WO2021094982A1

WO2021094982A1 - Transportable modular structure of prefabricated elements for building construction

Info

Publication number: WO2021094982A1
Application number: PCT/IB2020/060673
Authority: WO
Inventors: Jaime Alberto FUENTES ROMERO; Federico Alejandro NUÑEZ MORENO; Martha Lucia QUINTERO RUEDA; Paula Andrea RODRIGUEZ ROMERO
Original assignee: Pontificia Universidad Javeriana
Priority date: 2019-11-15
Filing date: 2020-11-12
Publication date: 2021-05-20
Also published as: MX2022005929A; CO2019012797A1; CL2022001280A1

Abstract

The present invention relates to a transportable modular structure of prefabricated elements for building construction. The modular structure comprises columns, beams, joists and coupling parts. Advantageously, the present invention provides a transportable modular structure that can be used to provide basic housing services, wherein said structure is quick and easy to install, lightweight, reusable and structurally strong enough to withstand environmental conditions such as high winds and earthquakes.

Description

TRANSPORTABLE MODULAR STRUCTURE OF PREFABRICATED ELEMENTS FOR THE CONSTRUCTION OF BUILDINGS

FIELD OF THE INVENTION The present invention is related to the field of architecture, engineering and construction of buildings. In particular, the present invention relates to transportable modular structures that can be used to provide basic housing services. BACKGROUND OF THE INVENTION

After the occurrence of emergency situations in which people must abandon their places of residence, it is especially necessary to provide the victims with structures that provide basic housing services (protection, shelter, a place to sleep, a place to cook and health services).

In relation to temporary protection structures, in the state of the art it is found that, due to their light weight, ease of use and construction, tents that comprise structures built from interconnectable tubular members by means of connecting accessories and lightweight and waterproof materials that cover said structure.

Among this type of structures is, for example, the one taught by patent document US4558713 that relates to a structure for a temporary shelter that is easy to install and transport. However, despite the fact that these types of structures are lightweight, reusable and easy to accommodate, since they are designed for use for short periods of time, they are not sufficiently resistant to adverse environmental conditions such as strong winds or earthquakes. i On the other hand, other types of more resistant structures have been proposed in the art; for example, that disclosed by patent document US6250021 that teaches a temporary or semi-permanent shelter that can be built from folded flat components. However, these types of structures are much heavier, making it difficult to transport them. Additionally, these structures are complex to install, since they comprise a plurality of structural components that require a particular structural configuration for their assembly, as well as specialized tools.

Specifically, despite the fact that these types of buildings are for temporary use, a great effort is still required in terms of time and qualified labor for their construction.

Therefore, at present, transportable modular structures are required that allow the construction of buildings that can be used to provide basic housing services, where said structures are quick and easy to install, light, reusable and at the same time structurally resistant to support environmental conditions such as strong winds and earthquakes.

BRIEF DESCRIPTION OF THE INVENTION The structure disclosed here is a transportable modular structure of prefabricated elements for the construction of buildings that comprises a plurality of columns, beams, joists and coupling pieces that are configured in such a way that it is possible to construct highly resistant buildings of a simple way. The modular transportable structure developed contemplates the union between the elements that compose it, where the beams and the joists are connected by one or more beam-beam connections, wherein said connection comprises a plurality of connection plates. For their part, the beams are connected to the columns by coupling pieces; where said pieces Coupling plates include column connection plates, beam support cavities, beam support bases, side flanges and one or more vertical sections for connection of additional elements.

In this way, the present invention solves the need to provide a transportable modular structure that can be used to provide basic housing services, where said structure is quick and easy to install, lightweight, reusable and at the same time structurally resistant to withstand environmental conditions. such as strong winds and earthquakes. BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows a general perspective view of the complete modular structure, according to the present invention.

Figure 2 shows a beam-girder connection (5) according to a preferred embodiment of the present invention. Figure 3 corresponds to a representation of a coupling part (4) according to a preferred embodiment of the present invention.

Figure 4 represents the structural sections that make up the coupling (4).

Figure 5 represents a beam-beam connection (7) according to a preferred embodiment of the present invention.

Figure 6 shows the internal structure of a column (1), beam (2) or joist (3) according to a possible embodiment of the invention.

Figure 7 corresponds to curves of nominal strengths per bolt diameters for 15 mm thick sheet with 16 through holes. Figures 8 to 12 correspond to load vs. displacement curves in the different cycles of the couplings evaluated in one of the preferred embodiments of the invention.

Figure 13 summarizes the maximum load withstand tension for each of the couplings evaluated according to a preferred embodiment of the invention.

Figure 14 summarizes the maximum compressive resistance load for each of the couplings evaluated according to a preferred embodiment of the invention.

Figure 15 illustrates the energy dissipated Vs the displacement by each of the couplings evaluated in a preferred embodiment of the invention.

Figure 16 summarizes the stress vs. strain curves for specimens at 90 °.

Figure 17 shows a failure obtained under laboratory conditions in one of the couplings evaluated in a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

As shown in figure 1, the invention refers to a transportable modular structure of prefabricated elements for the quick and easy construction of light and structurally resistant buildings. Such a modular structure supports external forces caused, for example, by strong winds of up to 80 km / h, generating a load of 0.4 kN / m ² , and earthquakes with forces close to 80% of the acceleration of gravity, which corresponds to earthquakes of great mechanical demand in the structure.

The transportable modular structure comprises a plurality of vertically extending columns (1), longitudinally extending side beams (2), laterally extending transverse joists (3) and coupling pieces (4). In a preferred embodiment, the transverse beams (3) are connected to the beams (2) at a level close to the end of said beams (3) by means of one or more beam-beam connections (5). Preferably, and as shown in Figure 2, the beam-girder connection (5) in the structure of the invention comprises a plurality of connection plates (6) arranged in parallel on one or more lateral surfaces of the girders (3 ) and where the connecting plates (6) are attached to a beam (2).

According to an embodiment of the invention, the lateral beams (2) are connected to the columns (1) at a level close to the end of said beams (2) by means of one or more coupling pieces (4), as shown shown in figure 1. In particular, said coupling pieces (4) make it possible to secure the column (1) and the beams to prevent their displacement. In a preferred way, each of said coupling pieces (4) make it possible to secure the column (1) and the beams (2) to prevent their displacement.

In one embodiment, each coupling piece (4) comprises: column connection plates (11) that surround the column (1) at one end thereof; one or more beam support cavities (14) formed by lateral flanges (12) and one or more beam support bases (13); wherein the side flanges (12) project longitudinally from the column tie plates (11) and the beam support base (13) extends from the surface of the column tie plates (11) in a substantially perpendicular manner to the lateral flanges (12), intersecting with said lateral flanges (12) and one or more vertical sections for joining additional elements (15), as shown in figure 3.

According to a preferred embodiment of the invention, shown in Figure 4, the coupling additionally comprises a stress distribution zone (16) that provides greater structural reinforcement to the beam support (13). More preferably, said stress distribution zone (16) is trapezoidal in shape.

In a preferred embodiment the vertical joining sections of additional elements (15) can be joined, depending on their location, by example another column, to form constructions of more than one level. More particularly, the vertical joining sections of additional elements (15) can be joined to supporting structural elements such as bases or structural elements such as roofs, which allows the complete construction of the structure.

According to an embodiment of the invention, one or more beams (2) are connected to each other by means of at least one beam-beam connection (7), as represented in figure 5.

According to the invention, the coupling pieces (4) comprise a plurality of through holes to secure the column (1) and one or more beams (2).

Any vertical distance between any through hole and any edge is at least about 1/6 the height of the flange.

In another preferred embodiment, the longitudinal distance between the through holes of the flanges (12) and the end of said flanges (12) is at least 1/6 of the length of said flange.

In another preferred embodiment the vertical distance between the through holes of the coupling (4) is at least about 1/6 of the height of said flange.

In another embodiment, the longitudinal distance between the through holes of the coupling is at least about 1/3 of the length of said flange (12).

As shown in figure 6, in one embodiment of the invention the columns (1), beams (2) and joists (3) are hollow. According to a possible embodiment of the invention, said columns (1), beams (2) and joists (3) comprise structural plates (111) and one or more internal structural supports (112) that improve their resistance.

For their part, according to preferred embodiments of the invention, the columns (1), beams (2), joists (3), coupling pieces (4) and beam-beam connection (6) can be of the same material. More preferably, the material of said columns (1), beams (2), joists (3), coupling pieces (4) and beam-beam connection (6), can be: wood, chipboard, plastic, agglomerated plastic, or the like. Most preferably the material is a recycled material. According to a preferred embodiment of the invention the recycled material is polyaluminum, more particularly thermoset polyaluminum. Advantageously, when the structure is built with hardened polyaluminum, the material evolves over time with respect to the load exerted, degrading in a controlled manner after generating a maximum in cycles subsequent to the first load cycles, following protocols similar to that of the qualification of connections in steel. Thus, before the structure collapses, the typology of failures in the coupling makes it possible to anticipate possible structural risks of the construction.

Advantageously, the present invention provides a modular structure that can be demountable into components easy to transport to a desired site.

In a further aspect, the structure disclosed herein has the ability to withstand dead loads of at least 200 kgf / m ² , live loads of at least 180 kgf / m ² and maximum horizontal acceleration of at least 0.8g and their possible combinations of action. In particular, the coupling pieces (4) are capable of withstanding substantially high levels of stress. Thus, according to a preferred embodiment of the invention and surprisingly, the typology of the coupling failure makes it possible to anticipate possible structural risks before the structure collapses.

EXAMPLES

The following examples illustrate the present invention. However, it should be understood that these are not limiting, according to the knowledge of a person of ordinary skill in the art. In a preferred embodiment of the invention, a transportable modular structure of prefabricated elements for the construction of buildings was manufactured and evaluated, where thermoset polyaluminum sheets were used as material according to one of the preferred embodiments of the present invention.

To evaluate the resistance of the construction, the values established by the Colombian earthquake resistant construction regulation (NRS-10) were used as a reference, which establishes 200Kgf / m ² for dead load, 180 Kgf / m ² live load and 0.8 g of maximum horizontal acceleration as minimum stresses that a construction must withstand to be considered as earthquake resistant.

To carry out the technical tests, the following types of stress were evaluated: tearing, elasticity, shear block and rupture. Finding that the coupling, when subjected to this stress condition, would first fail due to elasticity in most cases. Based on these results, different thicknesses of the thermoset polyaluminum sheets, quantity and types of bolts were evaluated, choosing couplings made with sheets of 15 mm thick and 16 through holes with 5/8 ”bolts because the available capacity that governs The connection capacity (Rn) obtained is greater than the maximum shear obtained from the combinations of dead, live, seismic and wind loads, and the accidental moment of the beam-column coupling. The results of this test are represented in Figure 7, which shows the oval behavior (elasticity) according to the thickness of the sheet, number of perforations and diameter of the bolt.

Load vs displacement

To determine the energy dissipated by the couplings, an experimental setup was prepared in which 5 coupling pieces were tested, where each coupling piece comprised 16 through holes located between the perforations. upper and lower perforations. In this protocol, the number of cycles, the time of a cycle and the frequency of the test were taken into account, according to Table 1. A total of 18 steps were carried out, where every 5 cycles 1 step was completed, until reaching at 90 cycles.

TABLE 1: Loading protocol Number of cycles 5

1 cycle time (s) i 0

Frequency (Hz) 0.1

Once the tests were finished, the graphs of load vs displacement (figures 8 to 12) were made, noting that in each of the couplings both in compression and in tension, a stage occurs first in which there is early accommodation due to the first displacement cycles . Subsequently, a second stage occurs where the connection behaves linearly and finally a third stage occurs represented by the drop in load capacity and a considerable increase in displacement, which results in failure mechanisms of the structural connection.

This behavior shows that the couplings, as they were designed, have a capacity that evolves over time, degrading in a controlled manner. Additionally, the similar mechanical behavior in both compression and tension suggests that the structural application of the material is cyclically repetitive and suggests the ability of the design and material to function as a strong coupling.

Similarly, and when analyzing the maximum loads resisted by tension and compression (figures 13 and 14), it is evidenced that the average of the loads resisted by the tension coupling parts was 77.02 kN with a standard deviation of 6 , 81 kN and coefficient of variation of 8.84%. Likewise, the mean of the loads resisted by the compression coupling parts was 52.27 kN with a standard deviation of 5.68 kN and coefficient of variation of 10.87%. If this capacity is compared with the maximum demand estimated from the structural analysis, with respect to the design loads of the structural system (maximum shear forces of 17.2kN), it can be seen that the capacity supplied by the material is much higher, even If the lower capacities registered in connection with the coefficient of variation of 10% were taken into account, which is low for materials that can have large variations due to the nature of the material used.

The dissipated energy vs displacement (figure 15) corresponding to each of the tested coupling pieces was plotted. The dissipated energy was obtained for each cycle as the area under the curve of the load vs displacement graph. In this regard, it was observed that the energy dissipated by the coupling pieces ranges between 100 Joules and 240 Joules for displacements between 6 mm and 9 mm, with a standard deviation of 49.72 Joules and 0.74 mm respectively. Measured unit strains

These strains described the tension and compression of the material when subjected to cyclical loading, the vertical strain being the one that best characterized the material because it was in the same direction in which the load was applied. The mean of the vertical strain values for the 5 coupling pieces was 0.0029 mm / mm and the mean of the horizontal strain values for the 5 coupling pieces was 0.0018 mm / mm. The above, as can be seen in figure 16, when compared with the lowest capacity offered by the material, which occurs when the forces are applied perpendicular to the cutting and thermoforming direction (90 °), indicates that the Failure occurs in a zone of pseudo-elasticity (after elasticity), but far from the maximum rupture values of the material, providing a factor of safety to the absolute failure of the material. In other words, the failure occurs by mechanisms and strains far from the separation of the material. Failure typology

Finally, a photographic record of the tests was made during the experimental setup and after the test in order to determine the type of failure.

The first failure observed was ovaling (figure 17) in the upper holes of the coupling pieces due to the movement of the bolts during the application of cyclic loading.

After the ovaling (elasticity) occurred, in the coupling piece, cracks associated with tension appeared from the corner of the upper part of it, making the route to the lower perforations until the failure due to tension of the material was obtained. In relation to this test and the previous ones, it is therefore possible to conclude that the couplings, in addition to being highly resistant to mechanical forces, show possible structural failures before the structure has risks of collapse.

Claims

1. A modular transportable structure of prefabricated elements for the construction of buildings comprising a plurality of vertically extending columns (1), longitudinally extending side beams (2), laterally extending transverse joists (3) and pieces of coupling (4), the modular structure characterized in that: the transverse beams (3) are connected to the beams (2) at a level close to the end of said beams (3) by means of one or more beam-beam connections (5) ; wherein the beam-girder connection (5) comprises a plurality of connection plates (6) arranged in parallel on one or more lateral surfaces of the beams (3) and wherein the connection plates (6) are attached to a beam ( 2), the side beams (2) are connected to the columns (1) at a level close to the end of said beams (2) by means of one or more coupling pieces (4); wherein each of said coupling pieces (4) comprises: column connection plates (11) that surround the column (1) at one end thereof; one or more beam support cavities (14) formed by lateral flanges (12) and one or more beam support bases (13); wherein the side flanges (12) project longitudinally from the column tie plates (11) and the beam support base (13) extends from the surface of the column tie plates (11) in a substantially perpendicular manner to the lateral flanges (12), intersecting with said lateral flanges (12); and one or more vertical sections for joining additional elements (15); and where the coupling pieces (4) make it possible to secure the column (1) and the beams (2) to prevent their displacement.

The modular structure according to claim 1 wherein one or more beams (2) are connected to each other by means of at least one beam-beam connection (7).

3. The modular structure according to claim 1 wherein the coupling pieces (4) comprise through holes to secure the column (1) and one or more beams (2).

4. The modular structure according to claim 1 wherein the columns (1), beams (2) and joists (3) are hollow.

5. A coupling piece (4) comprising: column tie plates (11) surrounding the column (1) at one end thereof; one or more beam support cavities (14) formed by lateral flanges (12) and one or more beam support bases (13); wherein the side flanges (12) project longitudinally from the column tie plates (11) and the beam support base (13) extends from the surface of the column tie plates (11) in a substantially perpendicular manner to the lateral flanges (12), intersecting with said lateral flanges (12); and one or more vertical sections for joining additional elements (15); and where the coupling pieces (4) make it possible to secure the column (1) and the beams (2) to prevent their displacement.

6. The modular structure according to claim 1 wherein the columns (1), beams (2), joists (3), coupling pieces (4) and Beam-Beam connection (6) are made of recycled material.

7. The modular structure according to claim 1 wherein the recyclable material is thermoset polyaluminum.