Classifications

• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
  • E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
  • E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
  • E04H9/021—Bearing, supporting or connecting constructions specially adapted for such buildings
  • E04H9/022—Bearing, supporting or connecting constructions specially adapted for such buildings and comprising laminated structures of alternating elastomeric and rigid layers
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
  • E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
  • E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
  • E04H9/021—Bearing, supporting or connecting constructions specially adapted for such buildings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2202/00—Indexing codes relating to the type of spring, damper or actuator
  • B60G2202/10—Type of spring
  • B60G2202/14—Plastic spring, e.g. rubber
  • B60G2202/143—Plastic spring, e.g. rubber subjected to compression
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
  • B60G2204/10—Mounting of suspension elements
  • B60G2204/12—Mounting of springs or dampers
  • B60G2204/125—Mounting of rubber type springs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60G—VEHICLE SUSPENSION ARRANGEMENTS
  • B60G2204/00—Indexing codes related to suspensions per se or to auxiliary parts
  • B60G2204/40—Auxiliary suspension parts; Adjustment of suspensions
  • B60G2204/45—Stops limiting travel
  • B60G2204/4504—Stops limiting travel using cable or band to prevent extension

Definitions

• the present invention relates to an antiseismic connector of limited vibration for the safe seismic isolation of structures.
• a building generally comprises • a superstructure, which is above ground, and a foundation, which is embedded in the ground.
• a horizontal gap ( joint ) extends between the superstructure and the foundation and separates these two parts of the structure.
• the antiseismic connector of the present invention is disposed in the horizontal gap at the bottom of every column or wall of the superstructure, thereby creating vibration isolation of the superstructure.
• the connector connects the superstructure to the foundation so that both compressive and tension vertical loads of the superstructure are translated to the foundation and reduces the seismic force input into the superstructure.
• the connector connects the superstructure to the foundation using prestressed tendons or cables or rods (the terms ' tendon ', ' cable ', and ' rod ' are used to describe either an individual wire, strand or bar or a group of wires, strands, or bars ) .
• prestressed tendons or cables will be vertically arranged or nearly so.
• the prestressed armament cables permit the relative movement of the foundation to the superstructure. The space needed for the unrestricted movement of the cables is provided by locating the cables in casings.
• the space between the cables and the casings will be preferably free ( unbonded tensioned cables ), but it can also be filled with a soft material which permits the relative movement between the endpoints of the cables.
• the prestressed cables create horizontal recentering forces which act to return the superstructure and foundation to their pre-earthquake spatial relationship.
• the antiseismic connector can be made of the following parts : a) two iron plates of proper size and shape for the particular structure. b) a bearing between the two plates which can be made of rubber material, or spherical bearings with elastic base or not, or roller bearings with elastic base or not, or sliding interfaces, or of any other material.
• the connector is situated at the base of the pillar between the superstructure and the foundation.
• the connector could be disposed along the bottom of the wall of the superstructure or other appropriate locations and still practice the invention.
• the structure For greater protection of structures against earthquakes, or other ground excitations, the structure must be separated from the foundation with a horizontal antiseismic gap and the use of special bearings, so that the vibrations of the foundation which is solidly fixed to the ground are not transferred to the superstructure. For this reason, we studied and designed a structure system which creates a special way of supporting the superstructure on its foundation reducing the seismic force input into the superstructure.
• the connector continues to vertically interconnect the superstructure to the foundation such that the vertical loads of the superstructure ( compressive and tension forces ) are transferred to the foundation.
• the vertical interconnection is created by prestressed cables which are specially anchored to the superstructure and the foundation.
• FIG. 1 is a schematic view of the antiseismic connector of this invention.
• FIG. 2 is a schematic cross section view of the means anchoring the prestressed armament cables in the foundation or the superstructure.
• FIG. 3 and FIG. 4 is a schematic view of a second embodiment of the antiseismic connector of this invention.
• FIG. 5 is a schematic view of the operation of a pair of cylinders and a pair of unbonded tensioned prestressed cables during a ground excitation.
• FIG. 6 is a schematic view of a bearing with spherical elements.
• FIG. 7 is a schematic cross section view of a spherical element between two hard discs that can be made of steel or composites of it or other material with suitable properties and two soft discs that can be made of elastic or lead sheet or other material with suitable properties.
• FIG. 8 is a schematic cross section view of a bearing of rubber material for use with the connector for FIG. 1.
• FIG. 9 is a schematic cross section view of a sliding bearing that consists of one flat sliding interface for use with the connector for FIG. 1.
• FIG. 10 is a schematic cross section view of a building having connectors in accordance with the present invention.
• FIG. 11 shows a schematic cross section view of a joint fragment that connects the in between ends of the parts of a prestressed cable, for the case that the cable consists of more than one part.
• FIG. 12 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• FIG. 13 shows a schematic view of an alternative way of installation of the prestressed tendons wherein, both ends of the tendon are anchored in the superstructure.
• FIG. 14 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• FIG. 15 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• an antiseismic connector 100 comprises two iron plates 1 , 2 which have dimensions chosen by one skilled in the art to satisfy the demands of the structure in which the antiseismic connector will be installed.
• the distance H between the two iron plates is equal to the height H of the bearing 3 disposed between them.
• the prestressed cables 6 connect the superstructure to the foundation.
• the prestressed tendons or cables will be vertically arranged or nearly so.
• the prestressed armament cables permit the relative movement of the foundation to the superstructure.
• the space needed for the unrestricted movement of the cables is provided by locating the cables in casings 5.
• the space 20 between the cables 6 and the casings 5 will be preferably free (unbonded tensioned cables), but it can also be filled with a soft material which permits the relative movement between the endpoints of the cables.
• the number and size of the armament cables are designed to receive all vertical tension forces they may encounter at the isolation system due to overturning moments of the superstructure.
• the prestressed cables can be made of steel or its composites or synthetic material or its composites or any other material, as will be appreciate it by one of ordinary skill in this art, and can be placed at any other part of the horizontal antiseismic joint (gap) 4 and they are not limited to being located around every bearing.
• Casings 5, such as cones or cylinders, are soldered to the holes of each plate, forming corresponding pairs of an upper casing such as the cylinder 5a and a lower casing such as the cylinder 5b.
• the upper end of the prestressed tendon 6 of the antiseismic connector is anchored in the superstructure and the lower end is anchored in the foundation.
• a bearing 3 is situated wherever suitable for seismic isolation.
• the bearing may be made from metal ( as shown as numeral 7 in FIG. 3, and FIGS. 4, and 6 ), of rubber material ( as shown as numeral 3 in FIG. 1 , and FIGS. 5 and 8, 10, 12, 13, 14, 15 ) , of Polytetrafluoroethilene (PTFE) materials or its composites or steel or its composites ( FIG. 9 shows a sliding bearing with one flat sliding interface ), or other materials with suitable properties.
• PTFE Polytetrafluoroethilene
• bearing refers to any appropriate bearing unless specifically noted.
• the bearing is intended to receive and transfer all the compressive static and dynamic loads ( +P ) from the superstructure to the foundation, and additionally to create restoring forces returning the superstructure and the foundation to their pre-earthquake spatial relationship.
• the metal bearing 7 ( FIGS. 3, 4 and 6 ) can be made of at least two circular hard discs 8 that can be made of steel or of its composites or other material with suitable properties, as will be appreciate it by one of ordinary skill in this art.
• Discs 9 that can be made of hard elastic or lead or other material with suitable properties as will be appreciate it by one of ordinary skill in this art, are located between the two hard discs 8 on the internal face of each disc.
• Spherical elements 10, made of steel or synthetic material or other material with similar strength, are disposed between the hard elastic discs 9. The number of spherical elements 10 is selected to be capable of supporting all the compressive static and dynamic loads ( +P ) from the superstructure to the foundation.
• the bearing can comprise an additional part - a cap - 16 such as a cylinder that is disposed between the superstructure and the metal bearing 7.
• the cylinder can be made of metal, such as iron, or any other material with suitable properties, as will be appreciate it by one of ordinary skill in this art.
• the cylinder can be constructed of a steel cylindrical pipe whose upper end is capped with a cap 18 adapted to be attached to the bottom face of the upper plate 1 , with bolts such that it may be replaced easily.
• the lower end of the cylindrical pipe 16 is also capped with a cap 19, adapted to be attached to the upper face of the metal bearing 7, with bolts such that it may be replaced easily.
• the bearing 3 can be made of successive layers 11 of rubber or its composites or other material with suitable properties, as will be appreciate it by one of ordinary skill in this art, and reinforcing sheets 12 that can be made of steel or its composites or other material with similar strength, having dimensions determined by the properties which we want to give to the bearing.
• This creates a kind of sandwich of alternating elastic and steel plates.
• This bearing has the property, when loaded from vertical forces, to present very small compressibility, which means that the ratio of its compression stiffness to the shear stiffness is at least 400.
• the bearing reduces the seismic force input into the superstructure because of its low stiffness on shearing deformation.
• reinforcing sheets 12 in the rubber bearing is not necessary, thereby block rubber bearings can be used.
• the bearings are subjected to horizontal ground excitation, they deform horizontally reducing the seismic force input into the superstructure.
• the prestressed cables receive all vertical tension forces that may occur at the bearing level.
• the prestressed cables generate additional horizontal recentering forces to the superstructure, acting as a second line of defense for the isolation system.
• the rubber bearings must be designed in such a way as to safely transfer the vertical compressive static and dynamic loads of the superstructure to the foundation. This is of particular concern when these bearings deform horizontally due to the ground excitation of the foundation. Manufacturers of rubber bearings give all the required specifications for the design and use of appropriate bearings.
• the bearing can consist of at least one fiat or curved sliding interface that is made of Polytetrafluoroethilene (PTFE) materials or its composites or steel or other materials with suitable properties wherein, when the bearing is under the influence of horizontal forces, the bearing accommodates horizontal deformations.
• FIG. 9 shows such a bearing, that consists of one flat sliding interface. As seen in FIG. 1 , in every pair of the plates 1 , 2 of a antiseismic connector, holes are placed opposite to one another.
• Pairs of casings such as cylinders 5a, 5b are solidly mounted, such as by soldering, to the plates 1 , 2 about the holes.
• a prestressed cable ( tendon ) 6 traverses every o pair of casings interconnecting the superstructure with the foundation wherein, the casings create the recommended free space for the movement of the cables, and additionally protect the prestressed cables from environmental influences.
• FIG. 1 shows a schematic cross sectional view of one such suitable anchoring mechanism 13, that can be made of steel or its composites or synthetic material or its composites or other material with suitable properties, as will be readily understood by 0 one of ordinary skill in this art.
• the prestressed rods 6 extend through the casings and are anchored in the foundation and in the superstructure, thereby interconnecting these two parts of the structure.
• the armament cables will be stretched a minimal length due to their natural elasticity, thereby creating horizontal recentering forces which act to return the superstructure and foundation to their previous spatial relationship. This way the antiseismic connector can securely receive vertical compressive forces (through the bearing ), vertical tension forces ( through the prestressed cables ) and horizontal forces
• the prestressed armament cables can be made either of iron or of one of its alloys, or of a synthetic material or one of its alloys, or of whichever material has suitable properties, as will be appreciate it by one of ordinary skill in this art.
• the casings of an antiseismic connector have two basic characteristics : a ) their length and b ) their diameter. The dimensions of the armament cables affects these characteristics.
• the length of the casings is determined mainly by the length of the armament rods of the antiseismic connector.
• the diameter of the casing (in the case of cones the diameter of the big base, or the diameter of the cylinders ) must be designed under consideration of the following parameters : the maximum amplitude of the relative displacement of the superstructure to the foundation and the position of the horizontal gap 4, that separates the superstructure from the foundation, with respect to the anchoring points of the armament rods.
• the required diameter of the armament cables 6 - or / and their number - is determined based on the vertical tension loads from the superstructure on the antiseismic connectors.
• the length of the prestressed armament cables primarily depends on the following two factors : a ) the diameter of the cables and b) the horizontal force which has to be generated by each cable during the seismic excitation of the foundation.
• the casings and the cables of the antiseismic connector are basic elements for the correct function of the connector to all kinds of ground vibration.
• Every antiseismic connector is placed at the columns or the walls of the construction in special widening of the horizontal gap 4 that separates the superstructure from the foundation (see FIGS. 3,
• FIG. 11 shows a schematic cross section view of a joint fragment 17 that connects the in between ends of the parts of a prestressed cable, for the case that the cable consists of more than one part. It can be made of steel or its composites or synthetic material or its composites or other material with suitable properties.
• FIG. 12 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• Parts 14 that are placed in the foundation are supports that can rotate but do not permit horizontal or vertical movement.
• FIG. 13 shows a schematic view of an alternative way of installation of the prestressed tendons wherein, both ends of the tendon are anchored in the superstructure.
• Parts 14 that are placed in the foundation are supports that can rotate but do not permit any horizontal or vertical movement.
• FIG. 14 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• Parts 14, that are placed in the superstructure are supports that can rotate but do not permit any horizontal or vertical movement.
• FIG. 15 shows a schematic view of an alternative way of installation the prestressed tendons wherein, one end of the tendon is anchored in the superstructure and the other end is anchored in the foundation.
• Parts 14 that are placed in the foundation are supports that can rotate but do not permit any horizontal or vertical movement.
• the prestressed cables produce recentering forces, supporting the safety of the superstructure, and contributing to smaller residual displacements in the isolation system.

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• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Environmental & Geological Engineering (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Vibration Prevention Devices (AREA)
• Buildings Adapted To Withstand Abnormal External Influences (AREA)
• Connector Housings Or Holding Contact Members (AREA)
• Foundations (AREA)

Priority Applications (4)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10941267

Family Applications (1)

Country Status (7)

Cited By (2)

Families Citing this family (22)

Citations (5)

Family Cites Families (15)

• 1992
  • 1992-12-24 GR GR920100576A patent/GR1001450B/el not_active IP Right Cessation
• 1993
  • 1993-12-23 AU AU57136/94A patent/AU675817B2/en not_active Ceased
  • 1993-12-23 EP EP94902990A patent/EP0690948A1/en not_active Withdrawn
  • 1993-12-23 NZ NZ259020A patent/NZ259020A/en unknown
  • 1993-12-23 US US08/290,922 patent/US5669189A/en not_active Expired - Fee Related
  • 1993-12-23 WO PCT/GR1993/000022 patent/WO1994015047A1/en not_active Application Discontinuation
  • 1993-12-23 JP JP6514978A patent/JP2944217B2/ja not_active Expired - Fee Related

Patent Citations (5)

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