Notes to Table 4.1.8.9.:
4.1.8.11. Equivalent Static Force Procedure for Structures Satisfying the Conditions of Article 4.1.8.7. (1) The static loading due to earthquake motion shall be determined according to the procedures given in this Article. (2) Except as provided in Sentence (12), the minimum lateral earthquake force, V, shall be calculated using the following formula: V = S (Ta) MvIEW/ (RdRo) except, (a) for walls, coupled walls and wall-frame systems, V shall not be less than, S (4.0) Mv IEW/ (RdRo) (b) for moment-resisting frames, braced frames and other systems, V shall not be less than, S (2.0) Mv IEW/ (RdRo) (c) for buildings
located on a site other than Class F and having an SFRS with an Rd
equal to or greater than 1.5, V need not be greater than the larger of,  and S (0.5) IEW/ (RdRo) (3) Except as provided in Sentence (4), the fundamental lateral period, Ta, in the direction under consideration in Sentence (2) shall be determined as, (a) for moment-resisting frames that resist 100% of the required lateral forces and where the frame is not enclosed by or adjoined by more rigid elements that would tend to prevent the frame from resisting lateral forces, and where hn is in metres, (i) 0.085 (hn)3/4
for steel moment frames, (ii) 0.075 (hn)3/4
for concrete moment frames, or (iii) 0.1 N for other moment frames, (b) 0.025 hn for braced frames where hn is in metres, (c) 0.05 (hn)3/4
for shear wall and other structures where hn is in metres, or (d) other established methods of mechanics using a structural model that complies with the requirements of Sentence 4.1.8.3.(8), except that, (i) for moment-resisting frames, Ta shall not be taken greater than 1.5 times that determined in Clause (a), (ii) for braced frames, Ta
shall not be taken greater than 2.0 times that determined in Clause (b), (iii) for shear wall structures, Ta shall not be taken greater than 2.0 times that determined in Clause (c), (iv) for other structures, Ta shall not be taken greater than that determined in Clause (c), and (v) for the purpose of calculating the deflections, the period without the upper limit specified in Subclauses (d)(i) to (iv) may be used, except that, for walls, coupled walls and wall-frame systems, Ta shall not exceed 4.0 s, and for moment-resisting frames, braced frames, and other systems, Ta shall not exceed 2.0 s. (4) For single-storey buildings with steel deck or wood roof diaphragms, the fundamental lateral period, Ta, in the direction under consideration is permitted to be taken as, (a) 0.05 (hn)3/4
+ 0.004 L for shear walls, (b) 0.035 hn + 0.004 L for steel moment frames and steel braced frames, or (c) the value obtained from methods of mechanics using a structural model that complies with the requirements of Sentence 4.1.8.3.(8), except that Ta shall not be greater than 1.5 times the value determined in Clause (a) or (b), as applicable, where L is the shortest length of the diaphragm, in m, between adjacent vertical elements of the SFRS in the direction perpendicular to the direction under consideration. (5) The weight, W, of the building shall be calculated using the formula,  (6) The higher mode factor, Mv, and its associated base overturning moment reduction factor, J, shall conform to Tables 4.1.8.11.A. to 4.1.8.11.E. Table 4.1.8.11.A.   Higher Mode Factor, Mv, and Base Overturning Reduction Factor, J(1)(2)(3)(4)
for Moment-Resisting Frames Forming Part of Sentence 4.1.8.11.(6) Item   Column 1 S(0.2)/S(5.0)   Column 2 MV For Ta ≤ 0.5   Column 3 MV For Ta = 1.0   Column 4 MV For Ta = 2.0   Column 5 MV For Ta ≥5.0   Column 6 J For Ta ≤0.5   Column 7 J For Ta =1.0   Column 8 J For Ta =2.0   Column 9 J For Ta ≥5.0 

  1.   5   1   1   1   (5)   1   0.97   0.92   (5) 

  2.   20   1   1   1   (5)   1   0.93   0.85   (5) 

  3.   40   1   1   1   (5)   1   0.87   0.78   (5) 

  4.   65   1   1   1.03   (5)   1   0.80   0.70   (5)