provided on the side surface of the steel pipe 42 is omitted depending on the overall structural strength of the steel temporary frame 40, and the frame material 44 can be directly attached to the steel pipe from both sides (FIG. 12). The omission of the grooved steel 46 reduces the overall weight of the temporary steel frame and provides favorable results. Further, the groove steel 46 is similarly joined to the outside of the web in the direction rotated 90 degrees from the iron / concrete wall board structure 50, and the end of the iron / concrete wall board structure 50 is joined to the inside of the web. To do.

  Subsequently, the head of the pile structure 48 is cut and aligned horizontally (FIG. 8F).

  An iron / concrete floor board 52 prepared in advance is horizontally installed and fixed on the pile head (FIG. 8G). In addition, it can be installed over a wider area by providing another steel frame temporary frame 40 adjacent to the steel frame temporary frame 40 (FIG. 10). Further, FIG. 11 shows a configuration diagram in which the frame material 44 is not limited to columns and beams but the brace material 54 is incorporated.

  A third embodiment of the hybrid artificial ground according to the present invention will be described with reference to FIGS. The major difference from FIG. 11 is that the frame members 44 and 56 are doubled, and are composed of a frame member 44 provided inside the steel pipe 42 and 56 provided outside the steel pipe 42. If the frame members 44 and 56 are made of L-shaped steel, an inexpensive and strong structure can be obtained. By combining with the brace material 54 in addition to the double frame material, it is possible to construct a strong hybrid type artificial ground framework.

  A fourth embodiment of the hybrid artificial ground according to the present invention will be described with reference to FIG. A grooved steel 46 is joined to the outside of the web, and a rubber seal is provided at the end of the iron / concrete wallboard structure 50 inside the web. With this sealing material, a water stop effect can be obtained. Further, when the iron / concrete wall plate structure 50 is suspended inside the web, the grooved steel 46 and the iron / concrete wall plate structure 50 are not in direct contact with each other, and therefore can be inserted smoothly. It is also possible to omit the grooved steel 46 and add L-shaped steels 44 and 56 to both sides of the steel pipe 42.

  As described above, the marine work space is obtained by fixing the iron / concrete floor board, which is the marine work floor, to the marine space. A steel temporary frame with piles and concrete wall plates that support the work floor on the sea can be obtained in a stable shape between the sea hollows.

  By adopting this method, when caisson is used, it can be adopted even when the sea conditions in the nearby sea area are severe due to many difficulties in assembling and towing the caisson on land.

  In order to overcome this disadvantageous condition, a temporary steel frame is prepared on the work floor in advance, and this temporary frame is suspended from the sea using a crane on the work floor so that the tip of the temporary frame leg reaches the bottom of the sea. Include. When a pile is driven along the temporary framework, the position of the pile is already clearly defined, the driving operation is easy and reliable, and there is a merit of the present idea in that it is completed in a short time.

  In addition, the reinforced concrete wall can be built easily because the tip of the temporary frame assembly leg is already stable on the sea bottom, and it can be completed in a short time.

  This method can emphasize the merit of the caisson towing work as a method with little change in work efficiency, while the work efficiency depends on the surrounding sea conditions.

  In addition, in the present embodiment, the steel temporary frame 40 having a uniform length of the steel pipe 42 has been described. However, the steel temporary frame framework in which the topography of the seabed is measured in advance and the four steel pipes are adapted to the topography to have different lengths. It is within the scope of design changes.

  Since the hybrid type artificial ground of the present invention can be created in the sea and on the sea, it can be easily installed even in places where conventional landfilling has been difficult, and oil field development, airport construction, fishing reef development, etc. are possible. .

BRIEF DESCRIPTION OF THE DRAWINGS The structure of the hybrid type artificial ground built in the ocean space which concerns on this invention is demonstrated roughly, (A) shows a schematic plan view, (B) shows AA sectional drawing. It is a construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention, Comprising: (A) Side view and (B) Top view after pile driving | running | working are shown. It is a construction method of the hybrid type artificial ground built in the ocean space which concerns on this invention, Comprising: The (A) side view and (B) top view of a pile driving device are shown. It is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention, Comprising: (A) Side view and (B) Top view at the time of caisson conveyance are shown. It is a construction method of the hybrid type artificial ground built in the marine space which concerns on this invention, Comprising: (A) Side view and (B) Top view at the time of caisson installation are shown. It is a construction method of the hybrid type artificial ground built in the marine space which concerns on this invention, Comprising: The (A) side view and (B) top view of the further pile placing process are shown. The side view in case it is a construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention, and the sea bottom is not flat is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The process figure which is the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The detailed drawing of the steel pipe vicinity of the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The block diagram which has arrange | positioned the several steel frame temporary frame in the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The block diagram which applied the bracing structure to the frame material in the construction method of the hybrid system artificial ground built in the ocean space which concerns on this invention is shown. The block diagram by the 3rd Example is shown in the construction method of the hybrid type artificial ground built in the ocean space which concerns on this invention. The block diagram by the 4th Example is shown in the construction method of the hybrid type artificial ground built in the ocean space which concerns on this invention.

Explanation of symbols

2 Caisson 4 Pile 6 Coupling part 8 Sea bottom 10 Sea surface 12 Fixed work table 14 Positioning device 16 Cantilever 18 Pile driver 20 Towing ship 22 Floor plate 24 Sea bottom most protruding point 26 Filling material injection hole 40 Steel temporary frame 42 Steel pipe 44 Frame material 46 Channel steel 48 Pile structure 50 Iron / concrete wall board structure 52 Iron / concrete floor board 54 Brace material

Claims (14)

  A hybrid artificial ground constructed in a marine space composed of structures with pile structures placed on the seabed ground at the four corners.   2. The hybrid artificial ground according to claim 1, wherein the pile structure is configured such that a steel pipe is provided in advance and a pile is arranged in the center thereof.   The hybrid artificial ground according to claim 1, wherein a pile structure to be placed on the seabed ground is constructed in an ocean space composed of caissons provided at the four corners of the side.   2. The hybrid artificial ground constructed in an ocean space according to claim 1, wherein the gap is filled with fine sand, concrete milk or mortar when there is a gap between the caisson and the seabed ground.   2. The hybrid artificial ground constructed in an ocean space according to claim 1, wherein the caisson is made of steel shell or concrete shell.   2. The hybrid artificial ground constructed in an ocean space according to claim 1, wherein the caisson and the pile structure are joined in a stretchable manner, and a floor board is further provided on the integrated structure.   The hybrid artificial ground constructed in an ocean space according to claim 1, further comprising a tank structure for buoyancy adjustment inside the caisson.   The hybrid artificial ground constructed in an ocean space according to claim 1, further comprising a living space structure inside the caisson.   The hybrid artificial ground according to claim 1, wherein the pile structure, the steel frame temporary frame and the side wall plate are integrated and a floor plate is further provided on the upper portion.   The hybrid artificial ground according to claim 1, wherein sealing material is provided at both ends of the side wall plate.   A hybrid artificial ground construction method in which a pile structure to be placed on the seabed ground is constructed in a marine space composed of structures with four corners on the sides.   A caisson made of a rectangular parallelepiped having the same length as the specific interval is placed between the pile structures after placing the pile structure with a specific interval at two points on the predetermined seabed ground. 12. The hybrid artificial ground construction according to claim 11, wherein the position is set so as to be laid, and then the caisson upper surface is covered with a shielding plate so as to be used as a work floor, and a pile structure is further constructed in the ocean space. Method.   The construction method for a hybrid artificial ground according to claim 11, wherein the pile structure is constructed in an ocean space, wherein the pile structure is constructed by a pile driving device capable of simultaneously placing a plurality of piles. A process of installing and stabilizing a predetermined steel temporary frame in an integrated form in the sea or in the sea;
The pile is driven into the center of the steel pipe provided in the steel temporary frame and the steel or concrete plate for the side wall is vertically built along with the steel temporary frame to be integrated with the steel temporary frame and the installed pile. The process of stabilizing the structure and the iron / concrete wallboard structure,
The construction method of a hybrid type artificial ground according to claim 10, wherein the pile heads exposed on the sea are horizontally aligned and constructed in an ocean space in which iron and concrete floor boards prepared in advance are horizontally installed or fixed.

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