Wall element

This application is a U.S. National Stage of International Application No. PCT/EP2006/009364, filed Sep. 27, 2006, designating the United States and claiming priority from German Application No. 10 2005 048 147.7 filed Oct. 7, 2005, the disclosures of the foregoing applications being incorporated herein in their entirety.

The invention relates to a wall element in the form of a hollow precast concrete part, as well as a component kit for interconnecting structural members when erecting walls for a building, designed to withstand storms.

Factory-produced precast concrete parts have been used for more than half a century to quickly and cost-effectively erect the shell of a building. As compared to solid walls, hollow walls have the advantage that they can be stored easily and transported easier to the construction site because of the lower weight. Hollow-wall elements comprise an inside wall, an outside wall arranged parallel and at a distance thereto, as well as one or several hollow spaces between the inside wall and the outside wall. At the construction site, the relatively light-weight hollow wall element can thus be placed with the aid of a mobile crane from the truck directly onto a prepared foundation. The hollow spaces are subsequently filled completely or partially with concrete mixed at the job site. As a result, the completed walls have a load-bearing capacity, which is not inferior to that of a solid concrete wall that is poured on-site.

The known hollow wall elements for the most part are embodied as clamshell-type double wall. A hollow wall is known from International Patent Publication WO 91/028 58 A1, for example, which consists of panels that are spaced apart with the aid of spacers.

German Patent document DE 43 31 698 C2 describes a hollow wall in the form of a precast structural part, having a first wall part of concrete and a second wall part in the form of a panel, as well as a braced girder which rigidly connects the first wall part to the panel, forming a hollow space in-between. The braced girder comprises an upper member and a lower member, wherein the upper member is encased in a concrete cover with the concrete used for the first wall part.

A hollow wall is also known from patent document DE 30 03 162 A1, for which the spacing elements are embodied in the form of a ladder. Cross staves or diagonal staves are provided between posts, which define the distance and form the bars of the ladder-type spacing elements.

International Patent Publication WO 97/04195 A1 discloses a wall element embodied as a hollow concrete precast part, comprising an inside wall, an outside wall, and a number of vertical channels extending from the top to the bottom through the complete wall element.

Flat, rectangular hollow building blocks, with open hollow spaces at the bottom and at the top, are frequently used for the foundation of a prefabricated building. The dimensions for these hollow blocks are standardized. A number of such standardized hollow blocks are used for the foundation. The precast wall elements are then erected on this foundation. The building shell with one or several floors can thus be erected quickly and cost-effectively using precast concrete parts.

In regions endangered by storms such as hurricanes or tornados, special requirements demand solid construction at least for the ground floor of a building. If these requirements are to be met when using precast hollow wall elements, then a special reinforcing connection to the foundation is necessary, so that not only the vertical load burdens of the roof and/or the upper stories, but also the horizontal loads caused by the pressure of the earth and the wind can be conducted from the wall element into the stable foundation.

Starting with the content disclosed in International Patent Publication WO 97/04195 A1, it is an object of the present invention to create a wall element embodied as precast hollow concrete part, for which the wall base can be joined easily and in a secure manner to the foundation or other elements, so that traction forces can also be transferred. A component kit for interconnecting structural precast concrete parts should furthermore be provided, which makes it possible to construct at least the ground floor of a building so that it can withstand storms.

This object and other objects are solved with a wall element comprising: a hollow concrete precast part having a top and a bottom and including an inside wall, an outside wall, a wall base, and a number of vertical channels extending from the top to the bottom through hollow concrete precast part, each channel having a cross section that is tapered toward the wall base.

The objects are further accomplished with a component kit for interconnecting structural members, used for erecting the ground floor of a building and comprising: a number of ashlar hollow blocks, each having hollow spaces and a top with openings, the blocks being and arranged side-by-side to form a foundation; wall elements as described immediately above, for which the vertical channels are aligned with the hollow spaces of the blocks; and a free-flowing fill concrete that hardens inside the channels to form a wedge.

Accordingly, the wall element according to the invention has a number of vertical channels between the inside wall and the outside wall, which extend from the top to the bottom through the complete wall element and which have a cross section that is tapered toward the wall base. Once the wall elements have been erected on the foundation, concrete mixed on site or fast-curing concrete can be poured from the top into one or several of the vertical channels. Since the channels extend through the complete wall element, the filled in concrete flows through the respective channel and into the wall base region and from there can slide even further downward, until the foundation is reached or can enter into openings provided in the foundation. If the foundation consists of the aforementioned hollow blocks, then the fill concrete can flow through the channels into those hollow spaces. Conversely, any reinforcement projecting upward from the surface of the foundation, for example steel rods, can penetrate the wall element channels from below and can combine with the concrete filled into the channels to form a high-strength, reinforced steel wall anchor.

It is essential for the vertical channels inside the wall element to have a cross section that is reduced in the direction of the wall base, wherein the channel cross section is preferably tapered toward the wall base. Once the concrete filled into the channels has hardened and/or solidified, it forms a wedge that fixedly connects the wall element to the foundation. The wall element thus can no longer be lifted off the foundation and high traction forces, e.g. those occurring with a hurricane, can also be conducted via the conical walls of the channels and the concrete wedge into the foundation. The wall element embodied according to the invention is thus provided with a secure connection to the foundation, which can withstand high loads.

The proposed wall element can also be used in the same way for erecting the walls of upper floors, wherein the wall base in that case is connected to the ceiling of the floor below or directly to other wall elements.

The channels thus need only be filled with fast-hardening concrete to the level required for a secure, reinforced connection. The upper portion of a channel that is filled partially with concrete can be used for other purposes, for example for installing pipes, lines, or thermal insulation, without this resulting in a reduction of the load-bearing capacity with respect to ground pressure and wind, as compared to a solid wall.

It is advantageous if the channels inside the wall elements according to the invention have a rectangular cross section. With a wall thickness of 30 cm, for example, the channels have a thickness of 20 cm and a width of 40 cm, wherein it is also possible to have channels with a square cross section or to have round channels. The latter would then have to be embodied conically in downward direction.

Several channels are advantageously arranged parallel, side-by-side, wherein narrow webs extend between two adjacent channels, meaning between the inside wall and the outside wall. The inside walls of the channels in that case are preferably embodied smooth, so that the concrete or quick-drying concrete filled in from the top can slide downward unimpeded, if possible.