scope:

Preface

This booklet was prepared under the direction of the Committee on Research of the American Institute of Steel Construction, Inc. as part of a series of publications on special topics related to fabricated structural steel. Its purpose is to serve as a supplemental reference to the AISC Manual of Steel Construction to assist practicing engineers engaged in building design.

This document is intended to provide guidelines for the design of braced and unbraced frames with partially restrained composite connections (PR-CCs). The design procedures and examples in this guide represent a refinement of the work presented by Ammerman and Leon7'8 and is thoroughly documented in more recent work by the authors.12,21 The design of structures utilizing PR-CCs for gravity and wind loads falls under the provisions of Section A2.2 of the LRFD Specification for Structural Design of Buildings. Design for seismic loads is allowed under Section 7.4.1 of the latest version of the NEHRP provisions.

The guide is divided into four parts. The first part is an introduction dealing with topics pertinent to partially restrained (PR) analysis and design, and discusses some of the important design choices utilized in the design procedures and examples. The second part contains detailed, concise design procedures for both braced and unbraced frames with partially restrained composite connections. The third part consists of a detailed design example for a four-story building. The design is for an unbraced frame in one principal direction and for a braced frame in the other. The fourth part contains design aids in the form of Tables and Appendices.

It is important that the reader recognize that the guide is intended to be a self-contained document and thus is longer than comparable documents dealing with similar topics. The reader is advised, on a first reading, to read Parts I and III carefully, consulting Part IV as necessary. Once the reader is familiar with the topic, he/she will only need to consult Parts II and IV in doing routine design work.

The design guidelines suggested by the authors that are outside the scope of the AISC Specification or Code do not represent an official position of the Institute and are not intended to exclude other design methods and procedures. It is recognized that the design of structures is within the scope of expertise of a competent licensed structural engineer, architect, or other licensed professional for the application of principles to a particular structure.