Foamed glass composite material and a method for using the same

Abstract

An aircraft runway safety area for slowing an aircraft that has overrun a runway, including a brittle, nondeformable material for arresting the travel of an aircraft without catastrophically damaging the aircraft, the nondeformable material being configured to crush upon being contacted by the aircraft to effect arrest, and comprising incompressible material in the form of one or more foamed glass bodies, each respective body having a top surface, a bottom surface and oppositely disposed side surfaces, and a frangible matrix encasing the one or more foamed glass bodies, the frangible matrix fabricated to protect the incompressible material and having a breaking strength sufficient to readily break without subverting the arrestment characteristics of the incompressible material. The frangible matrix is different from the incompressible material.

What is claimed is: 
     
         1 . An aircraft runway safety area for slowing an aircraft that has overrun a runway, comprising:
 a brittle, nondeformable material for arresting the travel of an aircraft without catastrophically damaging the aircraft, the nondeformable material being configured to crush upon being contacted by the aircraft to effect arrest, and comprising incompressible material in the form of one or more foamed glass bodies, each respective body having a top surface, a bottom surface and oppositely disposed side surfaces; and   a frangible matrix encasing the one or more foamed glass bodies, the frangible matrix fabricated to protect the incompressible material and having a breaking strength sufficient to readily break without subverting the arrestment characteristics of the incompressible material;   wherein the frangible matrix is different from the incompressible material.   
     
     
         2 . The runway safety area of  claim 1  wherein the incompressible material is at least about 90 volume percent foamed glass bodies. 
     
     
         3 . The runway safety area of  claim 2  wherein the foamed glass bodies have a closed cell structure. 
     
     
         4 . The runway safety area of  claim 2  wherein the foamed glass bodies have a crush strength of between about 50 PSI and about 150 PSI. 
     
     
         5 . The runway safety area of  claim 2  wherein the foamed glass bodies have a crush strength of at least about 100 PSI, and wherein the foamed glass bodies have densities of between about 100 kg/m 3  and 180 kg/m 3 . 
     
     
         6 . The runway safety area of  claim 1  wherein the foamed glass bodies have compositions in the range of about 72 percent silica, 13 percent Na 2 O and about 10 percent CaO. 
     
     
         7 . An aircraft runway end safety area for slowing an oncoming aircraft, comprising:
 a plurality of brittle incompressible foamed glass bodies; and   a frangible matrix enveloping the respective foamed glass bodies to define a runway safety area;   wherein the frangible matrix is strong enough to readily break without subverting the arrestment characteristics of the incompressible material.   
     
     
         8 . The aircraft runway end safety area of  claim 7  wherein the frangible matrix is a concrete, and wherein the plurality of brittle incompressible foamed glass bodies make up at least 50 volume percent of the runway safety area. 
     
     
         9 . The aircraft runway end safety area of  claim 7  wherein the frangible matrix is a concrete, and wherein the plurality of brittle incompressible foamed glass bodies make up at least 75 volume percent of the runway safety area. 
     
     
         10 . The aircraft runway end safety area of  claim 7  wherein the frangible matrix is a concrete, and wherein the plurality of brittle incompressible foamed glass bodies make up at least 85 volume percent of the runway safety area. 
     
     
         11 . The aircraft runway end safety area of  claim 7  wherein the frangible matrix is a concrete, and wherein the plurality of brittle incompressible foamed glass bodies make up at least 90 volume percent of the runway safety area. 
     
     
         12 . The aircraft runway end safety area of  claim 7  wherein the foamed glass bodies have a crush strength of between about 50 PSI and about 150 PSI. 
     
     
         13 . The aircraft runway end safety area of  claim 7  wherein the foamed glass bodies have a crush strength of at least about 100 PSI, and wherein the foamed glass bodies have densities of between about 100 kg/m 3  and 180 kg/m 3 . 
     
     
         14 . The aircraft runway end safety area of  claim 7  wherein the runway safety area includes a plurality of raised ridges for slowing the forward speed of an oncoming aircraft. 
     
     
         15 . A runway safety area positioned adjacent a runway, comprising:
 a plurality of incompressible foamed glass bodies; and   a cementitious matrix covering and at least partially surrounding the respective foamed glass bodies and defining a runway safety composite;   wherein the runway safety composite has a principal compressive failure mode of crushing;   wherein the runway safety composite will preferentially crushingly fail under the compressive and torsional loads produced by an aircraft rolling over the runway safety area.   
     
     
         16 . The runway safety area of  claim 15  wherein the respective foamed glass bodies have a closed cell structure. 
     
     
         17 . The runway safety area of  claim 15  wherein the respective foamed glass bodies have a crush strength of between about 50 PSI and about 150 PSI. 
     
     
         18 . The runway safety area of  claim 15  wherein the respective foamed glass bodies have a crush strength of at least about 100 PSI, and wherein the respective foamed glass bodies have densities of between about 100 kg/m 3  and 180 kg/m 3 . 
     
     
         19 . The aircraft runway safety area of  claim 15  wherein the runway safety composite includes a plurality of raised ridges for slowing the forward speed of an oncoming aircraft.