Method for fastening anchoring means and device suitable for this purpose

Abstract

A method is described for fastening anchoring means, especially anchor rods, reinforcing iron, etc. in solid substrates by introducing a curable mortar composition and the anchoring means into a borehole provided in the solid substrate and curing the mortar composition, the curing of the mortar composition being initiated or brought about by introducing microwave energy over the anchoring means into the borehole. Furthermore, a device is described for carrying out this method, the device having an adapter unit ( 1 ), which can be connected over a coaxial cable or a waveguide ( 2 ) with the microwave generator, and a collet chuck ( 3 ), for frictionally fixing the adapter unit to the anchoring means ( 4 ) and for passing microwave energy into the mortar composition ( 7 ) present in the borehole ( 5 ) of the solid substrate ( 6 ), and a shielding ( 8 ), surrounding the collet chuck ( 3 ).

1 . Method for fastening anchoring means, especially anchor rods, reinforcing iron, etc. in solid substrates, by introducing a curable mortar composition and the anchoring means into a borehole, which is provided in the solid substrate, and curing the mortar composition, characterized in that the curing of the mortar composition is effected by passing microwave energy through anchoring means into the borehole.  
   
   
       2 . The method of  claim 1 , characterized in that the curing of the mortar composition takes place due to the homogeneous heating of the mortar composition due to the action of the microwave energy.  
   
   
       3 . The method of  claim 2 , characterized in that the homogeneous heating is brought about by dielectric and/or ferromagnetic absorption of microwave energy by the mortar composition.  
   
   
       4 . The method of  claim 3 , characterized in that the dielectric absorption of microwave energy by the mortar composition is favored by dielectrically absorbing constituents, incorporated in the mortar composition.  
   
   
       5 . The method of  claim 4 , characterized in that polar monomers, polar initiators and/or polar auxiliary materials, such as carbon black, carbon fibers, electrically conducting titanium dioxide, finely divided metallic copper, preferably with a particle size of 1 to 50 μm, and finely divided stainless steel, preferably with a particle size of 1 to 100 μm, are used as dielectrically absorbing constituents.  
   
   
       6 . The method of  claim 3 , characterized in that the ferromagnetic absorption of the microwave energy in the mortar composition is favored by ferromagnetic particles, preferably ferromagnetic mixed oxides, which are incorporated in the mortar composition.  
   
   
       7 . The method of  claim 1 , characterized in that the curing of the mortar composition takes place due to the release or activation of a necessary reactant for the curing reaction, preferably of a curing agent constituent in the mortar composition, under the action of the microwave energy.  
   
   
       8 . The method of  claim 7 , characterized in that reaction initiators and/or reaction accelerators are released in the mortar composition as curing agent components due to the action of microwave energy.  
   
   
       9 . The method of  claim 7 , characterized in that the reactants for the curing reaction, preferably the curing agent constituents, which are to be released in the mortar composition, are present in the mortar composition in microwave-sensitive microcapsules and are released from the microcapsules due to the action of microwave energy.  
   
   
       10 . The method of  claim 9 , characterized in that the release of curing agent components from the microwave-sensitive microcapsules is promoted by microwave-sensitive additives present in the microcapsules and/or in the walls of the microcapsules, and/or by introducing a blowing agent into the microcapsules.  
   
   
       11 . The method of  claim 10 , characterized in that conductive carbon blacks, carbon fibers, electrically conducting titanium dioxide, ferromagnetic particles, mixed oxides, iron oxide, finely divided metallic copper and/or finely divided stainless steel are used as microwave-sensitive additives, present in the microcapsules and/or in the walls of the microcapsules.  
   
   
       12 . The method of  claim 10 , characterized in that water, low boiling organic compounds, preferably heptane, azo compounds, hydrazine derivatives, semicarbazides, tetrazoles and/or benzoxazines are used as blowing agent's, which are present in the microcapsules.  
   
   
       13 . The method of  claim 7 , characterized in that the curing reaction is initiated, under the action of microwave energy, by microwave-sensitive quaternary ammonium salts, present in the mortar composition.  
   
   
       14 . The method of  claim 13 , characterized in that quaternary ammonium salts, which, under the action of microwave energy, release tertiary amines that accelerate the free-radical polymerization of the curing reaction, are used as microwave-sensitive quaternary ammonium salts.  
   
   
       15 . A device for curing a motor composition, comprising an adapter unit ( 1 ), which can be connected over a coaxial cable or a waveguide ( 2 ) with a microwave generator, a collet chuck ( 3 ) for frictionally fixing the adapter unit to the anchoring means ( 4 ) and for introducing microwave energy into mortar composition ( 7 ) present in the borehole ( 5 ) of the solid substrate ( 6 ), and a shielding ( 8 ) surrounding the collet chuck ( 3 ).  
   
   
       16 . The device of  claim 15 , characterized in that the collet chuck ( 3 ) and the shielding ( 8 ) are produced from metal, preferably from an elastic copper-beryllium alloy and especially from the CuBe2 alloy.  
   
   
       17 . The device of  claim 15 , characterized in that the collet chuck ( 3 ) is designed to accommodate anchoring means ( 4 ) of different diameters.  
   
   
       18 . The device of  claim 15 , characterized by an electrically conducting sieve ( 9 ), which surrounds the part of the anchoring means ( 4 ) in the borehole ( 5 ), is isolated therefrom and can be brought into contact with the adapter unit ( 1 ), for improving the efficiency of entry of the microwave energy.  
   
   
       19 . The device of  claim 18 , characterized in that the sieve ( 9 ) has openings, through which the mortar composition ( 7 ) can pass.  
   
   
       20 . The device of  claim 18 , characterized in that the sieve ( 9 ) consists of an electrically conducting material, which has insulation on the inside.  
   
   
       21 . The device of  claim 18 , characterized in that the sieve ( 9 ) has the shape of a cylinder with a diameter between the external diameter of the anchoring means and the internal diameter of the borehole, the cylinder being closed at one end and provided at the other end with a flange extending radially outward.