Theatrical Hoist Systems
Fly systems, also called theatrical rigging systems, fill the ceiling and wings of most theaters and performance venues. Fly systems are composed of cables, pulleys, counterweights, and related devices that enable stage crews to quickly, quietly, and safely hoist components such as curtains, lights, scenery, stage effects, and people.
To ensure the safety of performers and stage hands alike, PLASA recently released a new American National Standard (ANS) for powered hoist systems. ANSI E1.6-1 - 2012, Entertainment Technology - Powered Hoist Systems, establishes requirements for the design, manufacture, installation, inspection, and maintenance of powered hoist systems for lifting and suspension of loads for performance, presentation, and theatrical production. This standard does not apply to the structure to which the hoist is attached, to the attachment of loads to the load carrying device, to systems for flying people, to welded link chain hoists, nor to manually powered hoists.
PLASA (formerly the Entertainment Services and Technology Association), an ANSI-accredited standards developer and organizational member, is a non-profit trade association representing the North American entertainment technology industry. PLASA seeks to develop safe and sustainable standards that promote compatibility among equipment, products, and systems of competing manufacturers for the live entertainment equipment industry.
Shallow Post Foundations
The use of posts in creating foundations for commercial and residential buildings has been common in engineering and construction since the 1500s. Post foundation designs are found in the construction of strip malls, convenience stores, restaurants, housing, garages, office complexes, schools, churches, banks, fire stations, and many other structures.
To assist engineers in improving the quality of shallow post building foundation designs, a revised ANS has recently been published to ensure shallow post foundations withstand lateral and vertical forces acting on them. ANSI/ASAE EP486.2 - OCT2012, Shallow Post and Pier Foundation Design, contains safety factors and other provisions for allowable stress design (ASD), also known as working stress design, and for load and resistance factor design (LRFD), also known as strength design. ANSI/ASAE EP486.2 - OCT2012 also contains properties and procedures for modeling soil deformation for use in structural building frame analyses.
Developed by ANSI-accredited standards developer and organizational member the American Society of Agricultural and Biological Engineers (ASABE), the revised standard addresses numerous technical and practical considerations including in-situ determination of soil properties; prescriptive soil bearing capacity values; modeling analogs; safety factors as they relate to both ASD and LRFD design methodologies; ultimate lateral strength of foundations; minimum footing sizes for plain and reinforced footings; tests for modulus of horizontal sub grade reaction; adequacy of the uplift equation; effects of backfill material on lateral strength and stiffness; and use of dry concrete mixes.
ASABE is an educational and scientific membership organization of agricultural, food, and biological engineers seeking to develop efficient and environmentally sensitive methods of producing food, fiber, timber, and renewable energy sources.