Improved Analysis and Design of Steel Connections under Eccentric Loads

• Main Authors: Cheng-Yen Liao, 廖政彥
• Other Authors: 呂東苗
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/79983118789323840567

博士 === 國立中興大學 === 土木工程學系所 === 105 === Fillet welded joints and bolted joints are widely used in steel construction. Eccentric loading of connections is often unavoidable. Eccentric connections occur in beam-to-column connections, web splice connections of beam, and bracket supports attached to column flanges. The American Institute of Steel Construction (AISC) permits the use of elastic and instantaneous center of rotation (IC) methods to analyze eccentric loaded connections. The elastic method normally yields relatively conservative designs and the IC method, which provides more realistic analyses, is rather complex and tedious. The current AISC manual provides tables for determining coefficient C, which are used to obtain the design strength of bolt group or weld patterns. However, the tables provide values for only six angles of inclination (θ  0°, 15°, 30°, 45°, 60°, and 75°). For other angles, either a direct analysis must be performed or the values for the next lower angle increment in the tables should be used for design is recommended in the manual except straight-line interpolation. This work develops an iterative algorithm to implement a direct analysis, and proposes a rational interpolation method between C values for loads at various angles not tabulated in manual tables without the tediousness of the IC method. The proposed method is easy to implement but reasonably accurate instead of using the C values for the next lower angle increment in the tables or direct analysis. This work eliminates the current limitations on AISC design manuals. It provides a quick but reliable improvement for the analysis and design of bolted or welded groups under eccentric loads in plane.