Load transmission device

Abstract

A telescopic bar for load transmission which, if anchored in concrete slabs, creates a support between them, forming semi-rigid joints, and prevents differential settlement of the slabs, by enabling rotation in the vertical direction about a joint axis. The telescopic bar transmits a load from one slab to an adjacent slab, ensures perfect leveling of the slab surfaces, and enables removal and reuse of the slab at a later time. The telescopic bar may be used for constructing floors of easily manufactured prefabricated materials, and creates a new paradigm for the construction of roads, seaports, airports, railways, industrial areas, etc.

Claims

1. A telescopic bar (1) anchored in slabs, that creates a support between said slabs and forms semi-rigid joints, said telescopic bar (1) comprising a sheath (2), an anchoring arc (3) fixed to said sheath (2), a rack (4) fixed to a surface of said telescopic bar (1), a rotational key (9) inserted into an access chamber (6), alignment and strengthening armatures (10), and a transmission system from rotary motion into rectilinear motion, which moves said rack (4) and which is actionable from a slab surface by turning said rotational key (9), said transmission system further comprising a pinion (5) and an adjusting nut (7); wherein said telescopic bar (1) transmits a load between said slabs and prevents differential settlement of said slabs.

2. The telescopic bar (1) according to claim 1, wherein said access chamber (6) is filled with a flexible material and is sealed at said slab surface.

3. The telescopic bar (1) according to claim 1 wherein said slabs are prefabricated concrete slabs.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The description that follows is based on the appended figures which represent, without any limiting characteristic:

(2) FIG. 1A schematic perspective view of the telescopic bar object of the invention in its essential embodiment, i.e. the first described below, in which the telescopic bar for load transmission (1) is represented with a rack (4), which runs inside a sheath (2) and an anchoring arc (3), with lower and upper alignment and strengthening armatures (10) and two openings with underpass of the slabs (11).

(3) FIG. 2A schematic perspective view of a second embodiment of the invention in which the telescopic transmission bar (1) is represented, which runs inside a sheath (2) and an anchoring arc (3), with lower and upper alignment and strengthening armatures (10), a key for rotation (9) of the pinion, which will extend the telescopic bar (1), an access chamber (6) to the pinion, two openings (11) with underpass of the slabs for placement of lifting and mounting hooks, vertical ribs/guides for aligning the slabs at the assembly stage.

(4) FIG. 3An elevation view of the telescopic bar for load transmission of a second embodiment of the invention, in which all the same components of FIG. 2 are shown, but with the pinion (5) being visible.

(5) FIG. 4A perspective view of the telescopic bar of a second embodiment of the invention, in which all the same components of FIG. 3 are shown, but with the rack (4) being visible.

DETAILED DESCRIPTION OF THE INVENTION

(6) As can be seen in the figures, the bar for load transmission (1) is provided with telescopic movement inside a sheath (2). This bar (1) is provided with an anchoring arc or bar (3) which, as the name implies, is fixed to the slab represented as a dashed line.

(7) The telescopic function of the transmission bars (1) is ensured by a system which transforms the rotary motion of a part in a rectilinear motion of another part. In this particular case, it is used a system comprising a rack and pinion or an endless screw and sector system. In the illustrated case, the pinion (5) at the end of a rotation key (9), actionable from the surface of the slab, moves the rack (4) in the surface of the telescopic bar. The key (9) is inserted in an access chamber (6). The pinion (5) inserted in a box can be adjusted through an adjusting nut (7) and locked by means of a locking pin (8). This transmission system allows moving the bar from back to front, being in a sheath already pre anchored in the contiguous pre molded slab, thereby creating a semi-continuous support between said slabs.

(8) The pinion (5) can be visited from the surface of the slab through a negative in the form of cylindrical tube, coincident with the nut of the gear (pinion) and with the safety pin, for introduction of a wrench which will allow the displacement of said bar or, if rotated in the opposite direction, the retraction of the same.

(9) This access will be filled with a material easily removable a posteriori (EPS, sponge, etc.) and properly sealed at the slab surface in order to prevent the passage of liquids and diverse dirt, which in the future would prevent the proper functioning of the pinion or which would damage it.

(10) As can be understood from the previous description, the slab comprises a channel for insertion of the acceptance sheath (2) functioning as the female part of the transmission system, while the bar (1) functions as the male part of the same system. These channels for the insertion of the sheaths (2) are drawn in the bottom of the slab. Said slab further comprises upper and lower alignment and strengthening armatures (10), vertical ribs/guides for alignment during assembly of the various slabs, and two openings (11) with underpass of the slabs for placing lifting hooks and mounting the same.

(11) The acceptance sheaths (2) (female part) may be lined with a durable material (carbon fiber, etc.) and still eliminating any noise which may result from the contact of an iron bar against an iron sheath.

(12) Once the telescopic bars for load transmission (1) are alternately disposed and anchored in the base of the slabs along the backrest joints, the bending stresses in the upper edge of said slabs decrease and a rotation about its axis in the vertical direction of said joints is allowed.

(13) Thus, any unevenness in the upper joint edge formed by the separation of the slabs can be eliminable, either these slabs are pre molded or not, as aforementioned. The shear stress in the telescopic bars will be verified in order to not introduce flexion traction forces higher than the concrete slab resistance when it is subject to load.

(14) Preferred Ways of Carrying out the Invention

(15) In a first preferred embodiment of the invention, the fabrication of the slabs in bend molds is pre-defined, i.e. a perfect planimetry is maintained even when the over-elevation bend of the curves is marked. In summary, in a first embodiment the bar (1) is provided with an anchoring arc or bar (3) with fixed curvature.

(16) In a second preferred embodiment of the invention, the telescopic bars for load transmission (1) are constituted by a single piece which is anchored to the slab in the same position and alignment, and which accepts the acceptance sheaths of the adjoining slab, maintaining the same type of function as the telescopic bar.

(17) In a third preferred embodiment of the invention, the bars (1) may rotate about an axis with a limited travel, in which a bar already pre fixed in an acceptance slab and the extension of the sane is inserted in a sheath which is screwed to a rigid base, anchored in the adjoining slab. This bar (1) is placed on top of the slab and allows the construction of slabs of variable length and width, ensuring the concave and convex connections of constant radius between two planes with variable angle. Thus, the concordances between ascent and descent, respectively for higher and lower planes, allows for the in situ placement of small segments of pre molded slabs, joined together by these bars in the axis of the joints, avoiding the sophisticated fabrication of molds with side diaphragm and bases of flexible material, only possible in sophisticated industrial facilities, thus solving with the same efficacy the mentioned concordances between different planes.

(18) In a fourth preferred embodiment of the invention, the bars (1) are executed in a similar way as the third embodiment, however they have larger dimensions and are placed laterally along the thickness of the slab, where access to the top of the slab is difficult or does not allow the filling of the attachment zone of the acceptance sheaths, due to the excessive abrasion.

(19) Lisbon, May 26, 2015