Abstract: A block mold for forming a block, comprising a bottom wall, a side wall movable relative to the bottom wall, and a textured material on the side wall (e.g., near a bottom portion of the side wall) and adapted to create a textured surface on the block when the side wall is moved relative to the bottom wall. The textured material comprises abrasive particles (e.g., ten to sixty micron diamond grain) in a matrix (e.g., nickel alloy). In one embodiment, opposing first and second side surfaces of the side wall form two adjacent mold cavities, and the first and second side surfaces each include textured material (e.g., on a lower portion of the respective side surface). Preferably, the side wall includes a side surface defining a plane, and the textured material is applied to the side surface to create the textured surface that protrudes from the plane.

Abstract: A concrete building system includes a set of parallel spaced apart strip footers and one or more precast concrete sections supported by the footers in a predetermined alignment. Each precast concrete section has a top slab integrally connected to a pair of equally flared legs. Each leg depends from an end of the top slab at an effective flare angle to form a corner. The precast section includes haunch sections formed between the top slab and each leg resulting in a corner thickness greater than the uniform thickness of the angled leg to which it is integrally formed and the top member. The length of the effective span of each section varies between 60 and 90 percent of the distance between the bottom-of-leg span. The sections can be used to construct bridges, culverts, underground storage units, fluid detention units and dam structures.