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aisc design guide 16 - errata - flush and extend multiple-row moment end-plate connections-

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Revision and Errata List, March 1, 2003 AISC Design Guide 16: Flush and Extended Multiple-Row Moment End-Plate Connections The following editorial corrections have been made in the First Printing, 2002. To facilitate the incorporation of these corrections, this booklet has been constructed using copies of the revised pages, with corrections noted. The user may find it convenient in some cases to hand-write a correction; in others, a cut-and-paste approach may be more efficient. 2.5.2 Design Procedure 2; Thin End-Plate and Larger Diameter Bolts: The following procedure results in a design with a rela- tively thin end-plate and larger diameter bolts. The design is governed by either the yielding of the end-plate or bolt rupture when prying action is included, requiring "thin" plate behavior. The "summary tables" refer to Tables 3-2 through 3-5 for the flush end-plate connections and Ta- bles 4-2 through 4-6 for the extended end-plate connec- tions. The design steps are: 1.) Determine the required plate thickness, (2-9) Note: This equation is derived from equating to given in the "summary tables" as follows: (2-10) 2.) Select a trial bolt diameter, and calculate the maximum prying force. For flush end-plate connections and for the interior bolts of extended end-plate connections, calculate as follows: Note that for flush connections Also, the last term in the numerator of Equation 2-14 represents the contribution of bolt shank bending in Figure 2- 1). For extended connections, also calculate based on the outer bolts as follows: If the radical in either expression for (Equations 2-11 and 2-15) is negative, combined flexural and shear yielding of the end-plate is the controlling limit state and the end-plate is not adequate for the speci- fied moment. 3.) Calculate the connection design strength for the limit state of bolt rupture with prying action as follows: For a flush connection: 11 (2-15) (2-16) (2-17) (2-18) For an extended connection: (2-19) where, distance from the Centerline of each tension bolt row to the center of the compression flange (Note: For rows that do not exist in a connection, that distance d is taken as zero), specified pretension in Table J3.7 of AISC ASD or Table J3.1 of AISC LRFD (also re- produced in Table 2-1 of this Guide). (2-11) (2-12) (2-13) (2-14) Rev. 3/1/03 Rev. 3/1/03 ³·² Rev. 3/1/03 ãíòêè î î íòêè î 41 Comparison of Results for the Two Design Procedures Design Procedure 1 End-Plate: A572 Gr 50 material t p = 9/16 in. Bolts: A325 d b = 5/8 in. Design Procedure 2 End-Plate: A572 Gr 50 material t p = 1/2 in. Bolts: A325 d b = 3/4 in. As expected, Design Procedure 1 results in a thicker end-plate and smaller diameter bolts than Design Procedure 2. Either design is acceptable. Note: A check of the design strength of the two designs using the procedure outlined in Appendix B yields the fol- lowing: Design Procedure 1: M n = 1987 k-in. (Thick plate behavior controlled by bolt rupture no prying ac- tion) Design Procedure 2: M n = 2108 k-in. (Thin plate behavior controlled by end-plate yielding) 4.2.2 Four-Bolt Extended Í tiffened Moment End- Plate Connection (Table 4-3) In this four-bolt stiffened example, the required factored moment of 1,750 k-in. and connection geometry of the four-bolt extended unstiffened connection of Example 4.2.1 is used so that the required end-plate thickness and bolt diameter can be compared. As before, the end-plate material is A572 Gr 50, the bolts are snug-tightened A325, and the connection is used in rigid frame construc- tion as assumed in the frame analysis. Both LRFD design procedures are illustrated. Geometric Design Data b p = b f = 8 in. t f = 3/8 in. g = 3 in. p f,i = 1 3/4 in. p f,o = 2 1/2 in. p ext = 5 in. h = 24 in. Calculate: r = 1.0 for extended connections d 0 = 24+2.5-(0.375/2) = 26.3125 in. h 0 = 26.5 in. d 1 = 24-0.375-1.75-(0.375/2) = 21.6875 in. h 1 = 21.875 in. d e = 5-2.5 = 2.5 in. Design Procedure 1 (Thick End-Plate and Smaller Diameter Bolts): 1.) Solve for the required bolt diameter assuming no pry- ing action, .in59.0 688.21313.269075.0 175022 , nt u reqdb dF M d Use d b = 5/8 in. 2.) Solve for the required end-plate thickness, t p,reqd , in.45.20.30.8 2 1 2 1 gbs p < d e Case 1 governs p f,i = 1.75 in. s use p f,i = 1.75 in. of0if1 of 0 if 1 p pshsph g ps h sp h b Y ,, ,, 2 1111 2 5.2 1 45.2 1 5.26 45.2 1 75.1 1 875.21 2 0.8 .in1.320 5.245.25.2645.275.1875.21 0.3 2 k6.274/90625.04/ 2 2 FdP tbt p ext p 1 d d 0 p t 1 w t g h s f, o f, i p f t h 0 h p b s d e Rev. 3/1/03 47 k9.10)5.2/75.1(6.15)/( ,, ofifio ppFF 2 2 2 3 4 p o py o p max,o tw F F a tw Q k39.8 5625.019.3 9.10 350 47.14 5625.019.3 2 2 2 3.) Calculate the connection design strength for the limit state of bolt rupture with prying action, k8.394/9075.04/ 2 2 FdP tbt )ddd)(d(T )d)(d(T)d)(dQ(P )dd)(d(T)dQ(P )d(T )d)(dQ(P)dQ(P M 3210b 20b31max,it 321b0max,ot 2b 31max,it0max,ot q 2 22 22 2 22 max k9.278.397.07.0 tb PT , or from Table J3.1, Use T b = 28 k .ink5539)688.28 188.31688.33313.38)(28(275.0 .ink5878)]188.31313.38)(28(2 )688.28688.33)(18.88.39(2[75.0 .ink5735 )]688.28188.31688.33)(28(2 313.38)39.88.39(2[75.0 .ink6074]188.31)28(2 688.28688.3318.88.392 313.3839.88.39275.0 max - - - - M q 4.) Check that M q > M u . If necessary, adjust the bolt di- ameter until M q is greater than M u . 46006074 q M k-in so the trial bolt, 3/4 in dia. is ok. Note: A check (not shown) of 5/8 in. bolt confirms that 3/4 in. is required. Comparison of Results for the Two Design Procedures Design Procedure 1 End-Plate: A572 Gr 50 material t p = 5/8 in. Bolts: A325 d b = ë/8 in. Design Procedure 2 End-Plate: A572 Gr 50 material t p = 9/16 in. Bolts: A325 d b = 3/4 in. As expected, Design Procedure 1 results in a thicker end-plate and smaller diameter bolts than Design Procedure 2. Either design is acceptable. Note: A check of the design strength of the two designs using the procedure outlined in Appendix B yields the fol- lowing: Design Procedure 1: M n = 5460 k-in. (Thick plate behavior controlled by bolt rupture no prying ac- tion) Design Procedure 2: M n = 5415 k-in. (Thin plate behavior controlled by end-plate yielding) 4.2.5 Multiple Row Extended Stiffened 1/3 Moment End-Plate Connection (Table 4-6) The required end-plate thickness and bolt diameter for an end-plate connection with the geometry shown below and a required factored moment of 4,600 k-in. is to be deter- mined. The end-plate material is A572 Gr 50 and the bolts are fully tightenedA325, and the connection is used in rigid frame construction as assumed in the frame analysis. Both LRFD design procedures are illustrated. Geometric Design Data b p = b f = 8 in. t f = 3/8 in. g = 3 in. Summary: t p = 9/16 in. d b = 3/4 in. p t g t w p b d p t p b f, i p f, o e b p f s s 3 h h 1 h 0 h 0 d 1 d 3 d d 2 p t ext p Rev. 3/1/03 . 3-2 through 3-5 for the flush end-plate connections and Ta- bles 4-2 through 4-6 for the extended end-plate connec- tions. The design steps are: 1.) Determine the required plate thickness, ( 2-9 ) Note:. Revision and Errata List, March 1, 2003 AISC Design Guide 16: Flush and Extended Multiple-Row Moment End-Plate Connections The following editorial corrections. controlled by end-plate yielding) 4.2.5 Multiple Row Extended Stiffened 1/3 Moment End-Plate Connection (Table 4-6 ) The required end-plate thickness and bolt diameter for an end-plate connection

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