The 2008 AISI Cold-formed Steel Design Manual

The 2008 edition of the AISI Cold-Formed Steel Design Manual has been published. The new edition includes updated examples and design aids as well as newly developed example problems and design aids covering new material in the 2007 edition of the North American Specification for the Design of Cold-Formed Steel Structural Members . Also included are all current AI SI structural Test Standards

A New AISI Cold-formed Steel Design Manual

The Specification Committee of the American Iron and Steel Institute is currently developing a new Cold Formed Steel Design Manual. The work is being done under contract with Computerized Structural Design with oversight provided by AISI Subcommittee 26 - Design Manual. This paper describes the purpose and contents of this Manual. It is expected the Manual will be published in conjunction with the new edition of the Specification for the Design of Cold-Formed Steel Structural Members early in 1997. The Manual will contain the combined versions of the Allowable Stress Design and Load and Resistance Factor Design Specifications in addition to useful new design information

The 2013 AISI Cold-Formed Steel Design Manual

The 2013 edition of the AISI Cold-Formed Steel Design Manual has been published. The new edition includes updated and newly developed example problems and design aids covering new material in the 2012 edition of the AISI North American Specification for the Design of Cold-Formed Steel Structural Members (NA Specification). Also published with the Manual are the NA Specification and the Commentary

Axial Load Capacity of Sheeted C and Z Members

An equation is developed for calculating the axial load capacity of C and Z shaped members used in roof or wall systems. The equations were determined to be valid for through fastened metal decking but not standing seam roof decking

Food choice of Antarctic soil arthropods clarified by stable isotope signatures

Antarctic soil ecosystems are amongst the most simplified on Earth and include only few soil arthropod species, generally believed to be opportunistic omnivorous feeders. Using stable isotopic analyses, we investigated the food choice of two common and widely distributed Antarctic soil arthropod species using natural abundances of 13C and 15N and an isotope labelling study. In the laboratory we fed the isotomid springtail Cryptopygus antarcticus six potential food sources (one algal species, two lichens and three mosses). Our results showed a clear preference for algae and lichens rather than mosses. These results were corroborated by field data comparing stable isotope signatures from the most dominant cryptogams and soil arthropods (C. antarcticus and the oribatid mite Alaskozetes antarcticus). Thus, for the first time in an Antarctic study, we present clear evidence that these soil arthropods show selectivity in their choice of food and have a preference for algae and lichens above mosses