Concrete, Masonry Construction, and Formwork
This section sets forth the requirements for concrete, masonry construction, and formwork. It specifically addresses plant and equipment, concrete conveyance systems, reinforcing steel, surface preparation, formwork and falsework, vertical shoring, tubular welded frame shoring, tube and coupler shoring, single-post shores, vertical slip forms, releasing and moving forms, precast concrete, lift-slab, and masonry construction.
Plant and Equipment
General. Design, operate, and maintain all equipment, facilities, and formwork for concrete and masonry construction according to the requirements of this section, other applicable parts of these standards, the subsection, “Other Mechanized Construction Equipment,” and the current edition of ANSI A10.9, “Construction and Demolition Operations—Concrete and Masonry Work.”
Batching and Screening Plants. Design and construct concrete batching and screening plants, aggregate production plants, hoppers, bins, silos, and related equipment with an adequate safety factor to prevent structural failure or collapse. Refer to the subsection, “Other Mechanized Construction Equipment” for certification requirements.
Design and equip batching plants, aggregate plants, and conveyor systems with mechanical dust control systems and water spray systems (or other acceptable means) to keep airborne dust concentrations within acceptable exposure limits. Comply with permit-required confined space and hazardous energy control procedures when entering silos, storage bins, tunnels, shafts, or similar enclosed areas.
Bulk Storage Bins. Bulk storage bins, containers, and silos must have conical or tapered bottoms and be able to start material flow mechanically or pneumatically.
Loading Skips. Install protective guardrails on each side of loading skips if loading skips are one cubic yard or larger. Equip loading skips with a mechanical device to clear the skip of material.
Bull Floats. Where bull float handles may contact energized electrical conductors, establish a hazardous energy control clearance and lock out the power to those conductors.
Powered Concrete Trowels. Equip manually guided powered and rotating concrete troweling machines with a control switch or positive mechanical release device that automatically stops trowel rotation when the operator releases the equipment handle.[gview file=”http://www.usbr.gov/ssle/safety/RSHS/sec25.pdf” profile=”14″]