AISC curtis pdf free download
AISC curtis pdf free download.Column Flange Strength at Moment End-Plate Connections.
Current American Institute of Steel Construction (AISC) design recommendations for moment end-plate connections are basically limited to the end-plate, bolts, and the compression region of the column side of the connection (AISC 2,3.4 ). Although specific design procedures for column flange strength at the tension regions of the connection have not been included in AISC design manuals, much research on this topic has been conducted in Europe (Zoetemeijer, 16 Packer and Morris, 15 Mann and Morris, 12 Kennedy, Vinnakota, and Sherbourne, 8 ) and in the United States. 4,7 (See Murray, Ref. 13, for a more complete list.) The purpose of this paper is to present design recommendations for required column flange strength at the tension region of the moment end-plate connection configurations shown in Figs. 1 and 2. The configuration shown in Fig. 1 will be referred to as the 4-bolt stiffened end-plate and that in Fig. 2 as the 8-bolt stiffened end-plate. A design procedure for the latter configuration has recently been published. Limit states associated with the column flange at moment end-plate connections include column flange flexural strength, connection stiffness, and the effect on tension bolt forces because of flange bending. Criteria to evaluate these limit states have typically been developed using a tee-stub analogy. In this analogy, a prescribed effective column flange length is used for the length of the tee-stub flange as shown in Fig. 3. Procedures utilizing yield-line theory and finite element analysis have been used to analyze this teestub model. Yield-line based studies were performed by Zoetemeijer; 16 Packer and Morris; 15 Mann and Morris; 12 and Kennedy, Vinnakota, and Sherbourne, 8 among others. All these studies utilize the concept of an effective column flange length and an assumed yield-line pattern over this length. The first three studies develop design methods based on experimentally tested beam-to-column moment end-plate connections. The latter study utilizes two tee-stub tests to justify the results. Finite element studies, have been performed by Krish- namurthy, 9,10 Ahuja, 2 and Ghassemich. 6 The first studies resulted in design procedure for 4-bolt, stiffened end-plates (Fig. 1). The latter two studies used the tee-stub analogy to develop design procedures for the 8-bolt stiffened, end-plate configuration shown in Fig. 2. All of these studies resulted in design equations for end-plate strength that were developed using regression analyses techniques and finite element analysis results. The latter two studies also provide regression analysis based equations for predicting end-plate stiffness and bolt force including prying effects. Although these procedures are for end-plate design, they can be adapted for the design of the column flange in the tension region of a beam-to-column moment end-plate connection if an effective column flange length is defined. Hendrick and Murry 7 conducted a limited series of tests to evaluate several European design methods for use with North American rolled sections. They concluded that the method proposed by Man and Morris 12 is the most suitable for the evaluation of unstiffened column flanges in the tension region of 4-bolt, unstiffened end-plate connections. They also modified the Krishnamurthy 10 results by introducing an effective column flange length equal to 3.5 times the vertical bolt pitch at the beam tension flange to obtain the same results as found with the Mann and Morris 12 equations. Finally, they developed a “rule of thumb,” found in the AISC Engineering for Steel Construction, 3 which states that, under certain limitations, the column flange is adequate if its thickness is greater than the required bolt diameter from the Krishnamurthy end-plate design procedure.AISC curtis pdf download.
