JP2007321486A - Armed pipe aseismatic structure and armed pipe aseismatic reinforcing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an armed pipe aseismatic structure and an armed pipe aseismatic reinforcing method, easily coping with an unexpected earthquake, reducing weight in a reinforcing material, inexpensively and easily constructible in a short period, performing a delicate adjustment corresponding to a degree of a load, and easily changing reinforcement after construction. <P>SOLUTION: This armed pipe aseismatic structure has a plurality of armed pipes 2 filling a filler 3 inside for improving compressive strength and performing aseismatic reinforcement by contacting with a side surface of a structure 1, and connecting belts 4a, 4b and 4c for bringing the plurality of armed pipes 2 into pressure contact with a side surface of the structure 1 for integrating the movement in an earthquake of the plurality of armed pipes 2 and the structure 1. The armed pipe aseismatic structure is mainly characterized by fastening connecting belts 4a, 4b and 4c to the structure 1 by fastening force, a fastening position and a fastening width corresponding to the size of stress acting in the earthquake. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  In the present invention, a plurality of crust pipes are arranged around a structure for seismic reinforcement, connected by a connecting body, and the seismic load acting on the structure is distributed among a plurality of crust pipes, so that The present invention relates to a shell-pipe seismic structure and a shell-pipe seismic reinforcement method for improving the performance.

  In recent years, huge earthquakes have frequently occurred in various places. The memory of the Great Hanshin Awaji Earthquake is also new, but recently the Chuetsu Earthquake, the Fukuoka West Offshore Earthquake, etc. occurred, destroyed highways and railroad piers, collapsed buildings, and built L-shaped retaining walls along the road. It collapsed and caused great damage in various places.

  The damage to the piers reported in these earthquakes was the most due to brittle fracture due to insufficient shear force at the bottom of the column when the horizontal force of the earthquake was applied. Following this damage, destruction occurred in the order of about 1/3 of the height in the longitudinal direction from the center of the column or the bottom of the column, and further to the top of the column. In the case of structures with a ramen structure, in many cases, the central part is destroyed, and it has been reported that the beam was destroyed at the central part and the end part of the beam. PC (prestressed concrete) girders are broken at the center, like a ramen structure with a gap between the left and right sides, and brittle fracture occurs when the girders move from side to side. As for the L-type retaining wall, many report that the boundary between the vertical wall and the support part has been destroyed, and that the vertical stacked block-type retaining wall, represented by the tail arme type, has collapsed due to abdominal swelling. Has been.

  These lessons learned from earthquake damage are expected to be used in the design of new structures in the future. However, if a building that has already been constructed or is under construction does not have sufficient seismic strength, it will be a major earthquake in the future. There is a possibility of collapse when hit by. Then, what kind of reinforcement should be performed with respect to the existing building becomes a problem.

  Currently, there are three methods for seismic retrofit. The first is seismic reinforcement, the second is seismic reinforcement, and the third is seismic isolation. The first seismic reinforcement is intended to increase the earthquake resistance of the building or to improve toughness (deformation performance). Of these, the former corresponds to the installation of seismic walls and braces, and the latter corresponds to the reinforcement of columns and beams. The second type of seismic retrofit is to reduce damage to buildings by installing seismic dampers in high-rise buildings to absorb seismic energy. The third seismic isolation reinforcement is intended to reduce damage to buildings by providing seismic isolation structures under the foundation and intermediate floors to greatly reduce the seismic force transmitted from the ground.

  Now, as this seismic isolation structure, what was conventionally comprised from the pipe is proposed (refer patent document 1). The seismic isolation structure consists of a plurality of elongated, relatively flexible and concrete-filled pipes that are connected to the structure and extend towards the underlying foundation, at least some of which are structural It connects with the foundation so that things do not fall. The main load bearing column is placed on the foundation to receive the pipe row and a bearing device is inserted between the upper end of the column and the structure to allow lateral movement between them. Further, by absorbing the lateral rigidity from the load bearing force of the support column, the ground acceleration force is prevented from being transferred to the protective structure. With this configuration, buildings and other structures can be protected during an earthquake.

  However, the seismic isolation structure of Patent Document 1 requires foundation work, and is unacceptable for reinforcing existing buildings with a short construction period and low cost. In addition, most conventional seismic retrofits reinforce high-rise buildings, and it cannot be said that reinforcement is always possible regardless of the type of building. For example, it is structurally difficult to reinforce retaining walls or beams with seismic reinforcement. Moreover, as with the seismic isolation structure, it is difficult to reinforce with a short construction period and low cost.

  Seismic reinforcement is effective against these difficulties, and the following seismic reinforcement methods have been proposed (see Patent Document 2). That is, the seismic reinforcement method of Patent Document 2 is a method of sticking a reinforcing fiber sheet impregnated with a resin to the peripheral surface of a concrete columnar body to reinforce the pillar, and a plurality of reinforcing fiber sheets to be attached. A shell sheet having a plate-like portion obtained by impregnating and hardening a resin in the middle portion and a remaining non-impregnated portion and a remaining unimpregnated portion is formed, and a spacer is provided on the peripheral surface of the column. And then impregnating each unimpregnated portion with resin and sticking them to the peripheral surface of the column, and in the gap between the plate-like portion formed by this spacer and the peripheral surface, resin mortar etc. Filler is injected.

  With this configuration, the reinforcing work of winding the reinforcing fiber sheets around the concrete columnar body in multiple layers can be completed in a short time in a narrow place. In addition, a reinforcing material suitable for this method can be provided. However, the seismic reinforcement method of Patent Document 2 is originally a method of finishing such as painting or fireproof coating, and it is wrapped around the column bending due to the horizontal force of the earthquake or the enormous tension / compression force of the direct type. The strength of the resin between the reinforcing fiber sheets is weak, the resin impregnation between the reinforcing sheets is insufficient, the reinforcing sheets may be torn apart by external force, and originally the reinforcing fiber sheet is a unidirectional tensile The force exerts proof strength, but the compressive force does not have a reinforcing action, and cannot be said to be a sufficient reinforcing method.

  In addition, in order to prevent the collapse of the bridge pier from the destructive force of the earthquake, a steel plate was attached to the outside of the concrete leg and cement was filled between the leg and the steel plate, or the steel plate was wound with epoxy resin to bond the concrete and the steel plate The construction method (steel plate bonding method) is performed. This steel sheet winding method has a large reinforcing effect because there is little variation in the material characteristic values of the steel sheet and the elastic modulus is large. In addition, since epoxy resin has the property that it does not cure and shrink, it is excellent in fluidity, adhesiveness, high strength, and durability, and can sufficiently bond the pier and the steel plate. Since stress can be transmitted, the strength of existing piers can be improved.

JP-A-6-81514 JP 11-343744 A

  The seismic isolation structure described in Patent Document 1 described above copes with an earthquake by absorbing the horizontal force of the earthquake by first causing plastic deformation of the filler inside the pipe when an earthquake acts. And this seismic isolation structure supports the building in series as the foundation, and it is necessary to install it in the foundation part at the stage of building the building, and to reinforce the existing building with short construction period and low cost. It was difficult to do. In addition, because it is a seismic isolation structure installed in the foundation part, it is highly likely that the filling will be unusable after a single earthquake, and repair will be costly and will absorb seismic forces repeatedly. However, there is a need to install a damper for seismic control.

  Moreover, although the earthquake-proof reinforcement method of patent document 2 can complete reinforcement work in a short place in a short time and it becomes possible to reinforce at low cost, finishing such as painting and fireproof coating is necessary, and an unexpected force is required. It could not cope with the destructive power of the earthquake that occurred. The reinforcing fiber sheet exhibits a proof strength against a unidirectional tensile force, but does not exert a reinforcing action on a compressive force. In addition, the resin impregnation between the reinforcing fiber sheets has been confirmed empirically, and there are cases where a special sheet with a transparent portion formed is necessary in order to facilitate confirmation of resin impregnation because of large individual differences. In addition, the reinforcing fiber sheet is damaged due to ultraviolet rays, fire, vehicle collisions, and the like, and when the fiber is cut, the predetermined strength cannot be exerted, and thus there is a problem that it must be protected with mortar or the like.

  In the case of a direct type earthquake, the reinforcing methods such as Patent Documents 1 and 2 cause the earthquake force to directly act on the concrete pillars, and they are destroyed at once. Furthermore, the horizontal seismic force is applied to the building as a torsion, bending moment, and shearing force due to the characteristics of the structure, but the reinforcement method of Patent Document 2 is not sufficient for these. In this respect, the steel sheet winding method has high strength and excellent durability, and the building and the steel plate can be integrated to transmit stress, so that the strength of existing buildings against earthquakes can be greatly improved. it can. However, the steel plates used are heavy and difficult to construct by human power alone, and the amount of steel plates is enormous, making it difficult to reinforce at a simple, short construction period and low cost. Since the weight increases, it is impossible to apply an excessive load to the main body due to the weight for reinforcement. Due to its nature, it is difficult to use it in a retaining wall, a brick masonry structure, or a masonry structure.

  In addition, buildings have environmental changes and deterioration over time, and further reinforcement may be required due to changes in seismic standards and design methods according to laws and regulations. However, the seismic isolation structures disclosed in Patent Documents 1 and 2 cannot change the degree of reinforcement once performed or finely and easily adjust the reinforcement according to the degree of application of force. In addition, the earthquake-resistant repair is desired to be applicable not only to bridge piers, bridge girders, columns, beams, retaining walls, and other concrete structures, but also to brick masonry structures and masonry structures.

  Furthermore, it is desirable that the member for reinforcement does not take a place compared with a building, is lightweight, and does not require a large-sized machine for construction. In addition, as described above, huge earthquakes have hit the various places, and it is an urgent issue to repair existing buildings at a low cost and in a short construction period.

  Therefore, in order to solve such a problem, the present invention is easy to cope with an unexpected earthquake, the reinforcing material is lightweight, inexpensive and simple, can be constructed in a short time, and according to the degree of load It is an object of the present invention to provide a shell pipe earthquake-resistant structure and a shell pipe earthquake-proof reinforcement method which can be finely adjusted and can easily change the reinforcement after construction.

  The shell pipe earthquake-resistant structure of the present invention includes a plurality of shell pipes that are filled with a filler for improving compressive strength, and that are in contact with the side surface of the structure for earthquake resistance reinforcement, and a plurality of shell pipes and a structure. In order to unify the movement of an object during an earthquake, a shell-pipe seismic structure with a plurality of shell pipes pressed against the side of the structure, and the magnitude of the stress acting on the joint during an earthquake The main feature is that it is tightened to the structure with the tightening force, tightening position and tightening width according to the condition.

  According to the shell-pipe seismic structure and the shell-pipe seismic reinforcement method of the present invention, it is easy to cope with unexpected earthquakes, the reinforcing material is lightweight, does not require a large machine, is inexpensive and simple, and is short-term. It can be installed in between, and fine adjustment according to the degree of load can be performed, and the reinforcement after construction can be easily changed.

  According to a first aspect of the present invention, there are provided a plurality of shell pipes that are filled with a filler for improving compressive strength and that are in contact with a side surface of the structure to perform seismic reinforcement, a plurality of shell pipes, and a structure In order to integrate the movement at the time of an earthquake, a shell-pipe seismic structure with a connection body that presses a plurality of shell pipes against the side of the structure, and the connection body depends on the magnitude of the stress acting during the earthquake This is a shell-pipe seismic structure characterized in that it is fastened to the structure with the tightening force, tightening position and tightening width.It is easy to cope with unexpected earthquakes, the reinforcing material is lightweight, It requires no machine, can be constructed inexpensively and easily in a short period of time, can be finely adjusted according to the degree of load, and can easily change the reinforcement after construction.

  The second form of the present invention is a form subordinate to the first form, and when the structure is a bridge pier, the connecting body is a lower leg part, an upper leg part, a middle leg part, and a height that is 1/3 of the leg height. It is a shell-pipe seismic structure characterized in that it is tightened at at least one tightening position in the vicinity. In addition to the action of the first form, the pier can be seismically reinforced at low cost and in a short time. Fine adjustments can be made according to the degree of load, and reinforcement after construction can be easily changed.

  The third form of the present invention is a form subordinate to the first form, and when the structure is a beam, a girder or a prestressed concrete structure, the connecting body is the center part of the structure, and the end part of both ends. 2. The crust pipe earthquake-proof structure according to claim 1, wherein the structure is tightened at at least two tightening positions including one of the first, the beam, the girder, or the prestressed concrete structure. The object can be seismically reinforced in a short period of time at a low cost, making it possible to make fine adjustments according to the degree of load, and to easily change the reinforcement after construction.

  4th form of this invention is a form subordinate to 1st form, Comprising: When a structure is a retaining wall, a connection body contains at least 1 site | part or more among a standing wall lower part and a standing wall center part. A shell-pipe seismic structure characterized by being tightened at a tightening position. In addition to the action of the first form, the retaining wall can be seismically reinforced at a low cost and in a short period of time. Fine adjustments can be made, and the reinforcement after construction can be changed easily.

  A fifth form of the present invention is a form subordinate to the first or second form, and when the structure is a bridge pier, a plurality of shell pipes are provided on a footing or a footing around the pier, or a foundation or support It is a shell-pipe seismic structure that is supported by the ground and is erected in the vertical direction. In addition to the action of the first or second form, the pier can be uniformly seismically reinforced and loaded. Fine adjustments can be made according to the degree of reinforcement, and reinforcement after construction can be easily changed.

  6th form of this invention is a form subordinate to 1st-5th form, Comprising: The filler was comprised from 1 type, or 2 or more types of sand, slag, mortar, concrete, resin. It is a characteristic shell-pipe seismic structure, and in addition to the effects of the first to fifth forms, the filler can improve the compressive strength of the shell pipe, can be constructed inexpensively and easily, in a short period of time, Fine adjustments can be made according to the degree of reinforcement, and reinforcement after construction can be easily changed.

  According to a seventh aspect of the present invention, a plurality of shell pipes filled with a filler for improving compressive strength are arranged in contact with the side surface of the structure, and the movement of the plurality of shell pipes and the structure during an earthquake occurs. This is a method for seismic reinforcement of a shell pipe, in which a plurality of shell pipes are pressed against the side of the structure by a connecting body to integrate them, and connected with a tightening force, a tightening position and a tightening width according to the magnitude of stress acting during an earthquake. It is a shell-pipe seismic reinforcement method characterized by tightening the body to the structure, it is easy to cope with unexpected earthquakes, the reinforcing material is lightweight, no large machine is required, inexpensive and simple It can be constructed in a short period of time, can be finely adjusted according to the degree of load, and can easily change the reinforcement after construction.

Example 1
A crust pipe seismic structure and a crust pipe seismic reinforcement method in the case of a bridge pier as a structure in Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is an overall view of a crust pipe earthquake-proof structure for a structure according to a first embodiment of the present invention, FIG. 2 is an XX cross-sectional view of the structure of FIG. 1, and FIG. FIG. 3B is an explanatory view of a method for fixing a shell pipe that reinforces a structure, FIG. 3B is an explanatory view for fixing a shell pipe that reinforces a structure to a footing in Embodiment 1 of the present invention, and FIG. 4 is an embodiment of the present invention. It is explanatory drawing of the response by the direct type | mold earthquake of a crust pipe earthquake proof structure with respect to the structure in Example 1. FIG.

  1 to 3 (a) and 3 (b), 1 is a structure made of concrete or reinforced concrete, and the structure 1 of Example 1 is a pier made of reinforced concrete. However, the structure 1 is not limited to a bridge pier, and includes a structure having at least a pillar portion (a leg of the present invention). 2 is filled with a filler 3 (described later), and a shell pipe 3 made of a metal such as iron or a fiber reinforced synthetic resin such as FRP or glass fiber is arranged around the structure 1 for seismic reinforcement. It is a filler (see FIG. 2) such as sand, mortar, concrete, and resin that is filled in the shell pipe 2. The filler 2 may be any material that increases the compressive strength of the shell pipe 2.

  In addition, the material of the pipe of the shell pipe 2 is desirably steel from the viewpoint of strength, versatility, and cost, but other metals, fiber-reinforced synthetic resins, or the like may be used as long as the strength is sufficient. The surface may be coated with a resin so that corrosion does not proceed, such as red rust generated even when exposed to wind and rain. When a small-diameter pipe, particularly a resin pipe, is used, it is very lightweight and can be constructed by human power or a small machine, and is effective for reinforcement work in a narrow place.

  The cross-sectional shape of the shell pipe 2 is a circular pipe, which is easy to obtain and desirable. However, it is not limited to a circular shape, and may be any pipe, for example, a polygonal (cylindrical) pipe such as a quadrangular or hexagonal shape, and has a thick wall. However, it may be a pipe having a hollow portion formed at least inside. A pipe structure that has a required combination strength can be used even if it has a pipe structure. The polygonal pipe is effective because the frictional force is increased when it is pressed against the structure 1. Moreover, the external shape of a pipe and the shape of a hollow part may change in the middle of a longitudinal direction. That is, a pipe having a uniform cross-sectional shape in the longitudinal direction is also suitable as a material, but a pipe in which nodes (irregularities) are formed in the middle like bamboo, or a pipe wound in the longitudinal direction, for example, a spiral shape A pipe having a cross-sectional shape whose cross section changes is also suitable. Thereby, it becomes possible to increase the adhesive force (friction, pressure welding, force by biting) with concrete. Winding or the like may be performed using two or more kinds of materials in which a synthetic resin is wound around a steel pipe to provide a node (unevenness).

  Such a shell pipe 2 can relieve an impact by the action of this adhesive force even when an impulse-like earthquake is input to the structure 1 in the vertical direction like a direct earthquake. In addition, the shell pipe 2 can increase the cross-sectional secondary moment by wrapping or spiraling as described above, and even when a bending moment due to an earthquake is applied to the structure 1, the structure 1. The shearing force acting on can be reduced. In addition, since the shell pipe 2 is only a subordinate structure for reinforcing the structure 1, a long pipe that does not occupy much space is desirable. That is, a pipe having a longer length in the longitudinal direction than the average value of two representative sides in two orthogonal directions in the cross-sectional shape is desirable.

  Next, as the filler 3 that fills the hollow portion of the shell pipe 2, a material having a high proof strength against external compression is filled. Generally, the proof stress is steel> mortar / concrete, and there are various types of resins. Therefore, the filler 3 is selected depending on what is used for the material of the shell pipe 2. However, since an expensive material does not make sense to fill the filler 3, an inexpensive material such as sand, mortar using a cement hydrate reaction, concrete, or resin is desirable. The monolithic object such as a round bar is generally high in cost and is heavy, so the problem of transportation and the like remains, and the shell pipe 2 filled with low-strength concrete in the concrete pipe is in terms of strength. Issues remain.

  The shell pipe 2 has a skeleton part (pipe) formed on the outer periphery of the filler 3, so that the inner filler 3 takes on this external force and deforms against a force that causes plastic deformation such as compression. The pipe of the skeleton part takes over the external force and supports it. As a result, when an external force is applied to the pipe, the filler suppresses the deformation of the pipe shape, and the two materials share the function, thereby providing a structure having a large proof strength against the external force. The pipe and the filler 3 cover the weak points of physical strength, and as a whole, the strength is equal to or close to that of a solid bar.

  This can be understood from the following familiar cases. Skeletal structures such as humans, mammals and birds have a structure in which muscles are formed around bones. However, insects have a structure with a shell on the outside and a muscle on the inside. The secret of insects, which are several to tens of times stronger than humans when converted to scale, lies in this shell structure. In a normal reinforced concrete structure, concrete corresponds to muscles, and reinforcing bars correspond to skeletons. However, the shell pipe 2 of Example 1 is a steel pipe on the outside, and the inside is a shell structure such as concrete or mortar. The structure is stronger than reinforced concrete against external forces.

  Therefore, when an unexpected force such as an earthquake is applied suddenly and a torsion or excessive repetitive force is applied, the shell pipe 2 exhibits higher earthquake resistance than the reinforced concrete structure. That is, the toughness (deformation performance) of the structure 1 can be improved. The shell pipe 2 is easy to manufacture by allowing the filler 3 to flow into the pipe later, but the elongated filler 3 is manufactured, and then a thick portion (pipe portion) is formed on the outside. It may be manufactured by wrapping around. For example, a pipe in which a steel rod as the filler 3 is manufactured and a high-strength steel plate is wound around the steel rod or a reinforcing fiber sheet such as carbon fiber around the filler 3 made of recycled resin may be used.

  In addition, seismic reinforcement is not only retroactively retrofitted to existing buildings, but the structure of the shell pipe structure of Example 1 is installed in a structure 1 such as a pillar in a new building. It can also be used as an alternative material that reduces the burden on the steel frame and reinforcing bar of the object 1, and in this case, the construction period can be shortened, and a seismic reinforcement structure can be easily produced at low cost.

  In FIGS. 1 and 2, 4 a, 4 b, and 4 c are wound around a plurality of crust pipes 2 installed in close contact with the periphery of the structure 1, and the plurality of crust pipes 2 are tightened. It is a connection band (the connection body of the present invention) for integrating (interlocking) the movement of the shell pipe 2 of the structure 1. Both ends of the connecting bands 4a, 4b, 4c are wound in a single or multiple manner, and then fixed by adhesion, welding, bolting, clips, rope knots, or the like.

  Although the structure 1 of Example 1 is a pier, the connection belt | band | zone 4a is provided in the pillar lower part (lower leg of this invention) of a bridge pier in which a brittle fracture occurs most frequently when the horizontal force of an earthquake acts, and thereby The shell pipe 2 is fastened to the structure 1. In addition, a bandage 4b is provided in the central part of the column (the central part of the leg of the present invention) where destruction occurs at the following frequency or in the vicinity of 1/3 of the leg height, and the shell pipe 2 is fastened to the structure 1. Further, a connecting band 4b is provided at the upper part of the column (the upper part of the leg of the present invention) to fasten the shell pipe 2 to the structure 1. These tightening positions are positions where the stress acting during an earthquake is predicted to exceed an allowable value.

  By the way, when an earthquake force is applied, the position where the structure 1 is broken differs depending on the structural characteristics of the structure 1. In the case of the structure 1 having the column portion as in the case of the pier, when a horizontal force acts on a portion having a large mass, the inertial force causes the largest bending moment to be applied to the column lower portion and the column 1 is destroyed from the column lower portion. In the case of the structure 1 in which a distributed load that gradually increases toward the lower part of the column acts, the structure 1 is destroyed by applying a maximum bending moment to a position about 1/3 of the height from the lower part of the column. In addition, when a vertical movement force is applied, a large stress is often applied to the central portion of the column, then the lower portion of the column, and the upper portion of the column.

  However, the shell-pipe seismic structure of Example 1 is characterized in that the tightening force (tightening force) of the connection bands 4a, 4b, 4c, the tightening position and the tightening width where the connection bands 4a, 4b, 4c are installed are the characteristics of the structure 1. Since the portion (width) greater than or equal to the predetermined stress is tightened by the connecting bands 4a, 4b, and 4c, with the center where the maximum stress is applied to the structure 1, the structure 1 The degree of reinforcement can be easily adjusted according to the structural characteristics.

  As described above, in the first embodiment, the connecting bands 4a, 4b, and 4c are provided at the three tightening positions with the predetermined width and the predetermined tightening force, but the column lower part, the column upper part, the column central part, and the leg height 1 The tightening may be performed at the tightening position of at least one part in the vicinity of the height of / 3. The number of installation locations may be further increased, or depending on the structure, only the connection band 4a at the lower part of the column, which is the most loaded, or only the connection bands 4a and 4b at the lower part of the column and the center of the column may be tightened. . In addition, the connecting bands 4a, 4b, and 4c can be configured using a shell pipe having the same configuration as the shell pipe 2.

  The connecting bands 4a, 4b, and 4c are preferably wires (made of metal or fiber reinforced resin as a main material), cloths made of fiber reinforced resin such as carbon plate as a main material, band iron by tightening iron plate bolts, ropes, etc. Thus, the tightening force of the structure 1 and the plurality of shell pipes 2 by the connecting bands 4a, 4b, 4c is that the shell pipe 2 restrains the structure 1 at the time of an earthquake (resisting force is generated by friction, pressure welding, and biting). Should be able to exercise together. In the first embodiment, the connection band 4a is wire wound, the connection band 4b is cross-winding, and the connection band 4c is band-wound. Of course, it is not limited to this. The connection bands 4a, 4b, and 4c need only have a sufficient adhesive force (friction, pressure contact, and force due to biting) that can be interlocked with the structure 1, and are provided at the lower part of the column and the central part of the column shown in FIG. The bands 4a and 4b are wider than the column top.

  In the case of the pier of the first embodiment, the length of the crust pipe 2 is preferably equal to the height of the leg portion. However, in the situation of the structure 1, for example, even the height to the center of the column may be a column. It may be the height only at the bottom. However, in this case, when the horizontal force of the earthquake acts, the leg part will sway due to the weight of the pier, and the shell pipe 2 may be buckled, so it is preferable to make it higher than half the pier leg if possible. .

  Next, as shown in FIGS. 1, 3 (a) and 3 (b), 5 is a footing of the structure 1, and 6 is the ground surface. Further, in FIG. 3 (a), reference numeral 7 denotes a support portion formed by arranging a plurality of shell pipes 2 on the footing 5 around the structure 1 and placing concrete on the form of the leg, Reference numeral 8 shown in FIG. 3B denotes a plurality of insertion holes formed on the footing 5. The lower end of the shell pipe 2 is inserted into the insertion hole 8 and is firmly fixed with polymer concrete, polymer mortar, concrete, mortar, resin or the like. As a result, the plurality of shell pipes 2 are reliably supported by the footing of the structure 1 or the foundation or support ground provided in the footing.

  Here, the effect | action of the crust pipe earthquake-proof structure of Example 1 is demonstrated in detail. As shown in FIG. 2, a plurality of shell pipes 2 are erected in contact with the periphery of the legs of the structure 1 and are connected by connecting bands 4a, 4b, and 4c. First, a case where horizontal seismic force is applied will be described.

  When the ground moves horizontally due to an earthquake, an inertial force acts on the heavy portion of the structure 1 and the leg portion is greatly bent. When the leg portion has a rectangular cross section with a width b and a height h as shown in FIG. 2, if this inertial force, that is, a shearing force F acts on the surface with the width b, the leg and the shell pipe 2 are It will bend like a combination beam.

Here, the longitudinal elastic modulus of the shell pipe 2 is Ep, the longitudinal elastic modulus of the pier is Ec, the secondary moment of section of the shell pipe 2 is Ip, the secondary moment of inertia of the pier leg is Ic, and the number of shell pipes 2 Where n is the cross-sectional area Ap of one shell pipe 2 and the maximum shear stress τ acting on the pier leg is generated near the center of the lower part of the column. ^{) (Ec · b · h 2} /8 + Ep · n · Ap · h / 2 · h / (b + h)) / (Ec · Ic + n · Ep · Ip) becomes extent. The strain accompanying bending is proportional to the distance from the neutral axis, the sum of the compressive stress and tensile stress acting on the entire cross section is 0, and the shear stress τ is distributed almost uniformly in the width b direction. The longitudinal elastic modulus Ec of the pier is an apparent value when reinforced concrete is used. The crust pipes 2 arranged in a direction parallel to the direction of the shearing force F are h · n / (b + h) out of n, and the remaining b · n / (b + h) are against bending of the pier. The main resistance shall be indicated.

In contrast, since the maximum shear stress .tau.c when no reinforcement is approximately ^{F · h 2/8 · Ic} , τ = τc · (1 + α · 4n · γ · h / (b + h)) / (1 + α · β N) Where α = Ep / Ec, β = Ip / Ic, γ = Ap / Ac, Ac = b · h, where α is usually about α = 15 and β is the shape and size of the shell pipe 2 and the building. by.

Assuming that the shell pipe 2 has a second moment of section that can be approximated to a round bar having a diameter d by the action of the filler 3, in order to set the maximum shear stress τ to τ <τc, 4γ · h / (b + h) < It may be about β. For example, in the case of the ^{pier, h 3/32 (b +} h) < may be a ^{d 2.} When the pier leg is a square with b = h, the reference value is about d> h / 8. However, this value is based on an approximation because the present invention is a new reinforcing method, and a reinforcing method such as a conventional fiber sheet or carbon fiber, or a reinforcing steel design method is not established as in the steel sheet turning method. It is only a guide.

  Actually, the calculation with high accuracy is complicated, and the adhesion force to the pier of the crust pipe 2 differs depending on the tightening of the connection bands 4a, 4b, 4c, and it is arranged in the plane direction parallel to the shearing force F ignored in the above calculation. The h · n / (b + h) shell pipes 2 function as resistance, and these share the shearing force F and bending moment acting on the pier, and the shape and material of the pipe and the material of the filler 3 Depending on the choice, these values will vary and will differ in each case. Therefore, in practice, τ <τc can be sufficiently realized by setting the height h or width b to 1/30 to 1/15 or more, and if the body strength is expected to be 1/40 or more. .

Next, an explanation will be given of when an impulse-like vibration in the vertical direction is input to the pier in a direct earthquake. If the mass of the pier is M, the damping coefficient due to the adhesion force of the shell pipe (the friction, pressure, and biting force due to the pipes being fastened to the connecting bands 4a, 4b, 4c) is c, and the spring coefficient of the pier is k, The response of the pier when there is an input due to an earthquake can be considered as a vibration of sin (qt) having an amplitude of (1 / Mq) · e− ^ξωt . Here, ω = (k / M) ^1/2 , ξ = c / 2 · (Mk) ^1/2 , and q = ω (1-ξ ² ) ^1/2 . In FIG. 4, Mω · h (t) indicates the amount of change in the vertical direction of the pier. When the crust pipe 2 comes into close contact with the pier and bites in, the ξ, that is, the damping coefficient c increases, and the amplitude of the transient response decreases as shown in FIG. 4 and the resistance increases.

  That is, when the vertical motion of the earthquake is inputted and the pier tries to move with inertia, the crust pipe 2 resists this movement with adhesive force. At this time, the shell pipe 2 receives a large compressive force from the pier, but the force is evenly distributed over the entire shell pipe 2 by the connection bands 4a, 4b, and 4c. Since the pipe is filled with the filler 3, it can withstand compression and avoid buckling than a simple pipe. In addition, even if buckling occurs, if the pier itself is not destroyed, the crust pipe seismic structure has fully fulfilled its role, and repairing the crust pipe seismic structure will damage the pier body. Compared to the case, it is extremely easy and inexpensive enough to be ignored.

  An actual earthquake is rare when only the force due to the vertical movement of the impulse-shaped ground described above is applied, and when the vertical and horizontal forces are applied back and forth, or mainly the horizontal force is applied. In many cases, the crust pipe earthquake-proof structure according to the first embodiment can avoid the destruction of the pier by exerting the action in the two directions as described above.

  As described above, the crust pipe seismic structure and the crust pipe seismic reinforcement method of the first embodiment are easy to cope with unexpected earthquakes, the reinforcing material is lightweight, does not require a large machine, and is inexpensive and simple. It can be constructed in a short period of time, can be finely adjusted according to the degree of load, can easily change the reinforcement after construction, and can make earthquake-resistant repairs in a short construction period. The width which can respond to torsion and excessive repetitive force than the conventional reinforced concrete structure becomes large. And it is applicable not only to a concrete structure like a pier but also to a brick structure and a masonry structure.

  And in the case of a pier, the connection ties are tightened at a tightening position of at least one part among the column lower part, the column upper part, the column central part, and the vicinity of the height of 1/3 of the leg height. Can be seismically reinforced in a short period of time, can be finely adjusted according to the degree of load, and can easily change the reinforcement after construction.

(Example 2)
The structure in Example 2 of this invention is a beam, a girder, a prestressed concrete structure, etc., and is a crust pipe seismic structure and a crust pipe seismic reinforcement method for performing such seismic reinforcement. FIG. 5 is an overall perspective view of a shell-pipe seismic structure for a structure according to Embodiment 2 of the present invention, and FIG. 6 is a partially broken structural view of a prestressed concrete structure. In the first embodiment and the second embodiment, the same reference numerals indicate the same configuration and the description thereof is omitted.

  In FIG. 5, 4d, 4e, 4f are connecting bands (connecting body of the present invention) for tightening the shell pipe 2, 10 is a pillar of the concrete building, and 11 is a beam of the concrete building. Although FIG. 5 shows the case of the beam 11, the same applies to a girder such as a bridge girder. The shell pipe 2 is made of a metal such as iron or a fiber-reinforced synthetic resin such as FRP or glass fiber as in the first embodiment.

  In Example 2, in order to seismically reinforce the beam 11 of the concrete building, the connecting bands 4d, 4e, and 4f are wound around the beam 11 at the three ends of the beam 11 and the center, and are bonded with resin. A plurality of shell pipes 2 disposed on the lower surface of 11 are fixed. The reason for fixing at both ends and the center is that when the beam 11 is almost uniformly distributed, the maximum bending moment acts on the center of the beam 11, and this is the case when an earthquake occurs. This is because a moment from an earthquake is added. Also, both ends joined to the column 10 are also broken by receiving a large shearing force when the beam 11 moves left and right, so in the second embodiment, both ends of the beam 11 are connected by the connection bands 4d and 4f. It is reinforced. In addition, if it tightens in the tightening position of the at least 2 site | part or more including one of the center part of the beam 11 and both ends, there exists a minimum effect | action.

  The beam 11 of the second embodiment reflects the magnitude of the moment applied to the beam 11, and the central connecting band 4e is cross-stretched with the most tightening force, and the connecting bands 4d and 4f at both ends have a single cross. Adopts tension. These tightening widths may be tightened within a range that is equal to or greater than a predetermined stress. It should be noted that the shell pipe 2 only needs to have the same length in the longitudinal direction as the length of the beam 11, and is disposed along the lower surface of the beam 11, and is fastened to the beam 11 by the connection bands 4 d, 4 e, 4 f. That's fine. It is preferable that both ends of the shell pipe 2 are brought into contact with the column 10, but it may be arranged with a slight gap at both ends in consideration of buckling or the like.

  Next, FIG. 6 shows a crust pipe seismic structure and a crust pipe seismic reinforcement method for a prestressed concrete (post-tension method) structure (hereinafter, PC structure). 4g, 4h, and 4i are crosses made of fiber reinforced resin such as wires and carbon plates, main bands by iron plate bolting, connecting bands such as ropes, 13 is a PC structure, and 14 is provided in the PC structure 13. 15 is a tension steel material, 16 is a support plate that receives pressure, 17 is a grip, 18 is a cap, and 19 is a concrete support. The PC structure 13 prepares a mold in which the sheath 14 is embedded, supplies ready concrete around the sheath 14, and removes the mold after it is cured. Thereafter, the tension steel material 15 is inserted into the sheath 14 and a tensile stress is applied with a jack or the like. In this state, the end of the tension steel material 15 is fixed with the support plate 16 and the grip 17, and the sheath 14 and the tension steel material 15 are interposed. It is one that is filled with a fixing agent and cured.

  Now, the seismic reinforcement of Example 2 for the PC structure 13 is similar to the case of the beam 11 on the bottom surface of the PC structure 13 and the shell pipe 2 made of metal, fiber reinforced synthetic resin such as FRP, glass fiber or the like. The PC structure 13 and the shell pipe 2 are tightened from the surroundings by the connecting bands 4g, 4h and 4i. During an earthquake, bending is suppressed at both ends and the center of the PC structure 13, and the shell pipe 2 and the connection bands 4g, 4h, 4i are integrally reinforced.

  As described above with reference to the beam 11, the connection band 4h is resin-bonded as a cross double tension to increase the tightening force most, and the connection bands 4g and 4i at both ends are resin-bonded as a cross single tension. The length of the crustaceal pipe 2 in the longitudinal direction may be the same as the length of the PC structure 13 as long as the connection band connecting bands 4g, 4h, 4i stick to and support the bottom surface of the PC structure 13. Moreover, although it is suitable for the both ends of the crustacean pipe 2 to contact | abut the pillar 10, you may arrange | position by providing a gap | interval in both ends. The connecting bands 4g, 4h, 4i may be wire winding, band iron winding, etc. in addition to cross winding.

  Thus, the crust pipe seismic structure and the crust pipe seismic reinforcement method of Example 2 are easy to seismically reinforce beams, girders, PC structures, etc., the reinforcing material is lightweight, and a large machine is required. It is inexpensive, simple and can be constructed in a short time. Fine adjustments can be made according to the load on the structure, making it possible to easily change the reinforcement after construction and make earthquake-resistant repairs in a short construction period.

  In the beam, girder, or PC structure, the connecting band is tightened at a tightening position of at least two sites including one of the end portions of the center portion and both ends of the structure. Can be easily seismically reinforced in a short period of time, and can be finely adjusted according to the degree of load, making it easy to change the reinforcement after construction.

(Example 3)
The structure in the third embodiment of the present invention is a retaining wall, and the retaining wall often collapses at the time of an earthquake. FIG. 7A is a partially broken perspective view of a crust pipe earthquake proof structure for a structure in Example 3 of the present invention, and FIG. 7B is a YY cross-sectional view of the crust pipe earthquake proof structure of FIG. is there. In the third embodiment and the first embodiment, the same reference numerals indicate the same configuration, and the description thereof is omitted.

  7 (a) and 7 (b), 4j is a connecting body for crossing and fixing the shell pipe 2, 20 is an L-shaped retaining wall for supporting the sediment deposited on one side, and 21 is its retaining wall. It is earth and sand supported by the wall 20. The retaining wall 21 includes a vertical wall (standing wall according to the present invention) and a footing (supporting portion) that supports the vertical wall.

  Here, the connection body 4j is the same as in the first and second embodiments, such as a wire (made of metal or fiber reinforced resin as a main material), a cloth mainly made of fiber reinforced resin such as a carbon plate, or by fastening an iron plate bolt. Bands, ropes, and the like can be used, but metal or resin rods or pipes are suitable for simplifying the configuration. Among these, when the connecting body 4j is made into a pipe, the weight is reduced, and it is inexpensive to make a shell pipe similar to the strength upper shell pipe 2, and the structure is the simplest and most suitable. The retaining wall 20 may be a brick masonry structure, a masonry structure, or a tail arme.

  Next, 22 is a pressure receiving plate for pressing the connecting body 4j and the shell pipe 2 against the vertical wall surface and fixing them. Reference numeral 23 denotes a fixing plate 22, a connecting body 4 j, and an earth anchor that is fixed in the ground in order to press the shell pipe 2 against a vertical wall surface, and 24 is a fixing that fixes a tension member (wire) of the earth anchor 24 to the pressure receiving plate 22. It is a tool. In addition, when a wire, a cross, a band iron, a rope, etc. are used as the connection body 4j, it is necessary to fix not only the pressure receiving plate 22 but the edge part of the connection body 4j to the earth anchor 24, and tow.

  Since the load applied to the retaining wall 20 gradually increases as it approaches the footing, it is preferable to change the number of the connecting bodies 4j to be installed according to the vertical wall height of the retaining wall 20. It installs densely under the retaining wall 20 and sparsely installs upward. And since the soil on the front of the footing (opposite to the earth and sand in Fig. 7) is very soft and the entire retaining wall does not move forward due to the earthquake, the maximum shearing force from the earthquake is at the boundary between the vertical wall and the footing The connecting body 4j is installed at the position that becomes the boundary between the straight wall and the footing so as to be the most dense. For wires, cloths, straps, ropes, etc., the closer to the footing, the stronger and wider. In addition, since the tail pile type vertical stacked block type retaining wall is often bulging, it is preferable to install the connecting body 4j so that it is the densest in the center of the vertical wall height. That is, in the retaining wall 20, the connecting body 4j may be tightened at a plurality of tightening positions including at least one of the lower part of the vertical wall and the central part of the vertical wall, and other numbers arranged on the vertical wall. .

  Thus, the crust pipe seismic structure and the crust pipe seismic reinforcement method of Example 3 are easy to seismically reinforce the retaining wall, etc., the reinforcing material is lightweight, does not require a large machine, and is inexpensive and simple. Can be constructed in a short time. Fine adjustments can be made according to the load on the retaining wall, and it is easy to change the reinforcement after construction and to make earthquake-resistant repairs in the short construction period.

  Since the connecting body is tightened at the tightening position including at least one part of the vertical wall lower part and the vertical wall central part, the retaining wall can be seismically reinforced at a low cost and in a short period of time, and it is determined according to the degree of load. Fine adjustments can be made, and the reinforcement after construction can be changed easily.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a shell pipe earthquake-resistant structure that improves the earthquake resistance of a structure and a shell pipe earthquake-proof reinforcement method.

Overall view of the shell-pipe seismic structure for the structure in Example 1 of the present invention XX sectional view of the structure of FIG. (A) Explanatory drawing of the method of fixing the shell pipe which reinforces the structure in Example 1 of this invention, (b) Explanatory drawing which fixes the crust pipe which reinforces the structure in Example 1 of this invention to a footing. Explanatory drawing of the response by the direct type earthquake of a crust pipe earthquake proof structure to a structure in Example 1 of the present invention Whole perspective view of a shell pipe seismic structure for a structure in Example 2 of the present invention Partially broken configuration diagram of prestressed concrete structure (A) Partially fragmented perspective view of the crust pipe earthquake proof structure for the structure in Example 3 of the present invention, (b) YY sectional view of the crust pipe earthquake proof structure of (a)

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reinforced concrete structure 2 Shell pipe 3 Filler 4a, 4b, 4c, 4d, 4e, 4f, 4g, 4h, 4i Connection band 4j Connection body 5 Footing 6 Ground surface 7 Support part 8 Insertion hole 10 Column 11 Beam 13 PC structure 14 Sheath 15 Tensile steel 16 Support plate 17 Grip 18 Cap 19 Concrete support 20 Retaining wall 21 Earth and sand 22 Pressure receiving plate 23 Earth anchor 24 Fixture

Claims (7)

A plurality of crust pipes that are filled with a filler for improving compressive strength and that are in contact with the side of the structure to provide seismic reinforcement, and the crust pipes and the movement of the structure during an earthquake are integrated. A crust pipe earthquake-resistant structure comprising a connecting body that presses the plurality of crust pipes against the side surface of the structure, wherein the connecting body has a tightening force according to the magnitude of stress acting during an earthquake, A shell-pipe seismic-resistant structure characterized by being tightened to the structure at a tightening position and a tightening width. When the structure is a bridge pier, the coupling body is tightened at a tightening position of at least one part among a lower leg portion, an upper leg portion, a middle leg portion, and a height of 1/3 of the leg height. The shell pipe earthquake-proof structure according to claim 1. When the structure is a beam, a girder, or a prestressed concrete structure, the connecting body is tightened at a tightening position of at least two sites including one of the end portions of the center portion and both end portions of the structure. The shell pipe earthquake-proof structure according to claim 1, wherein 2. The shell pipe seismic resistance according to claim 1, wherein, when the structure is a retaining wall, the coupling body is tightened at a tightening position including at least one portion of the standing wall lower part and the standing wall center part. Structure. When the structure is a pier, the plurality of crust pipes are supported by a footing or a foundation provided on a footing around the pier, or are erected in a vertical direction. The shell pipe earthquake-resistant structure according to 1 or 2. The shell pipe earthquake-resistant structure according to any one of claims 1 to 5, wherein the filler is composed of one or more of sand, slag, mortar, concrete, and resin. A plurality of shell pipes filled with a filler for improving the compressive strength are arranged in contact with the side surface of the structure, and a connecting body for integrating the movement of the plurality of shell pipes and the structure during an earthquake. A method for seismic reinforcement of a crust pipe by pressing the plurality of crust pipes against the side surface of the structure, wherein the coupling body is structured with a tightening force, a tightening position and a tightening width according to the magnitude of stress acting during an earthquake. Seismic reinforcement method for shell pipes, characterized by tightening to objects.

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