Technical field
[0001] THE present application describes dissipator panels for seismic reinforcement of
building structures, including those consisting of resistant walls of masonry and
wooden floors and heritage buildings, and relates to the respective constructive system.
Background
[0002] In the reconstruction of downtown Lisbon and, to a lesser extent, other urban agglomerations
affected by the 1755 earthquake, innovative anti-seismic provisions were introduced
deliberately and systematically. Among those provisions, it is highlighted the construction
of a three-dimensional internal structure of wood, known as "pombaline cage". The
allusion to the Marquis of Pombal is due to the responsibility attributed to him in
rebuilding Lisbon after the disaster that devastated the city in 1755.
[0003] The cage is comprised by triangular inner walls with pombaline front, also known
as pombaline frontals or simply by front and by the wooden structures of floors and
roofing. Besides the latching function of the resistant stone masonry exterior walls,
the front used to serve as a floor support and as partition walls [1].
[0004] The large-scale rehabilitation of the most vulnerable building typologies is one
of the solutions that most contributes to the mitigation of global seismic risk, justifying
the design and development of proven solutions and with additional advantages compared
with traditional methods.
[0005] The dissipator panels referred to in the present patent object correspond to a system
that allows improving the structural safety of buildings against seismic action, thus
reducing damage resulting from the referred action over the buildings.
[0006] In recent years, new systems for seismic protection in constructions have arisen,
as an alternative to the traditional approach based on exploitation of the of the
structures' ductile capacity, which implies the formation of a mechanism based on
plastic hinges that only develop at significant levels of deformation [2,3].
[0007] Currently, the constructions - the ones built from scratch and the existing - can
be endowed with seismic protection systems, that enable the prevention of severe damage,
and the limitation of losses, more effectively than the traditional approach, which
is based on exploitation of the deformation capacity of the structures beyond the
elastic limit, at the expense of more or less extensive and irreversible damage.
[0008] The new seismic protection systems allow maintaining the operability and functionality
of constructions, immediately after the occurrence of high intensity earthquakes.
They also ensure the protection of the contents, components, equipment and secondary
structural elements of constructions [4,5].
[0009] Among the protection systems, the energy dissipation systems are highlighted, which
correspond to devices designed to dissipate high levels of energy. However, none of
the solutions known in the prior art allows seismic energy dissipation capacity similar
or close to the technology now presented in this application and simultaneously it
constitutes a preconceived constructive technology with predefined mechanical characteristics,
ready to use, slightly intrusive and easy to replace.
Summary
[0010] The present application describes a dissipator panel that comprises the following
elements:
- central dissipative device (1);
- diagonals (2);
- uprights (3);
- crossbars (4);
- connections (5).
[0011] In one embodiment, the uprights of the dissipator panel are constituted by metallic
or composite material profiles and are positioned vertically between the floors of
the building.
[0012] In another embodiment, the sleepers of the sink panel are constituted by metallic
or composite material profiles and are positioned in the horizontal direction at the
level of the building floors.
[0013] In yet another embodiment, the uprights and sleepers of the sink panel form a square
or rectangular flat structure, in which intersection of the diagonals the central
dissipative device is placed and to which the diagonals, belonging to said sink panels,
are connected.
[0014] In one embodiment, the dissipator panel comprises a dissipator device connected to
four diagonals, which in turn are articulated with the crossbars and the uprights
by means of mechanical connections at the level of the floors.
[0015] In another embodiment, the diagonals of the dissipator panel are positioned in the
two diagonal directions of the parallelogram formed by the uprights and the crossbars.
[0016] In yet a further embodiment, the diagonals of the dissipator panel are built on metal
or composite material.
[0017] In one embodiment, the central dissipator device of the dissipator panel is hysteretic
or viscous type.
[0018] In yet a further embodiment, the heat dissipator panel is fixed to the floors along
its upper and lower contour.
[0019] In one embodiment, the crossbars of the dissipator panel are placed symmetrically
relative to the median plane of the structural system of the floors.
[0020] The present application further describes a seismic rehabilitation system of structures,
comprising at least one dissipator panel as described above.
[0021] Lastly, the present application further describes the building comprising at least
one dissipator panel as described above.
General description of the invention
[0022] This application discloses dissipator panels used for seismic reinforcement, allowing
increasing significantly the energy dissipation capacity of the structures and hence
improving the overall seismic behaviour of buildings.
[0023] The dissipator panels are comprised by a central dissipator device and by diagonals,
uprights, crossbars and connections, the group of these elements forming an articulated
flat structure.
[0024] The technology now presented reduces the seismic vulnerability of buildings. The
incorporation of dissipator panels on the structural system of the buildings is reflected
in the reduction of the damages resulting from the seismic action. The global seismic
behaviour of the reinforced buildings relatively to non-reinforced shows a significant
improvement, both in terms of effort, either in deformation, as well as an increase
in the energy dissipation capacity.
[0025] Additionally, the dissipator panel enables significant improvements compared to the
known solutions from the prior art, with regard to preserving the basic characteristics
of constructions and safeguarding its historical and architectural value, in case
of heritage.
[0026] The dissipator panels correspond to a slightly intrusive solution, compatible, easy
to insert in the current structural systems. The dissipator panels are slightly intrusive
since they allow the realization of minimum interventions that are compatible and
do not alter the original structural scheme, avoiding or minimizing the need for cutting
or demolition of existing structural elements.
[0027] The dissipator panels constitute a solution with reversibility characteristics as
they are installed so that they can later be removed or supplemented, if necessary,
without great difficulty and without causing significant damage to the original construction.
Upon the occurrence of an earthquake, the constituent elements of the dissipator panels
that show any deformations can easily be replaced with new elements.
[0028] To the installation work of the dissipator panels for seismic reinforcement, a higher
efficiency of the implementation in intervention work is associated, when compared
to other more common reinforcement solutions.
[0029] The conservation of buildings is an essential component of sustainable development.
Rehabilitation interventions in existing structures allow improving the performance
and lifetime. In case of old buildings, it also allows to preserve basic characteristics
and safeguard the value as architectural and historical heritage.
[0030] The practical and methodological need to assess the sustainability of construction
solutions is growing. The demand for an integrated approach that takes into account
environmental, social and economic impacts of each of the possible solutions is growing.
[0031] In this context, rehabilitation emerges as a relevant strategy, especially by allowing
mitigation of impacts associated with interventions in existing constructions. Compared
with the existing reinforcing solutions of structures, demolition and reconstruction
of buildings, with the possible use of façades and/or the option for rehabilitation
techniques based on the use of reinforced concrete and metallic structures, entail
a more serious environmental impact in terms of waste production and other emissions,
including greenhouse gases, energy consumption, water and materials.
[0032] The rehabilitation makes it possible to reuse of existing buildings, mostly located
in residential and/or urban areas urging to revitalize. In case of historic areas,
the social benefits also result from safeguarding cultural, architectural and historical
values. Interventions should enable the maintenance of the buildings authenticity,
without sacrificing all the relevant corresponding to the cultural and historical
area from which buildings are part.
[0033] With regard to existing structures inserted in seismic risk areas, sustainability
is defended by adopting proven effective measures to improve the seismic resistance
capacity of the constructions, of utmost importance in view of the associated devastating
consequences.
[0034] In rehabilitation interventions of constructions inserted in high seismicity regions
that resort to the installation of dissipator panels, performance improvement of the
existing structures is ensured and at the same time the basic characteristics of the
constructions are preserved and its architectural and historical value safeguarded,
in the case of heritage.
Brief description of the figures
[0035] For an easier understanding of the invention join the attached figures, which represent
preferred embodiments of the invention that, however, are not intended to limit the
scope of this invention.
Figure 1 illustrates a representation of the dissipator panel for seismic reinforcement and
its implementation between floors, where the indicated reference numbers represent:
- (1) central dissipator device;
- (2) diagonal;
- (3) upright;
- (4) crossbar;
- (5) connections.
Figure 2 illustrates the detail A of Figure 1, which is a detail of the constituent central
dissipator device of the dissipator panel for seismic reinforcement, where the indicated
reference numbers represent:
(1) central dissipator device;
(2) diagonal;
(5) connections.
Figure 3 illustrates the detail A of Figure 1, which is a detail of the connection between
the diagonal, the upright and crossbars at the level of the floors, of the dissipator
panel for seismic reinforcement, where the indicated reference numbers represent:
(2) diagonal;
(3) upright;
(4) cross-bar;
(5) connections.
Figure 4 illustrates the cut 1-1 of Figure 1, which represents the dissipator panel for seismic
reinforcement, where the indicated reference numbers represent:
(3) upright;
(4) cross-bar;
(5) connections.
Figure 5 illustrates the cut 2-2 of Figure 1, which represents the dissipator panel for seismic
reinforcement, where the indicated reference numbers represent:
(1) central dissipator device;
(2) diagonal;
(4) crossbar;
(5) connections.
Figure 6 illustrates the cut 3-3 of Figure 1, which represents one of the connection forms
of the dissipator panel for seismic reinforcement to the floors, where the indicated
reference numbers represent:
(2) diagonal;
(3) upright;
(4) crossbar;
(5) connections.
Figure 7 illustrates the cut 5-5 of Figure 1, which represents the dissipator panel for seismic
reinforcement, wherein the diagonal connections are illustrated, in particular, detail
of the connection between the diagonals and the central dissipator device and detail
of the connection between the diagonals, the uprights and the crossbars, where the
indicated reference numbers represent:
(1) central dissipator device;
(2) diagonal;
(5) connections.
Figure 8 illustrates the cut 4-4 of Figure 1, wherein an embodiment of the connection of the
dissipator panel for seismic reinforcement to the floors is illustrated, where the
indicated reference numbers represent:
(2) diagonal;
(3) upright;
(4) crossbar
(5) connections.
Figure 9 illustrates the detail of Figure 8, representing the detail of the connection between
the diagonal, the upright and the crossbars, at the level of the floors, of the dissipator
panel for seismic reinforcement, where the indicated reference numbers represent:
(2) diagonal;
(3) upright;
(4) crossbar
(5) connections.
Figure 10 illustrates an application of the dissipator panels for seismic reinforcement and
an embodiment of the connections to the existing structure.
Figure 11 illustrates a schematic representation of the application of dissipator panels for
seismic reinforcement.
Description of the embodiments
[0036] This application discloses dissipator panels used for seismic reinforcement, allowing
increasing significantly the energy dissipation capacity of the structures and hence
improving the overall seismic behaviour of buildings.
[0037] The incorporation of dissipator panels in buildings allows strengthening its seismic
safety. The global seismic behaviour of the reinforced buildings relatively to non-reinforced
should show an improvement both in efforts and in deformation, as well as an increase
in the energy dissipation capacity.
[0038] The conception of the new technology results from the combination of two aseismics
principles: on the one hand, the lateral latching conferred by triangular structures
and, on the other, increased energy dissipation capacity through the incorporation
of recent methodologies for seismic protection.
[0039] Additionally, the basic characteristics of the constructions reinforced with dissipator
panels are preserved since these reinforcing elements correspond to slightly intrusive
solutions and compatible with the structural functioning of the constructions. Other
distinguishing characteristics of the dissipator panels are related to the possibility
of replacing component elements and with the reversibility of the reinforcing interventions
that resort to its installation on buildings.
[0040] The dissipator panels are comprised by a central device dissipator and by diagonals,
uprights, crossbars and connections, forming the group of these elements an articulated
flat structure, such as illustrated in Figure 1. The uprights develop vertically between
floors; the crossbars are positioned in the horizontal direction at the level of the
floors. The diagonals are connected to the central dissipator device and the other
end thereof diagonals connections are established to the uprights and crossbars, at
the level of the floors.
[0041] The dissipator panels are fixed to the floors along its upper and lower contour.
Except in the case of buildings, whose structure of the floors does not allow it or
if it is an end panel, the crossbars are double and are placed symmetrically in relation
to the median plane of the thickness of the floors, pressing the constituent elements
of these floors. The pairs of crossbars are thus connected together at the level of
the floors.
[0042] All connections between the constituent elements of the dissipator panels are performed
through systems appropriate to the behaviour mode designed and dimensioned such as,
for example, bolted connections. In case deformations are displayed in the aftermath
of an earthquake, the central dissipator device or the remaining elements that make
up the dissipator panels can easily be replaced with new parts without damage.
[0043] The dissipator panels for seismic reinforcement constitute a prefabricated intervention
solution, with behavioural characteristics well defined, easy to insert into current
structural systems.
[0044] In every building, dissipator panels can be placed on one or more floors and in each
floor can be placed one or more dissipator panels. The dissipator panels can be annexed
to interior walls. On the sites of interior bays, continuity may be ensured by small
rigid elements.
[0045] The dissipator panels correspond to reinforcing elements slightly intrusive, reversible
and consistent with the structural mode of operation of the constructions, thus allowing
to meet the requirements that should respond to interventions in old buildings, in
particular, reduced intrusiveness and extent of interventions, reversibility and compatibility
with the existing. Throughout this patent application, it is considered that the dissipator
panels show reduced intrusiveness because they are panels that are slightly intrusive.
[0046] The central dissipator device belonging to the dissipator panel is comprehended by
a polygonal piece of well-defined geometry, obtained from metal or composite material,
e.g., steel, stainless steel, properly protected against corrosion steel or other
equivalent material.
[0047] The uprights used in the dissipator panel are comprised by building profiles of metallic
or composite material, positioned vertically between the floors of the building.
[0048] The crossbars used in the dissipator panel are comprised by building profiles of
metallic or composite material, positioned horizontally, at the level of the building
floors.
[0049] Diagonals used in the dissipator panel are comprised by construction profiles of
metallic or composite material, positioned in two diagonal directions of the parallelogram
formed by the uprights and the crossbars. These diagonals are destined to make the
connection of the central dissipator device to the constituent crossbars and uprights
of said dissipator panel.
[0050] Any type of screwed mechanical articulated connection, such as steel pins or other
equivalent material makes the connections between the elements of the dissipator panel.
Applications
[0051] Dissipator panels are used in seismic reinforcement interventions of buildings, aimed
at increasing its seismic safety and therefore reducing its vulnerability.
[0052] The application of the dissipator panels falls under the area of seismic structural
rehabilitation of constructions, by resorting to slightly intrusive techniques.
[0053] The panels correspond to an easy insertion solution on current structural systems
and enable, simultaneously, to perform interventions with reduced intrusiveness and
extension, reversible and compatible with the existing.
[0054] The panels are slightly intrusive, do not adulterate the basic characteristics of
the constructions, are compatible with their original structural mode of operation
and its installation is reversible.
References
[0055]
- [1] Cóias, V., Reabilitação Estrutural de Edificios Antigos, Argumentum, 2007.
- [2] Lopes, M., Sismos e Edificios, Edições Orion, 1a Edição, Julho 2008.
- [3] Guerreiro, L., Craveiro, A., Branco, M., The use of passive seismic protection in
structural rehabilitation, Progress in Structural Engineering and Materials, Vol.
8, n.° 4, Oct-Dec. 2006, Wiley InterScience.
- [4] M. Forni et al., Development of Innovative anti-Seismic Systems in the Framework of
the LessLoss European Integrated Project, 10th World Conference on Seismic Isolation,
Energy Dissipation and Active Vibrations Control of Structures, Istanbul, Turkey,
May 28-31, 2007.
- [5] Paula, R., Cóias, V., Vasques, F., Comparison between conventional and seismic isolated
buildings. Case study in the framework of LessLoss Sub-Project 6, International Seminar
"Development of innovative anti-seismic systems in the framework of the LessLoss and
other research projects", LNEC, Lisbon, 30 Outubro 2007.
[0056] The present embodiment is naturally not in any way restricted to the embodiments
described herein and a person of ordinary skill in the art can provide many modification
possibilities thereof without departing from the general idea, as defined in the claims.
[0057] The preferred embodiments described above are of course combinable with one another.
The following claims further define preferred embodiments.
1. Dissipator panel comprising a central dissipative device (1) composed of a polygonal
spindle in a metallic or composite material connected to four diagonals (2), which
in turn are articulated to the crossbars (4), positioned in the horizontal direction
at the level of the floors of a building and the uprights (3), positioned vertically
between the floors of a building, by means of mechanical connections (5) performed
at the level of the floors of a building.
2. Dissipator panel according to the preceding claim wherein the uprights (3) are constituted
by profiles in metallic or composite material.
3. Dissipator panel according to any one of the preceding claims, wherein the crossbars
(4) are constituted by profiles in metallic or composite material.
4. Dissipator panel according to any one of the preceding claims, wherein the diagonals
(2) are positioned in the two diagonal directions of the parallelogram formed by the
uprights (3) and the crossbars (4).
5. Dissipator panel according to any one of the preceding claims, wherein the diagonals
(2) are made of steel.
6. Dissipator panel according to any one of the preceding claims, characterized in that it is fixed to the floors of a building along its upper and lower contour.
7. Dissipator panel according to any one of the preceding claims, wherein the crossbars
(2) are placed symmetrically relative to the median plane of the thickness of the
floors of a building.
8. System seismic rehabilitation of structures characterized in that it comprises at least one dissipator panel as described in any one of claims 1 to
7.
9. Building characterized in that it comprises at least one dissipator panel as described in any one of claims 1 to
7.