Patent ID: 7305798

Claim:
An overfilled arch structure comprising: overfill material; a void area formed in the overfill material, the void area having a lower pathway surface, first and second generally vertical sidewalls extending upward from the lower pathway surface, the first and second sidewalls spaced apart by the lower pathway surface; and an arch spanning the void area, a first end of the arch extending over, and outward beyond the first sidewall and positioned in a non-contacting relationship relative to the first sidewall, the second end of the arch extending over, and outward beyond the second sidewall and positioned in a non-contacting relationship relative to the second sidewall, the arch includes a first arch-shaped layer of precast concrete having a lower surface exposed to the lower pathway surface and a second arch-shaped layer of cast-in-place concrete contiguous with upper surface of the first layer across substantially an entirety of a span of the arch.