Light-weight bridge support systems and methods of use

Abstract

A bridge support system includes a support embankment formed from at least one light-weight material. The support embankment is arranged to support and be positioned under a footing of a bridge structure. A restraining system is operatively connected to the support embankment. The restraining system includes cross-members which are angularly offset from each other and arranged to limit at least one of lateral and vertical movement of the support embankment under high levels of excitation.

What is claimed is: 
     
         1 . A bridge support system comprising:
 a support embankment formed from at least one light-weight material and arranged to support and be positioned under a footing of a bridge structure; and   a restraining system operatively connected to the support embankment, the restraining system including cross-members which are angularly offset from each other and arranged to limit at least one of lateral and vertical movement of the support embankment under high level excitation.   
     
     
         2 . The system of  claim 1 , wherein the cross-members comprise diagonal cross-members extending between the footing and a basal slab under the support embankment. 
     
     
         3 . The system of  claim 1 , wherein the cross-members comprise cables or cabling. 
     
     
         4 . The system of  claim 1 , wherein the at least one light-weight material comprises at least one of geofoam, light-weight cellular concrete, or geosynthetic reinforced soil. 
     
     
         5 . The system of  claim 1 , wherein the at least one light-weight material comprises a plurality of geofoam blocks stacked in a plurality of layers. 
     
     
         6 . The system of  claim 5 , wherein the geofoam blocks are formed of Expanded Polystyrene (EPS). 
     
     
         7 . The system of  claim 5 , wherein the EPS is EPS  22  or EPS  29 . 
     
     
         8 . The system of  claim 5 , wherein the support embankment has a generally rectangular prismatic shape. 
     
     
         9 . The system of  claim 5 , wherein the support embankment has a generally trapezoidal prismatic shape. 
     
     
         10 . The system of  claim 5 , wherein the support embankment includes a bottom portion positionable on a soft soil. 
     
     
         11 . The system of  claim 5 , wherein the support embankment includes a bottom portion embedded in foundation soil below the support embankment. 
     
     
         12 . The system of  claim 7 , wherein the support embankment includes one or more shear keys arranged to interrupt the formation of continuous horizontal slide planes between adjacent ones of the layers of the geofoam blocks. 
     
     
         13 . The system of  claim 12 , wherein at least one of the shear keys comprises a half-height geofoam block. 
     
     
         14 . The system of  claim 5 , wherein at least some of the layers of the geofoam blocks are attached to one another via an adhesive to prevent interlayer sliding. 
     
     
         15 . The system of  claim 1 , further comprising a bridge structure including at least one footing positioned on a top portion of the support embankment. 
     
     
         16 . A bridge system comprising:
 a bridge structure including at least one footing;   a support embankment formed from geofoam material and directly supporting the bridge structure via the at least one footing engaging the support embankment; and   a restraining system operatively connected to the support embankment, and arranged to limit at least one of lateral and vertical movement of the geofoam embankment under seismic excitation.   
     
     
         17 . The system of  claim 16 , wherein the restraining system includes first and second members placed externally on the geofoam embankment. 
     
     
         18 . The system of  claim 17 , wherein the first and second members extend between the at least one footing and a basal slab under the geofoam embankment. 
     
     
         19 . The system of  claim 17 , wherein the first and second members are diagonal cross-members which are angularly offset from each other. 
     
     
         20 . A bridge support system comprising:
 a support embankment formed from a plurality of geofoam blocks stacked in a plurality of layers, the support embankment arranged to support and be positioned under a footing of a bridge structure;   one or more shear keys disposed between the geofoam blocks and arranged to interrupt the formation of continuous horizontal slide planes between adjacent ones of the layers of the geofoam blocks; and   a restraining system operatively connected to the support embankment, the restraining system including diagonal cross-members which are angularly offset from each other and arranged to limit at least one of lateral and vertical movement of the support embankment under high level excitation.