THE PRIOR ART When walls that are constructed in this way are subjected to the influence of weather in the form of variations in temperature and humidity, the dimensions of the wall elements also vary to an equivalent degree. If the wall elements are allowed in this case to move in a vertical direction when they expand, the risk arises that they do not return to their original positions and shapes when they shrink, resulting in, for example, gaps that remain in the wall.

The prevention of such movement in cross comer-jointed walls by means of tie-bars that pass through vertically drilled holes in the wall elements is known. The variations in humidity in such buildings and the movements that are caused by them, however, are relatively small, such that the weight of the roof is often sufficient to hold the wall elements accurately placed together.

DESCRIPTION OF THE INVENTION An object of the invention is to provide a supporting pillar of the type described in the introduction that not only provides a support for the wall but also is capable of holding the wall elements against each other.

This is achieved by the characteristics that are specified in the subsequent claims.

According to an aspect of the invention shows that the supporting pillar has a resilient tensioning device that is displaceably guided along the pillar and has a lower end that engages with the supporting pillar and an upper end that engages with an upper wall element. Thereby wall elements can be held together in a yielding manner, such that elements are allowed to expand and displace elements that lie above them, in such a manner that these elements are drawn back into place when the elements subsequently shrink.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows the rear surface of a part of a wall in the form of a noise screen that is under construction together with a supporting pillar; Fig. 2 shows the front surface of a part of a completed wall with a supporting pillar according to the invention; Fig. 3 shows an upper part of a supporting pillar according to the invention at a larger scale; and Fig. 4 shows a part of the supporting pillar according to Fig. 3 in exploded view and in partial cross-section.

DETAILED DESCRIPTION OF AN EMBODIMENT Part of a noise screen is shown in Figs. 1 and 2, generally denoted by 10. The noise screen 10 is constructed of wall sections 12,12 that are connected at the ends that meet by means of cross comer-joints or extension connectors 16 (only one such is shown). To be more precise, each wall section 12 is constructed of long, horizontal rod-shaped wall elements 14 placed on top of each other, while each cross comer-joint 16 is formed from short, horizontal rod-shaped wall elements 18 placed on top of each other. The elements 14 and 18 are connected to each other by complementary slots according to the cross

comer-joint construction principle. The short wall elements 18 are thereby arranged such that they define an inner vertical channel with a square cross-section inside each connector 16. A more detailed description of such a connector can be found in SE-C- 502056.

A vertical supporting pillar 30 (Fig. 1) for the noise screen 10 runs through the said channel in register with it. Although other types of beam are possible, the supporting pillar 30 in the preferred embodiment is comprised of an H-beam 32. The beam 32 is anchored to a foundation in a manner that is not shown.

As Figs. 3 and 4 make clear, the supporting pillar 30 has at its upper end a tensioning device 40 that is arranged to pre-tension the short 18 and long 14 wall elements placed on top of each other against each other and against a support that is not shown, and to allow limited vertical movement when these elements are subject to expansion and shrinkage.

The tensioning device 40 that functions between the noise screen 10 and the supporting pillar 30 is comprised of a spring means 42, a guiding means 50 and a pre-tensioning means 60, connected in series with each other.

In the preferred embodiment that is shown, the spring means 42 is comprised of two tensioning helical springs 46,46. Each helical spring 46 has at one, the lower, of its ends, a hook 48 that is engaged at one end to a W-shaped steel bracket 44 (Fig. 4) that is common to the two springs 46, the downwardly pointed central angled part of which is inserted into an opening 34 placed at a certain distance down on the rib 36 of the H-beam 32. The opposite, upper, end of each spring 46 has in the same way a hook 48 that is hooked onto a J-shaped bracket 52, which is welded onto the bottom of the guiding means 50.

The guiding means 50 is comprised of two sections 54,54 of L-beam that at the upper ends of their right-angled corners are welded together at a distance from each other at a vertical steel pin 56, in such a way that they define between them a guiding slot 57 that is open at the bottom (Fig. 4). When the guiding means 50 is mounted in place on the H- beam 32, the rib 36 of the latter is engaged with the guiding slot 57, while the inner

surfaces of the flanges 38,38 of the H-beam 32 are engaged in a guiding manner with the long edges of the flanges of the sections of L-beam in a way that Fig. 3 makes clear. The control unit 50 is thus in this way displaceably guided along a limited stretch of the upper end of the H-beam 32 in a manner that does not allow rotation. Furthermore, the upper end of the steel pin 56 has an outer thread 58 (Fig. 4) for engagement with the pre- tensioning device 60.

The pre-tensioning device 60 is comprised of a threaded sheath 62 in the form of a rigging screw, one end of which 66 has an internal thread and is threaded engaged with the above-mentioned outer thread 58, and the opposite end of which 66 has an internal thread and is threaded engaged with a threaded rod or threaded bolt 68 with a head 69.

The pre-tensioning is arranged to vary by rotation of the head 69 of the threaded bolt 68.

At the upper end of the tensioning device 40, the threaded bolt 68 passes through a hole in a piece of sheet metal 70 with slightly downwards sloping sides 72,72. As is shown in Fig. 2, the lower surface of the piece of sheet metal 70 engages with the upper surfaces of the terminal rod-shaped elements 20 of the wall and the terminal rod-shaped element 22 of the comer-joint.