Reinforced concrete slabconstruction: Metal adjustable shores (temporary supports during construction) stored in racks on job site that provide structural support to concrete slabs during concrete placement and curing. With one steel section inside another, the overall length can be lengthened almost 100% of the unextended length shown here. At one end (marked with blue X) is a screw-jack that can be screwed in and out to shorten or lengthen it precisely near floor. At the other end (ends toward us in the far rack) is up toward bottom of slab. Wilshire Blvd., Los Angeles, California 2004.

Reinforced concrete slabconstruction: Metal adjustable shores (temporary supports during construction) stored in racks on job site that provide structural support to concrete slabs during concrete placement and curing. With one steel section inside another, the overall length can be lengthened almost 100% of the unextended length shown here. At one end (marked with blue X) is a screw-jack that can be screwed in and out to shorten or lengthen it precisely near floor. At the other end (ends toward us in the far rack) is up toward bottom of slab. Wilshire Blvd., Los Angeles, California 2004.