2entrc6iekaecec ∑W(e-N1A)2n∑W Where plastie section modulus of beam and colu N-design axally compressive force; A-area of column section, ohal stability un Where.o-coefficient,taken as 0.9; K、N-deigherfoceanddcreuruidforoeoftclid (thn ht,depth.thickness o V.=W ( V.min:0.58-NKA1.24Mll-NAa) tue shall be checked by qu 8.2.5 Detailing requirements of members hall no be greater than th 351fm Tabke 8.3 Li yield stress of the brace 8 （2）In order to assure the plastic deformation occurs first at beam end, the following equation shall be checked. except that: 1) the columns in a storey have the shear capacities 25 percentage greater than those in the above storey, or 2) the design axially compressive force does not exceed 0.4 times of its design axial capacity, or 3) the column as an axially compressed member can keep its global stability under two times of design seismic action pc yc c pb yb å å W ( f - ³ N / ) A h W f pc yc c pb yb å å W ( f - ³ N / ) A h W f （8.6） Where: pc pb W W 、 - plastic section modulus of beam and column; N - design axially compressive force; yc yb f f 、 - yield stress of column and beam respectively; c A - area of column section; h ——Coefficient,taken as 1.15 for grade 1 frames, 1.10 for grade 2 frames and 1.05 for grade 3 frames. （3）In CBF structure, if the inversed V type or V type brace is used, the beam connecting with braces should be fabricated in a continuous member to sustain the force transferred by braces．It is checked as a simply supported beam without middle supporting under gravity load and the unbalanced load due to the buckling of one compressed brace. （4）In EBF structure, the shear capacity of link shall be checked by Equ. (8.7). This equation considers the effect of axial force in the link. w RE hile 0.15 / N A l £ £ f，V Vj g （8.7a） w ay p w f w p p min{0.58 ,2 / } ( 2 ) l l l V A f M a A h t t M W f = = - = c RE 0.15 / N A l while > £ f，V Vj g 2 c m w ay p in{0.58 1 [ /( ) ],2.4 [1 /( )]/ } Vl l = A f - - N Af M N Af a （8.7b） Where, j - coefficient, taken as 0.9; V N 、 - design shear force and design axial force of the link; c design shear capacity of the link and its modified capacity considering the influence of axial force; V N l l 、 - p full plastic moment of the link; Ml - w the length, section height, depth, thickness of web and flange of the link; a h 、 、t t 、 － w web area and the gross area of the whole section of the link; A A 、 － p W － plastic section modulus of the link; ay f f 、 － design strength and yield stress of the link; RE g － adjusting coefficient for load bearing of the link, taken as 0.85. 3、 Brace The compressed brace in CBF structure shall be checked by Equ. (8.8a) through (8.8c) br RE （8.8a） n n ay /( ) / 1/(1 0.35 ) ( / ) / N A f f E j y g y l l l p £ = + = （8.8b） Where, N － design axial force of the brace; br A － the area of the brace; j － stability coefficient for axially compressed steel members; y － reduced factor for strength considering the influence of cyclic load; n l － slenderness ratio; （8.8c） ay f － yield stress of the brace; RE g － adjusting coefficient for load bearing of the brace, taken as 0.80. E － Elastic modulus of the brace; 1、Slenderness ratio of column The slenderness ratio of columns shall not be greater than the limitation listed in Table 8.3. The table is made according to Q235 steel. For other steel, the limitation should time the factor of . ay 235/ f 8.2.5 Detailing requirements of members 120 80 60 60 Maximum slenderness ratio to the building over 12 stories 120 120 120 100 Maximum slenderness ratio to the building not exceeding 12 stories Plate element VI VII VIII IX Table 8.3 Limitation for slenderness ratio of columns