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
• • 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
• • E—FIXED CONSTRUCTIONS
  • E04—BUILDING
  • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
  • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
  • E04B1/62—Insulation or other protection; Elements or use of specified material therefor
  • E04B1/92—Protection against other undesired influences or dangers
  • E04B1/98—Protection against other undesired influences or dangers against vibrations or shocks; against mechanical destruction, e.g. by air-raids
• • 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
  • E04H9/14—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 against other dangerous influences, e.g. tornadoes, floods
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather

Definitions

• the present invention relates to a system for damping the movement of tall structures, in particular tall buildings.
• Tall structures such as high rise buildings are often constructed incorporating several structural systems to provide resistance to lateral forces.
• Each floor is supported vertically by the cores and by external and/or internal columns.
• damping energy dissipation
• Adding damping (energy dissipation) to a building reduces the dynamic response and thus the loads in the building's structural members and foundation. If sufficient damping is added to the building, structural member sizes and foundations can be reduced and the risk of the motion of a building being noticed and being uncomfortable to occupants can be reduced or eliminated.
• damping elements into a structure can lead to significant construction cost savings through the reduction of structural element sizes, and superior performance during wind and earthquake loading.
• the present invention in a first aspect seeks to provide an improved structure that incorporates damping elements.
• the present invention provides a tall structure comprising two vertically extending parts and a vertically orientated damping element, wherein the damping element is arranged to damp relative vertical movement between the two parts.
• vertically extending it is meant that the two parts have a vertical extent, preferably generally vertical when the structure is at rest. When a swaying motion occurs the parts and the damping element will of course move away from the vertical to some extent as the structure moves.
• vertically extending could be taken to mean that the parts generally support their own weight and the weight of supported floors, if any, by compression or tension action rather than bending action when the structure is at rest.
• the damping element may be any energy dissipating element or connection such as a passive viscous, visco-elastic, hysteretic or frictional damper, or an actively controlled damping mechanism.
• the relatively high levels of structural damping provided reduces the lateral forces under wind action for which tall structures have to be designed and permits the use of fewer and/or smaller structural elements and smaller foundations, reducing the construction cost, and reducing the damage sustained by the structure in an earthquake.
• the tall structure is a tall building.
• the additional damping when applied to a building reduces the perceptibility of motion of the building to occupants of the building.
• the damping element or elements is or are preferably placed within the upper 75% of the height of the structure.
• the vertically extending parts may be cores, perimeter columns, shear walls, end walls or simply be vertical elements added to the structure for damping purposes.
• the two parts may be a core and another core, or a core and perimeter columns, or between two sub parts of a column Cores, columns and shear walls are often the primary elements of existing tall structures, and as a result an existing structure may be retro-fitted with damping elements in accordance with the invention.
• the structure may include a horizontal element extending from one of the vertically extending parts, with the damping element damping relative movement between the horizontal element, more particularly the distal end of the horizontal element, and the other vertically extending part.
• Two horizontal elements may be used, one joined to each vertically extending part with the damping element joined between the horizontal elements.
• the rotation of the vertical element in combination with the length of the horizontal element magnifies the relative movement and thus the damping element can act to damp a larger relative movement, which makes the damping more effective.
• this arrangement allows damping between vertically extending parts which are spaced some distance apart.
• the horizontal elements are relatively stiff.
• the vertically extending parts comprise a core and a perimeter column and the horizontal element is a horizontally extending outrigger between the core and the column.
• the outrigger may be connected to either of the core or the column with the damping element at its free end connected to the other of the core or the column.
• the horizontal element may be relatively thin in width in the horizontal direction perpendicular to the direction of extension of the elements, i.e. it may extend in an elongate fashion from the vertical part when viewed in a floor plan of the structure.
• Preferably the horizontal element is substantially taller in side view than its width. Where the structure is a tall building the horizontal element may extend in height across more than one storey of the building. This tall thin arrangement provides a horizontal element which is stiff in the vertical direction, but which is light and cheap to construct as it is thin in plan view.
• the horizontal element also does not disrupt the floor plan of the building as it can be conveniently placed as part of a wall dividing parts of the floor plan, hi a particularly preferred embodiment the building is of the order of 60 storeys or 210 m tall, and the horizontal element extends vertically across two full storeys.
• the horizontal element may have openings forming doorways or passageways for utilities. In particular there may be doorways where the horizontal element intersects a floor level.
• a plurality of damping elements may be arranged at the same height about the vertical parts.
• the damping elements may join a single core to a plurality of perimeter columns.
• horizontal elements there may be elements generally extending in different plan directions from a core.
• the arrangement of a plurality of damping elements about the building provides additional damping in all possible directions of sway motion. In a symmetrical structure damping of this type will generally be achieved by a symmetrical damping element arrangement. In a structure with an asymmetrical floor plan an asymmetrical arrangement of dampers may be required.
• the asymmetry could be achieved, for example, by varying the number or resistance characteristics of the dampers or the size of any horizontal elements, hi the case of buildings which have different degrees of susceptibility to dynamic motions in two orthogonal directions e.g. buildings which are rectangular in plan, the damping elements may be arranged to provide more damping for sway motions in the critical direction. This could mean fewer, or lower capacity, or an absence of, damping elements acting to suppress sway motions in the less critical direction of sway.
• the vertically extending parts may be two closely spaced cores, or a core and closely spaced end wall or column with the damping element or elements connected between the parts by means of relatively short horizontal elements, corbels or brackets. In this case the relative movement of the vertical parts is a shear movement as the structure sways.
• the vertical parts are a load bearing part and a non-load bearing part provided for damping purposes.
• non-load bearing it is meant that the vertical part does not bear any significant load, other than self-weight, when the structure is at rest, i.e. the weight of the floors, cladding and imposed gravity loads structure is carried by other parts.
• the non-load bearing part mainly carries dynamic loads that arise during swaying movement of the structure. These dynamic loads are passed to the non- load bearing part by the damping element.
• the additional non-load bearing part may be placed alongside the load bearing part, with damping elements connected between brackets or short horizontal elements such as corbels on the two vertical parts. Using an additional non-load bearing vertical part in this way allows the remainder of the structure to be designed in a conventional fashion to carry the static loads.
• the present invention provides a method of providing damping for a tall structure, the structure having two vertically extending parts, the method comprising providing a vertically acting damping element which damps relative movement between the two parts.
• the term vertically extending means the same as for the first aspect of the invention.
• the vertical parts and the damping elements used in the method may incorporate the preferred features described above.
• the method may be used in the construction of a tall structure, preferably a tall building, or alternatively the method may be for retro-fitting damping elements to an existing building.
• the present invention provides a system for adding significant levels of structural damping to a tall building through the use of stiff 'outrigger' structures extending horizontally between cores or from cores to other vertical elements such as perimeter columns, the system incorporating an energy dissipating connection within the outrigger load path.
• the energy dissipating connection or damping element may be viscous (i.e. increases with velocity to the power of some exponent), visco-elastic (i.e. provides energy dissipation and stiffness), hysteretic or frictional.
• the invention provides a building comprising two parts which may move vertically relative to one another when the building sways, and a damper arranged between the two parts, which is capable of damping that relative vertical movement.
• the damper is arranged to act generally vertically to damp the movement.
• the two parts are arranged vertically, so that in a particularly preferred embodiment the damper acts in a direction generally parallel to the parts.
• the invention provides a building comprising two parts which may move relative to one another when the building sways, and a damper arranged so as to act in a direction parallel to the two parts to damp that relative movement.
• Figure 1 shows a structure in swaying motion illustrating the placement of damping elements between vertical parts
• Figure 2 illustrates a core and perimeter column structure with an outrigger
• Figure 3 is a perspective view of an embodiment of a damping element arrangement
• Figure 4 shows one of the horizontal element and damping elements of Figure 3 in side view
• Figure 5 shows a cross-sectional view of the parts shown in Figure 4
• Figure 6 is an embodiment having an outrigger
• Figure 7 is an alternative outrigger embodiment
• Figure 8 shows damping elements between two shear walls or cores
• Figure 9 shows damping elements between shear walls and end walls
• Figure 10 is a side view showing detail of a damping element in the embodiment of Figure 9,
• Figure 11 is an embodiment with a load bearing and a non-load bearing column
• Figure 12 is a floor plan of a tall building
• Figure 13 shows a tall building in side view
• Figure 14 is a floor plan at the outrigger level of a tall building
• Figure 15 is a side view of an outrigger in Figure 14.
• Figure 16 is a graph showing how damping varies with damper resistance.
• FIG 1 illustrates the principle of the present invention.
• a tall structure is illustrated schematically as having vertical parts in the form of a core 1 and perimeter column 2.
• Vertically acting damping elements 3 are placed to damp relative vertical motion between the core 1 and column 2 as the structure sways.
• the upright or at rest position of the structure is shown by the dashed lines. It will be appreciated that the amount of swaying movement has been exaggerated for illustrative purposes.
• the damping elements 3 are connected to the core via horizontal elements in the form of relatively stiff outriggers 4, which are rigidly connected to and extend horizontally from the core 1.
• Figure 2 shows a tall building similar in construction to the structure of Figure 1,.
• the core 1 and columns 2 support a number of floors 5.
• Outriggers 4 are placed at an elevated position and in accordance with an embodiment would be connected to the columns 2 at their outer ends by damping elements which are not shown.
• a core 1 and a perimeter column 2 (or another core) will at one instant in time, at the level of the outriggers 4, be at some angle, say theta, to the vertical through bending action.
• the outrigger 4 is not connected rigidly to the perimeter columns 2, but through the relatively flexible vertically acting damping element 3.
• the outrigger 4 As the outrigger 4 is relatively stiff and undergoes little deformation, its outermost end will move vertically by a linear displacement of approximately L multiplied by theta (L.theta), where L is the horizontal length from the centre of the core to the perimeter column. This will cause the damping element 3 to undergo the same displacement (L.theta). As the structure vibrates in its sway modes this relative vertical displacement will continuously vary, and the damping element 3 will change length and develop a force that will oppose the motion, thus converting kinetic energy in the structure to thermal energy in the energy dissipating device.
• Figure 3 shows a perspective view of an arrangement of horizontal elements 4 and damping elements 3 which can be used in a building of the type shown in Figure 2.
• the horizontal elements 4 are eight outriggers 4 provided in pairs symmetrically about the core 1.
• the vertical parts are the core 1 and eight perimeter columns 2, one for each outrigger 4.
• the outriggers 4 take the form of two storey deep reinforced concrete walls and three damping elements 3 (in this case viscous dampers) are provided per outrigger 4 at the connection between the outrigger 4 and the perimeter columns 2.
• Figure 4 shows a side view of one outrigger 4 showing the floor beams 5.
• a gap 6 is provided between the outrigger 4 and the lowest floor level shown.
• the outrigger 4 is the height of two floors.
• Figure 5 the gap 6 at the bottom of the outrigger 4 is shown, and another gap 6 is provided between the upper floor level shown and the outrigger. To allow the outrigger 4 to move freely it passes though a slot in the central floor level without touching the floor or floor beams 5.
• damping may be provided by one or several damping units per outrigger.
• damping element 3 is often shown or referred to, but it should be appreciated that this may be replaced by a number of damping elements 3.
• Figure 6 shows schematically the connection of a damping element 3 between an outrigger 4 and a column 2.
• Figure 7 is an alternative arrangement to that shown in Figure 6, where the outrigger 4 is joined to the column 2 and the damping element 3 is then installed between the core 1 and the outrigger 4.
• the damping elements 3 can be installed between two cores or shear walls 1 as shown in Figure 8. A number of damping elements 3 are connected to short horizontal elements 4 in the form of corbels, and provide damping between the two core structures 1 over the building height.
• Figure 9 shows a plan view with damping elements 3 provided between the 'flanges' of building cores or shear walls 1 and end walls or columns 2.
• the damping elements 3 can be supported by short horizontal corbels as in the embodiment of Figure 8, but can be simply fixed to brackets directly on the vertical parts as shown side view in Figure 10.
• a gap 6 around the floor 5 allows unimpeded relative motion between the walls 1, 2, and the two shear walls or cores 1 may be joined by an interconnecting beam 7.
• the damping elements 3 are connected to a load bearing column 2, and a non-load bearing column 8.
• the column 2 provides support for floor parts 5 and other parts of the building, whereas the non-load bearing column 8 is provided for damping purposes in order to carry dynamic loads during movement of the building, but does not carry any significant static loads.
• the damping elements 3 are joined to short horizontal elements 4 provided on the respective columns 2, 8. It will be appreciated that in alternative embodiments the column 2 of Figure 11 could be a core 1 or another vertical part of a building.
• Figures 12 to 16 show a damping system installed in a 60 storey 210 m high reinforced concrete building with two central lift-shaft core structures 1 and a number of perimeter walls and columns 2.
• Figure 12 gives a typical floor plan of a building showing cores 1 and perimeter columns 2. The plan dimensions of the tower are approximately 36m x 39m.
• the two cores 1 are connected at each floor level by conventional reinforced concrete coupling beams.
• the perimeter walls and columns 2 are also connected by floor beams 5 at each floor level.
• Figure 13 shows a cross section through the height of a tall building. This shows the central cores 1, the perimeter beams and columns 2 and outrigger wall elements 4 just over halfway up the tower.
• a floor plan at the level of the outriggers 4 is shown in Figure 14.
• the damping elements 3 are placed at the end of the outriggers 4 and connect to perimeter columns 2.
• the floor plan also shows doorways 9 formed in the outriggers 4 to allow normal use of the floors at the outrigger level.
• the damping obtainable varies as the resistance of the dampers 3 at the ends of the outriggers 4 varies.
• the damping can be obtained by the mathematical procedure known as Complex Modal Analysis, or by a steady state forced response analysis in which the problem is solved by the Direct Method. Normal modal methods are not suitable.
• Figure 16 shows how the overall added damping varies with total damper resistance C at each outrigger.
• the overall damping is expressed as the proportion of critical damping, and C is measured in force per unit relative velocity at each damper, in this case in MN /m/s.
• the two curves relate to the two orthogonal horizontal sway directions of the building.
• a building can include outrigger horizontal elements as in Figures 2 to 7 between a core and perimeter columns, as well as damping elements between two cores arranged as in Figure 8, and/or damping elements arranged as in Figures 9 or 11.

Landscapes

• Engineering & Computer Science (AREA)
• Architecture (AREA)
• Environmental & Geological Engineering (AREA)
• Business, Economics & Management (AREA)
• Emergency Management (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Buildings Adapted To Withstand Abnormal External Influences (AREA)
• Vibration Prevention Devices (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=35458511

Family Applications (1)

Country Status (8)

Families Citing this family (8)

Family Cites Families (11)

• 2005
  • 2005-10-21 GB GBGB0521542.1A patent/GB0521542D0/en not_active Ceased
• 2006
  • 2006-10-20 US US12/090,935 patent/US20090211179A1/en not_active Abandoned
  • 2006-10-20 WO PCT/GB2006/003919 patent/WO2007045900A1/en active Application Filing
  • 2006-10-20 JP JP2008536128A patent/JP2009512796A/ja active Pending
  • 2006-10-20 KR KR1020087012003A patent/KR20080075842A/ko not_active Application Discontinuation
  • 2006-10-20 EP EP06794855A patent/EP1948888A1/en not_active Withdrawn
  • 2006-10-20 CN CNA2006800391827A patent/CN101300396A/zh active Pending
  • 2006-10-20 MX MX2008004936A patent/MX2008004936A/es not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events