JP2008038524A - Earthquake-resistant reinforcing structure of quay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an earthquake-resistant reinforcing structure of a quay which is excellent in economical efficiency without changing a normal. <P>SOLUTION: The earthquake-resistant reinforcing structure 1 of the quay is constituted by driving a plurality of piles 3 in rows so that they are positioned reverse to the existing quay 2, and by forming a load-transmission plate 4 made of underwater concrete in the sea-bottom area which is sandwitched between the quay 2 and the pile 3. Then a horizontal force at the time of an earthquake, which acts on the ground expanded on the quay 2 and at the rear of it, is transmitted to the point close to the top of the pile 3 through the medium of the load-transmission plate 4, and the horizontal force at the time of an earthquake is supported by bending stiffness of the pile 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a seismic reinforcement structure for a quay that is applied when a seismic reinforcement is applied to an old quay or a quay constructed based on an old design standard.

  In order to prevent bank breakage due to river flooding and quay breakage due to waves, the bank has been traditionally protected against dams and quay walls. Collapse often causes great damage. Moreover, even if the revetment is not aging, it needs to be reconstructed if it is built with old design standards. In particular, for seawalls that do not meet the current seismic standards, seismic reinforcement work is urgently required to prevent collapse due to earthquakes.

  Here, in order to seismically reinforce the revetment, conventionally, a method has been adopted in which the front of the existing quay is covered to make an inclined revetment, or the normal of the existing quay is put forward to construct a new structure. It was.

JP-A-9-279540

  However, in the case of a slope revetment, the closer to the quay, the shallower it becomes, so there is a problem that ships that can be anchored on the quay are restricted due to drafts.

  In addition, when constructing a structure in front of an existing quay, it is necessary to increase the scale of the structure or improve the sea floor near the quay to ensure passive resistance. There was a problem that it was very expensive.

  On the other hand, there is also proposed a method of seismic reinforcement of the existing quay without changing the normal, but it is necessary to improve the ground on the back side of the quay or to reinforce the existing caisson constituting the quay, After all, there was a problem that a large amount of cost was required for the seismic reinforcement work on the quay.

  The present invention has been made in consideration of the above-described circumstances, and an object thereof is to provide a quay quake-proof reinforcement structure excellent in economic efficiency without changing the normal line.

  In order to achieve the above-mentioned object, the quake-proof seismic reinforcement structure according to the present invention is driven in a row so as to face the quay wall at a predetermined distance from the existing quay wall as described in claim 1. A plurality of piles and a load transmission plate formed by placing underwater concrete in a water bottom region sandwiched between the quay and the piles, wherein the piles are The shafts are set so as to be parallel to the quay and so that their head positions are below the water surface and above the top edge of the load transmission plate.

  Moreover, the seismic reinforcement structure of a quay according to the present invention is such that the cross-sectional shape of the pile is an I shape or an H shape.

  The seismic reinforcement structure for a quay according to the present invention is configured by connecting the webs of two pile members having a T-shaped cross section to constitute the pile.

  The seismic reinforcement structure for a quay according to the present invention sets the head position of the pile to a position that is a predetermined height higher than the water bottom ground, and the head position of the pile in the height relationship is the load transmission plate. It is made to coincide with the top of the.

  Moreover, the seismic reinforcement structure for a quay according to the present invention is a space provided with a water-permeable hole in a web located near the head of the pile, and surrounded by a web and a flange in the vicinity of the head of the pile after driving the pile. A vegetation base made of gravel, crushed stone, etc. will be laid.

  In the seismic reinforcement structure for a quay according to the present invention, first, a plurality of piles are driven in a row so as to be opposed to the quay at a position separated from the existing quay by a predetermined distance.

  Next, underwater concrete is placed in the bottom area sandwiched between the quay and piles to make a load transmission plate.

  Here, when driving the pile, the pile's strong axis is parallel to the quay and its head position is below the water surface and above the top edge of the load transmission plate.

  In this way, the horizontal force at the time of earthquake acting on the quay or the ground spreading on the back of the quay is transmitted to the pile via the load transmission plate, and the horizontal force at the time of earthquake transmitted to the pile depends on the bending rigidity of the pile. Thus, the existing quay can be seismically reinforced with piles and load transmission plates.

  In addition, in such seismic reinforcement, ground improvement work and construction of heavy structures can be omitted, so construction costs can be reduced and the quay itself need not be modified. It becomes possible to put it into service.

  In addition, since the pile is driven so that the head position of the pile is below the water surface and above the top of the load transmission plate, it is possible to drive the pile according to the draft of the ship, and hinder the entry of the ship. Absent.

  As long as the pile can support the horizontal force at the time of earthquake acting from the quay with bending rigidity, the cross-sectional shape is arbitrary and may be, for example, a rectangular tube shape or a cylindrical shape, but the cross-sectional shape of the pile is I shape or H shape Then, since the center of gravity is located on the web, it is possible to suspend the web with the web as a suspension point, and press-fitting using a vibro hammer or the like is facilitated.

  Here, if the pile having the above-described I-shaped or H-shaped cross-section is configured by connecting two pile member webs having a T-shaped cross section, even a large pile can be handled easily. Become. In such a configuration, one of the two pile members having a T-shaped cross section is driven first into the water bottom ground, and then the connection portion of the other pile member is engaged with the connection portion of the pile member that has been driven in advance. What is necessary is just to drive in this other pile member, making it match.

  The connecting portion does not need to be locked in the vertical direction, and it is sufficient that the connecting portion is locked in the horizontal direction so that the bending rigidity is exhibited as a whole when a horizontal force is applied to the pile head.

  Further, if the head position of the pile is set to a position that is a predetermined height higher than the water bottom ground, and the head position of the pile is matched with the top end of the load transmission plate in the height relationship, Or since the horizontal force at the time of earthquake which acts on the ground spreading behind it can be supported at a higher position, it becomes possible to more strongly seismically strengthen the revetment structure of the previous quay.

  In addition, if a web located near the head of the pile is provided with a water permeable hole and a vegetation base made of gravel, crushed stone, etc. is laid in the space surrounded by the web and flange near the head of the pile, In addition, aquatic plants grow on the vegetation base and aquatic animals also propagate along with it, thus providing an earthquake-resistant reinforcement structure that is environmentally friendly.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a seismic reinforcement structure for a quay according to the present invention will be described with reference to the accompanying drawings. Note that components that are substantially the same as those of the prior art are assigned the same reference numerals, and descriptions thereof are omitted.

  FIG. 1 is a diagram showing a seismic reinforcement structure for a quay wall according to the present embodiment. As can be seen from these drawings, the seismic reinforcement structure 1 for a quay according to this embodiment is driven by a plurality of piles 3 in a row so as to face the existing quay 2 and sandwiched between the quay 2 and the pile 3. The load transmission plate 4 made of underwater concrete is formed in the bottom area, and the horizontal force at the time of earthquake acting on the quay 2 and the ground spreading behind it is transmitted to the vicinity of the top of the pile 3 through the load transmission plate 4. Such an earthquake horizontal force is configured to be supported by the bending rigidity of the pile 3.

  The quay wall 2 is configured by forming an apron 6 so that the steel pipe sheet pile 5 is driven into a column shape to support the back earth pressure, and the top of the steel pipe sheet pile becomes an edge.

  The pile 3 is manufactured as a factory as an RC precast pile having an I-shaped cross-sectional shape, and is driven into the water bottom ground at a position separated from the existing quay wall 2 by a horizontal distance W. The horizontal distance W is the distance above which the workability when driving the pile 3 is not deteriorated and does not adversely affect the existing quay 2 is described above due to the lower limit value, the out-of-plane deformation of the load transmission plate 4 and the like. What is necessary is just to set suitably the distance by which the horizontal force at the time of an earthquake is not transmitted to the pile 3 as an upper limit.

  Here, the plurality of piles 3 are driven in a row so that their strong axes (y-axis shown in FIG. 1 (b)) are parallel to the edge of the quay wall 2, in other words, the edge of the apron 6. It is. What is necessary is just to determine suitably the magnitude | size of the cross section of the pile 3, a driving depth, or driving pitch according to the property of the horizontal force at the time of an earthquake mentioned above.

  Further, it is desirable that the piles 3 have their head positions coincide with the top end of the load transmission plate 4 so that the ship using the quay 2 can not be restricted by draft.

  On the other hand, the load transmission plate 4 has a width, that is, a horizontal distance W or a thickness T between the quay 2 and the pile 3 so that the horizontal force during an earthquake acting on the quay 2 and the ground spreading behind the quay 2 can be transmitted to the head of the pile 3. Or concrete strength etc. are set up suitably.

  In order to construct the quay-side seismic reinforcement structure 1 according to the present embodiment, as shown in FIG. 2, first, a plurality of piles 3 are located at a predetermined distance W from the existing quay 2 and face the quay. Drive in a row.

  In order to drive the pile 3 into the water bottom ground at the above-described position, the vibratory hammer 13 is suspended from the crane 12 installed on the work table ship 11, and the pile 3 is removed from the bottom of the water while holding the web center of the pile 3 with the vibratory hammer. Vibration press fit into the ground.

  Here, when driving the pile 3, as described above, the strong axis thereof is parallel to the quay 2 and the head position coincides with the top end of the load transmission plate 4 to be constructed in a later process. To do.

  Next, underwater concrete is placed in a water bottom region sandwiched between the quay 2 and the pile 3 to form a load transmission plate 4.

  It is efficient to place the underwater concrete sequentially from the place where the pile 3 has been driven while watching the progress of the pile 3 driving operation. In placing the underwater concrete, the pile 3 is buried in the seabed ground with the dam plate 21 applied to the flank side flange surface, and then the underwater concrete is placed using the dam plate as a formwork.

  As described above, according to the seismic reinforcement structure 1 for a quay according to the present embodiment, an earthquake horizontal force acting on the quay 2 or the ground spreading on the back thereof is transmitted to the pile 3 via the load transmission plate 4. At the same time, the earthquake horizontal force transmitted to the pile 3 is supported by the bending rigidity of the pile.

  Therefore, the existing quay wall 2 can be seismically reinforced by the pile 3 and the load transmission plate 4. In addition, in such seismic reinforcement, ground improvement work and construction of heavy structures can be omitted, so construction costs can be reduced and there is no need to modify the quay 2 itself. Even inside, the quay 2 can be used continuously.

  Moreover, according to the seismic reinforcement structure 1 for a quay according to the present embodiment, since the pile 3 is driven so that the head position of the pile 3 coincides with the top end of the load transmission plate 4, the driving depth of the pile 3 is necessary. There will be a minimum and there will be fewer concerns that the draft will be restricted by draft.

  Moreover, according to the seismic reinforcement structure 1 of the quay according to the present embodiment, since the cross-sectional shape of the pile 3 is I-shaped, vibration press-fitting with a vibro hammer using the web as a suspension point is possible, and the pile 3 is driven. Becomes easier.

  In the present embodiment, the head position of the pile 3 is made to coincide with the top end of the load transmission plate 4 so that the ship using the quay 2 can only be restricted by draft, but the quay 2 is used. When the draft of the ship is relatively small, it is not necessary to drive the pile 3 to such a depth, and it may be appropriately determined within the range below the water surface and above the top end of the load transmission plate 4 according to the draft of the ship.

  According to such a configuration, it is possible to reasonably shorten the construction period of pile driving.

  Moreover, in this embodiment, as shown in FIG.1 and FIG.2, the head position of the pile 3 was made to correspond to the seabed ground, and by this structure, the use restriction of the ship by draft was excluded as much as possible. When the size of the ship used is small, as shown in FIG. 3, the head position of the pile 3 is set to a position that is a predetermined height h higher than the seabed ground, and the load position of the head position of the pile 3 is transmitted in relation to the height. It may be made to coincide with the top end of the plate 4.

  According to this configuration, since the horizontal force during an earthquake acting on the quay 2 or the ground spreading behind it can be supported at a higher position, the revetment structure of the conventional quay 2, that is, the steel pipe sheet pile 5, can be strengthened. Seismic reinforcement is possible.

  In the present embodiment, a vibro hammer is used for driving the pile 3, but a hydraulic hammer, for example, may be used instead.

  Further, in this embodiment, the pile 3 is configured by an RC precast-integrated pile having an I-shaped cross section. However, when the cross-sectional size is large and driving efficiency is lowered, as shown in FIG. You may employ | adopt the pile 41 formed by connecting the webs of the two pile members 42a and 42b which have.

  In such a modified example, of the two pile members 42a, 42b having a T-shaped cross section, for example, the pile member 42a is driven in advance into the seabed ground, and then the other portion is connected to the connecting portion 43a of the pile member 42a that has been driven in advance. What is necessary is just to drive in this other pile member 42b, engaging the connection part 43b of the pile member 42b.

  The connecting portions 43a and 43b do not need to be locked in the vertical direction, and need only be locked in the horizontal direction so that the pile 41 exhibits bending rigidity as a whole when a horizontal force acts on the pile head.

  According to the configuration of such a modified example, even a large pile can be handled easily. In addition, what is necessary is just to make it blow away sand by spraying a water flow to engagement space, when driving | striking of a pile becomes difficult when sand enters into the engagement space of connection part 43a, 43b.

  Although not mentioned in the present embodiment, as shown in FIG. 5, instead of the pile 3, a pile 51 in which a water permeable hole 52 is formed in a web near the pile head is employed, and the pile 51 is driven. Thereafter, a vegetation base 53 made of gravel, crushed stone, or the like may be laid in a space surrounded by the web and flange in the vicinity of the head of the pile 51.

  According to such a configuration, the aquatic plant grows on the vegetation base 53 and the aquatic animals also propagate along with it, thus providing an earthquake-resistant reinforcement structure considering the environment.

It is a figure of the quay-seismic reinforcement structure 1 which concerns on this embodiment, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows an AA line. It is the figure which showed a mode that the seismic reinforcement structure of the quay which concerns on this embodiment was constructed | assembled, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows a BB line. The figure which showed the seismic reinforcement structure of the quay which concerns on a modification. It is the figure which showed the pile 41 which concerns on a modification, (a) is horizontal sectional drawing, (b) is detailed sectional drawing of a connection location. It is a figure of the seismic reinforcement structure of the quay which concerns on a modification, (a) is a vertical sectional view, (b) is a horizontal sectional view which follows a CC line.

Explanation of symbols

1 Seismic reinforcement structure of quay 2 Quay 3, 41, 51 Pile 4 Load transmission plate 52 Permeation hole 53 Vegetation base

Claims (5)

A plurality of piles driven in a row so as to face the quay at a predetermined distance from an existing quay, and underwater concrete is placed in a bottom area sandwiched between the quay and the pile. An anti-seismic reinforcement structure comprising a formed load transmission plate, wherein the plurality of piles are such that their strong axes are parallel to the quay and their head positions are below the water surface and the load transmission Seismic reinforcement structure for quay, which is set to be higher than the top of the plate. The seismic reinforcement structure for a quay according to claim 1, wherein a cross-sectional shape of the pile is an I shape or an H shape. The seismic reinforcement structure for a quay according to claim 2, wherein the piles are configured by connecting webs of two pile members having a T-shaped cross section. 2. The quay according to claim 1, wherein the head position of the pile is set to a position higher by a predetermined height than the water bottom ground, and the head position of the pile is made to coincide with the top end of the load transmission plate in the height relationship. Seismic reinforcement structure. Claims in which a water-permeable hole is provided in the web located near the head of the pile, and a vegetation base made of gravel, crushed stone, etc. is laid in the space surrounded by the web and the flange near the head of the pile after the pile is driven. Item 2. Seismic reinforcement structure for quay according to item 2.

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