外文翻译--冷弯型钢框架结构设计方法.doc

PRESCRIPTIVE METHOD FOR RESIDENTIAL COLD-FORMED STEEL FRAMING Second Edition Prepared for The U.S. Department of Housing and Urban Development Office of Policy Development and Research Washington, DC Co-Sponsored by The American Iron and Steel Institute Washington, DC and The National Association of Home Builders Washington, DC by NAHB Research Center, Inc. 400 Prince Georges Boulevard Upper Marlboro, MD 20774-8731 August 1997 CONTENTS 5.0 STEEL FLOOR FRAMING 21 5.1 Floor Construction 21 5.2 Floor to Foundation or Bearing Wall Connection 21 5.3 Allowable Joist Spans 21 5.4 Joist Bracing 21 5.5 Floor Cantilevers 22 5.6 Splicing 22 5.7 Framing of Floor Openings 22 5.8 Floor Trusses 22 5.0 STEEL FLOOR FRAMING 5.1 Floor Construction Cold-formed steel framing members shall comply with the provisions of Section 2.0. Steel floors shall be constructed in accordance with this section and Figure 5.1. 5.1.1 Applicability Limits The applicability limits of Section 1.3 and Table 1.1 shall apply. 5.1.2 In-Line Framing. Load bearing steel floor framing, wall framing, and ceiling/roof framing shall be constructed in-line with the vertical load bearing members (i.e. studs) located below. A maximum tolerance of 3/4 inch (19 mm) between the centerlines of the in-line members shall be permitted in accordance with Figure 1.2. 5.2 Floor to Foundation or Bearing Wall Connection Cold-formed steel floor framing shall be anchored to foundations, wood sills, or load bearing walls in accordance with Table 5.1 and Figures 5.1 through 5.10. Fastening of steel joists to other framing members shall be in accordance with Table 5.2. 5.3 Allowable Joist Spans The clear span of cold-formed steel floor joists shall not exceed the limits set forth in Table 5.3 for single spans and Table 5.4 for multiple spans. When continuous joist members are used for multiple spans, the interior bearing supports shall be located within two feet (0.6 m) of mid-span of the steel joists, and the