Building block and method for producing the same

Abstract

The invention relates to a building block and a method for producing the same, which has a reduced mass by comparison with conventional building blocks and excellent insulating properties. The building block according to the invention consists of a lightweight material which is selected from expanded glass, pearlite, expanded clay or mixtures thereof. The lightweight material is obtained by liquid phase sintering or fusing of pre-expanded glass granulate, clay granulate, pearlite or mixtures thereof and forms a pore structure as an insulating core which is at least partially enclosed by a shell body formed from a conventional building block material. The building block is produced by an appropriate shell body being filled with the lightweight material, and the pre-expanded lightweight material, which has a residual expanding agent content of at least 0.1 mass % and is used in granulate form, being heated to above the softening temperature of the granulate, an additional volume expansion occurring and the granulate surfaces being fused.

1 . Building block, in which a lightweight material, which has been produced by fusing of pre-expanded glass granulate, expanded clay granulate, pearlite or mixtures thereof, with a residual content of binding agent of 0.1 to 3 mass % forms a closed-pore structure as an insulating core (2) with a bulk density ≦600 kg/m 3 , is enclosed at least partially by a shell body ( 1 ) formed from a conventional building block material.  
     
     
         2 . Building block according to  claim 1 , 
 characterised in that 
 the shell body ( 1 ) is formed from burnt loam, clay and a clay mass as well as wood-concrete, lightweight concrete formed from expanded clay, pumice or similar lightweight aggregates.  
   
     
     
         3 . Building block according to  claim 1  or  2 , 
 characterised in that the shell body ( 1 ) is partially or completely open at least at its upper end face.  
 
     
     
         4 . Building block according to one of  claims 1  to  3 , 
 characterised in that webs ( 3 ) and/or grooves are formed on the inner wall of the shell body ( 1 ).  
 
     
     
         5 . Building block according to one of  claims 1  to  4 , 
 characterised in that recesses ( 4 ) are formed on upper and/or lower end faces of the shell body ( 1 ) for reinforcing members to be led through.  
 
     
     
         6 . Building block according to one of  claims 1  to  5 , 
 characterised in that the shell body ( 1 ′,  1 ″) is configured in two parts with a plurality of longitudinal webs ( 5 ) aligned parallel to each other, in each case, adjacently in pairs, alternately air or an insulating core ( 2 ) is present between these longitudinal webs ( 5 ) and the one part of the shell body ( 1 ′) can be guided into the second part of the shell body ( 1 ″) by an appropriate meander-shaped arrangement of the insulating cores ( 2 ).  
 
     
     
         7 . Building block according to one of  claims 1  to  6 , 
 characterised in that grip recesses ( 7 ), reinforcement channels ( 10 ) and/or hollow chambers ( 8 ) are formed in the insulating core ( 2 ).  
 
     
     
         8 . Building block according to one of  claims 1  to  7 , 
 characterised in that double webs ( 9 ) are formed on the shell core ( 1 ).  
 
     
     
         9 . Building block according to one of  claims 1  to  8 , 
 characterised in that the upper and lower end faces are configured as a tongue-and-groove connection ( 11 ,  12 ).  
 
     
     
         10 . Building block according to one of  claims 1  to  9 , 
 characterised in that acoustic decoupling is present between the inner wall of the shell core ( 1 ) and the insulating core ( 2 ).  
 
     
     
         11 . Building block according to one of  claims 1  to  10 , 
 characterised in that the insulating body ( 2 ) has a bulk density ≦250 kg/m 3 .  
 
     
     
         12 . Building block according to one of  claims 1  to  11 , 
 characterised in that the insulating body ( 2 ) represents a closed-pore structure.  
 
     
     
         13 . Building block according to one of  claims 1  to  12 , 
 characterised in that lightweight aggregate particles, selected from expanded glass, pearlite and expanded clay, are interconnected in network fashion forming a soda-lime glass.  
 
     
     
         14 . Method for producing a building block according to one of  claims 1  to  13 , characterized in that the interior of a shell body ( 1 ) is filled, to at least 80% of its final volume, with thermally pre-expanded glass, thermally pre-expanded pearlite or thermally pre-expanded clay, as a granulate, with a residual expanding agent content of 0.1 to 3 mass %, and then heating is carried out up to temperatures above the softening temperature of the granulate which leads to a further volume expansion and to sintering of the granulate surfaces.  
     
     
         15 . Method for producing a building block according to one of  claims 1  to  13 , characterised in that thermally pre-expanded glass, thermally pre-expanded pearlite or thermally pre-expanded clay with a residual expanding agent content of 0.1 to 3 mass % is placed as a granulate, to at least 80% of its final volume, into a mould; then heating is carried out up to temperatures above the softening temperature of the granulate which leads to a further volume expansion and to sintering of the granulate surfaces, and the moulded article obtained is released from the mould as an insulating body ( 2 ) and pressed into a shell body ( 1 ).  
     
     
         16 . Method according to  claim 14  or  15 , 
 characterised in that a granulate with particle sizes in the range between 0.25 and 8 mm is used.  
 
     
     
         17 . Method according to one of  claims 14  to  16 , 
 characterized in that a residual content of expanding agent in the range between 0.1 and 1 mass % is maintained.  
 
     
     
         18 . Method according to one of  claims 14  to  17 , 
 characterized in that a thermally pre-expanded glass granulate, obtained from recycled glass with the addition of an organic auxiliary expanding agent, is used.  
 
     
     
         19 . Method according to  claim 18 , 
 characterised in that that sugar derivative is used as the expanding agent.    
     
     
         20 . Method according to  claim 17  or  18 , 
 characterised in that the thermal pre-expansion is so carried out that the expanding agent fraction arises as the residual content of the expanding agent.  
 
     
     
         21 . Method according to one of  claims 14  to  20 , 
 characterised in that, exploiting the heat from the firing process for producing a shell core ( 1 ), pre-heated granulate is filled into the shell core ( 1 ) and further heating is carried out until the softening temperature of the granulate is reached and the granulate surfaces fuse.