PROPOSED CHANGE TO THE 2012 BUILDING CODE O. REG. 332/12 AS AMENDED

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1 Ministry of Municipal Affairs PROPOSED CHANGE TO THE 2012 BUILDING CODE O. REG. 332/12 AS AMENDED CHANGE NUMBER: SOURCE: B Ontario-NBC CODE REFERENCE: Division B / Division B / Division B / DESCRIPTION OF THE PROPOSED AMENDMENT This proposed change captures changes to Articles , and required as a result of an update to the seismic hazard model. EXISTING 2012 BUILDING CODE PROVISION(S) Notation (See Appendix A.) (1) In this Subsection, A r = response amplification factor to account for type of attachment of mechanical/electrical equipment, as defined in Sentence (1), A x = amplification factor at level x to account for variation of response of mechanical/electrical equipment with elevation within the building, as defined in Sentence (1), B x = ratio at level x used to determine torsional sensitivity, as defined in Sentence (9), B = maximum value of B x, as defined in Sentence (9), C p = seismic coefficient for mechanical/electrical equipment, as defined in Sentence (1), D nx = plan dimension of the building at level x perpendicular to the direction of seismic loading being considered, e x = distance measured perpendicular to the direction of earthquake loading between centre of mass and centre of rigidity at the level being considered, F a = acceleration-based site coefficient, as defined in Sentence (4), F t = portion of V to be concentrated at the top of the structure, as defined in Sentence (6), F v = velocity-based site coefficient, as defined in Sentence (4), F x = lateral force applied to level x, as defined in Sentence (6), h i, h n, h x = the height above the base (i = 0) to level i, n, or x respectively, where the base of the structure is the level at which horizontal earthquake motions are considered to be imparted to the structure, h s = interstorey height (h i - h i-1 ), I E = earthquake importance factor of the structure, as described in Sentence (1), Page 1 Copyright Queen s Printer for Ontario 2016

2 J = numerical reduction coefficient for base overturning moment, as defined in Sentence (5), J X = numerical reduction coefficient for overturning moment at level x, as defined in Sentence (7), Level i = any level in the building, i =1 for first level above the base, Level n = level that is uppermost in the main portion of the structure, Level x = level that is under design consideration, M v = factor to account for higher mode effect on base shear, as defined in Sentence (5), M x = overturning moment at level x, as defined in Sentence (7), N = total number of storeys above exterior grade to level n, N 60 = Average Standard Penetration Resistance for the top 30 m, corrected to a rod energy efficiency of 60% of the theoretical maximum, PGA = Peak Ground Acceleration expressed as a ratio to gravitational acceleration, as defined in Sentence (1), PI = plasticity index for clays, R d = ductility-related force modification factor reflecting the capability of a structure to dissipate energy through reversed cyclic inelastic behaviour, as given in Article , R o = overstrength-related force modification factor accounting for the dependable portion of reserve strength in a structure designed according to these provisions, as defined in Article , S P = horizontal force factor for part or portion of a building and its anchorage, as given in Sentence (1), S(T) = design spectral response acceleration, expressed as a ratio to gravitational acceleration, for a period of T, as defined in Sentence (7), S a (T) = 5% damped spectral response acceleration, expressed as a ratio to gravitational acceleration, for a period of T, as defined in Sentence (1), SFRS = Seismic Force Resisting System(s) is that part of the structural system that has been considered in the design to provide the required resistance to the earthquake forces and effects defined in Subsection , S u = average undrained shear strength in the top 30 m of soil, T = period in seconds, T a = fundamental lateral period of vibration of the building or structure in seconds in the direction under consideration, as defined in Sentence (3), T x = floor torque at level x, as defined in Sentence (10), V = lateral earthquake design force at the base of the structure, as determined by Article , V d = lateral earthquake design force at the base of the structure, as determined by Article , V e = lateral earthquake elastic force at the base of the structure, as determined by Article , V ed = lateral earthquake design elastic force at the base of the structure, as determined by Article , V P = lateral force on a part of the structure, as determined by Article , V s = average shear wave velocity in the top 30 m of soil or rock, W = dead load, as defined in Article , except that the minimum partition load as defined in Sentence (3) need not exceed 0.5 kpa, plus 25% of the design snow load specified in Subsection , plus 60% of the storage load for areas used for storage, except that storage garages need not be considered storage areas, and the full contents of any tanks, W i, W x = portion of W that is located at or is assigned to level i or x respectively, Copyright Queen s Printer for Ontario 2015 Page 2

3 W P = weight of a part or portion of a structure, e.g., cladding, partitions and appendages, δ ave = average displacement of the structure at level x, as defined in Sentence (9), and δ max = maximum displacement of the structure at level x, as defined in Sentence (9) Site Properties (1) The peak ground acceleration (PGA) and the 5% damped spectral response acceleration values, S a (T), for the reference ground conditions ( C in Table A.) for periods T of 0.2 s, 0.5 s, 1.0 s, and 2.0 s, shall be determined in accordance with Subsection and are based on a 2% probability of exceedance in 50 years. (2) Site classifications for ground shall conform to Table A. and shall be determined using Vs except as provided in Sentence (3). (3) If average shear wave velocity, V s, is not known, shall be determined from energy-corrected Average Standard Penetration Resistance, N 60, or from soil average undrained shear strength, s u, as noted in Table A., N60 and s u being calculated based on rational analysis. (See Appendix A.) (4) Acceleration- and velocity-based site coefficients, F a and F v, shall conform to Tables B. and C. using linear interpolation for intermediate values of S a (0.2) and S a (1.0). (5) Site-specific evaluation is required to determine F a and F v for F. (6) For structures with a fundamental period of vibration equal to or less than 0.5 s that are built on liquefiable soils, and the corresponding values of F a and F v may be determined as described in Tables A., B., and C. by assuming that the soils are not liquefiable. Copyright Queen s Printer for Ontario 2015 Page 3

4 Ground Profile Name Table A. ification for Seismic Site Response Forming Part of Sentences (1) to (3) Average Shear Wave Velocity, V (m/s) s Average Properties in Top 30 m Average Standard Penetration Soil Undrained Shear Strength, Resistance, N 60 su A Hard rock (1)(2) V s > 1500 N/A N/A B Rock (1) 760 < V s 1500 N/A N/A C Very dense soil and soft rock 360 < V s < 760 N 60 > 50 su > 100 kpa D Stiff soil 180 < V s < N kpa < su 100 kpa V s < 180 N 60 < 15 su < 50 kpa Any profile with more than 3 m of soil with the following characteristics: E Soft soil plasticity index: PI > 20 moisture content w 40%, and undrained shear strength: su < 25 kpa F Other soils (3) Site-specific evaluation required Column Notes to Table A.: (1) es A and B, hard rock and rock, are not to be used if there is more than 3 m of softer materials between the rock and the underside of footing or mat foundations. The appropriate for such cases is determined on the basis of the average properties of the total thickness of the softer materials. (See Appendix A.) (2) If V s has been measured in-situ, the Fa and Fv values derived from Tables B. and C. may be multiplied by (1500 / V s ) 1/2. (3) Other soils include: (a) liquefiable soils, quick and highly sensitive clays, collapsible weakly cemented soils, and other soils susceptible to failure or collapse under seismic loading, (b) peat and/or highly organic clays greater than 3 m in thickness, (c) highly plastic clays (PI > 75) more than 8 m thick, and (d) soft to medium stiff clays more than 30 m thick. Table B. Values of Fa as a Function of and Sa(0.2) Forming Part of Sentence (4) Values of Fa Sa(0.2) 0.25 Sa(0.2) = 0.5 Sa(0.2) = 0.75 Sa(0.2) = 1.00 Sa(0.2) 1.25 A B C D E F (1) (1) (1) (1) (1) Column Notes to Table B.: (1) See Sentence (5). Copyright Queen s Printer for Ontario 2015 Page 4

5 Table C. Values of Fv as a Function of and Sa(1.0) Forming Part of Sentence (4) Values of Fv Sa(1.0) 0.1 Sa(1.0) = 0.2 Sa(1.0) = 0.3 Sa(1.0) = 0.4 Sa(1.0) 0.5 A B C D E F (1) (1) (1) (1) (1) Column Notes to Table C.: (1) See Sentence (5). (7) The design spectral acceleration values of S(T) shall be determined as follows, using linear interpolation for intermediate values of T: S(T) = F a S a (0.2) for T 0.2 s = F v S a (0.5) or F a S a (0.2), whichever is smaller for T = 0.5 s = F v S a (1.0) for T = 1.0 s = F v S a (2.0) for T = 2.0 s = F v S a (2.0) / 2 for T 4.0 s Elements of Structures, Non-Structural Components and Equipment (See Appendix A.) (1) Except as provided in Sentences (2) and (8), elements and components of buildings described in Table and their connections to the structure shall be designed to accommodate the building deflections calculated in accordance with Article and the element or component deflections calculated in accordance with Sentence (10), and shall be designed for a lateral force, V P, applied through the centre of mass of the element or component that is equal to: where, F a = as defined in Table B., V p = 0.3F a S a (0.2) I E S p W p S a (0.2) = spectral response acceleration value at 0.2 s, as defined in Sentence (1), I E = importance factor for the building, as defined in Article , S p = C p A r A x /R p (the maximum value of S p shall be taken as 4.0 and the minimum value of S p shall be taken as 0.7), where, C p = element or component factor from Table , A r = element or component force amplification factor from Table , A x = height factor (1 + 2 h x / h n ), R p = element or component response modification factor from Table , and W p = weight of the component or element. Copyright Queen s Printer for Ontario 2015 Page 5

6 PROPOSED CODE CHANGE Revise existing Articles , and as follows: Notation (See Appendix A.) (1) In this Subsection, A r = response amplification factor to account for type of attachment of mechanical/electrical equipment, as defined in Sentence (1), A x = amplification factor at level x to account for variation of response of mechanical/electrical equipment with elevation within the building, as defined in Sentence (1), B x = ratio at level x used to determine torsional sensitivity, as defined in Sentence (9), B = maximum value of B x, as defined in Sentence (9), C p = seismic coefficient for mechanical/electrical equipment, as defined in Sentence (1), D nx = plan dimension of the building at level x perpendicular to the direction of seismic loading being considered, e x = distance measured perpendicular to the direction of earthquake loading between centre of mass and centre of rigidity at the level being considered (See Appendix A), F a = acceleration-based site coefficient for application in Subsection , as defined in Sentence (4)Sentence (7), F(PGA) = site coefficient for PGA, as defined in Sentence (5), F(PGV) = site coefficient for PGV, as defined in Sentence (5), F s = site coefficient as defined in Sentence (2) for application in Article F(T) = site coefficient for spectral acceleration, as defined in Sentence (5), F t = portion of V to be concentrated at the top of the structure, as defined in Sentence (6), F v = velocity-based site coefficient for application in Subsection , as defined in Sentence (4) (7), F x = lateral force applied to level x, as defined in Sentence (6), h i, h n, h x = the height above the base (i = 0) to level i, n, or x respectively, where the base of the structure is the level at which horizontal earthquake motions are considered to be imparted to the structure, h s = interstorey height (h i - h i-1 ), I E = earthquake importance factor of the structure, as described in Sentence (1), J = numerical reduction coefficient for base overturning moment, as defined in Sentence (5), J X = numerical reduction coefficient for overturning moment at level x, as defined in Sentence (7), Level i = any level in the building, i =1 for first level above the base, Level n = level that is uppermost in the main portion of the structure, Level x = level that is under design consideration, M v = factor to account for higher mode effect on base shear, as defined in Sentence (5), M x = overturning moment at level x, as defined in Sentence (7), N = total number of storeys above exterior grade to level n, Copyright Queen s Printer for Ontario 2015 Page 6

7 N 60 = Average Standard Penetration Resistance for the top 30 m, corrected to a rod energy efficiency of 60% of the theoretical maximum, PGA = Peak Ground Acceleration expressed as a ratio to gravitational acceleration, as defined in Sentence (1), PGA ref = reference PGA for determining F(T), F(PGA) and F(PGV), as defined in Sentence (4), PGV = Peak Ground Velocity, in m/s, as defined in Sentence (1), PI = plasticity index for clays, R d = ductility-related force modification factor reflecting the capability of a structure to dissipate energy through reversed cyclic inelastic behaviour, as given in Article , R o = overstrength-related force modification factor accounting for the dependable portion of reserve strength in a structure designed according to these provisions, as defined in Article , R s = combined overstrength and ductility-related modification factor, as defined in Sentence (7), for application in Article , S P = horizontal force factor for part or portion of a building and its anchorage, as given in Sentence (1), S(T) = design spectral response acceleration, expressed as a ratio to gravitational acceleration, for a period of T, as defined in Sentence (7), S a (T) = 5% damped spectral response acceleration, expressed as a ratio to gravitational acceleration, for a period of T, as defined in Sentence (1), SFRS = Seismic Force Resisting System(s) is that part of the structural system that has been considered in the design to provide the required resistance to the earthquake forces and effects defined in Subsection , S u = average undrained shear strength in the top 30 m of soil, T = period in seconds, T a = fundamental lateral period of vibration of the building or structure in seconds in the direction under consideration, as defined in Sentence (3), T x = floor torque at level x, as defined in Sentence (10), V = lateral earthquake design force at the base of the structure, as determined by Article , V d = lateral earthquake design force at the base of the structure, as determined by Article , V e = lateral earthquake elastic force at the base of the structure, as determined by Article , V ed = lateral earthquake design elastic force at the base of the structure, as determined by Article , V P = lateral force on a part of the structure, as determined by Article , V s = lateral earthquake design force at the base of the structure, as determined by Sentence (7), for application in Article , V s30 = average shear wave velocity in the top 30 m of soil or rock, W = dead load, as defined in Article , except that the minimum partition load as defined in Sentence (3) need not exceed 0.5 kpa, plus 25% of the design snow load specified in Subsection , plus 60% of the storage load for areas used for storage, except that storage garages need not be considered storage areas, and the full contents of any tanks (See Appendix A), W i, W x = portion of W that is located at or is assigned to level i or x respectively, W P = weight of a part or portion of a structure, e.g., cladding, partitions and appendages, Copyright Queen s Printer for Ontario 2015 Page 7

8 W t = sum of W i over the height of the building, for application in Sentence (7), δ ave = average displacement of the structure at level x, as defined in Sentence (9), and δ max = maximum displacement of the structure at level x, as defined in Sentence (9) Site Properties (1) The peak ground acceleration (PGA), peak ground velocity (PGV), and the 5% damped spectral response acceleration values, S a (T), for the reference ground conditions ( C in Table A.) for periods T of 0.2 s, 0.5 s, 1.0 s, and 2.0 s, 5.0 s and 10.0 s shall be determined in accordance with Subsection and are based on a 2% probability of exceedance in 50 years. Table A. ification for Seismic Site Response Forming Part of Sentences (1) to (3) Ground Profile Name Average Shear Wave Velocity, V s30 (m/s) Average Properties in Top 30 m Average Standard Penetration Resistance, N 60 Soil Undrained Shear Strength, su A Hard rock (1)(2) V s30 > 1500 N/A N/A B Rock (1) 760 < V s N/A N/A C Very dense soil and soft rock 360 < V s30 < 760 N 60 > 50 su > 100 kpa D Stiff soil 180 < V s30 < N kpa < su 100 kpa V s30 < 180 N 60 < 15 su < 50 kpa E Soft soil Any profile with more than 3 m of soil with the following characteristics: plasticity index: PI > 20 moisture content w 40%, and undrained shear strength: su < 25 kpa F Other soils (3) Site-specific evaluation required Column Notes to Table A.: (1) es A and B, hard rock and rock, are not to be used if there is more than 3 m of softer materials between the rock and the underside of footing or mat foundations. The appropriate for such cases is determined on the basis of the average properties of the total thickness of the softer materials. (See Appendix A.) (2) If Where V s30 has been measured in-situ, the Fa and Fv the F(T) values for A derived from Tables B. to G are permitted to be multiplied and C. may be multiplied by the factor 0.04+(1500 / V s30 ) 1/2. (3) Other soils include: (a) liquefiable soils, quick and highly sensitive clays, collapsible weakly cemented soils, and other soils susceptible to failure or collapse under seismic loading, (b) peat and/or highly organic clays greater than 3 m in thickness, (c) highly plastic clays (PI > 75) more than 8 m thick, and (d) soft to medium stiff clays more than 30 m thick. Copyright Queen s Printer for Ontario 2015 Page 8

9 (2) Site classifications for ground shall conform to Table A. and shall be determined using V s30 provided in, or where V s30 is not known, using Sentence (3). except as (3) If average shear wave velocity, V s30, is not known, shall be determined from energy-corrected Average Standard Penetration Resistance, N 60, or from soil average undrained shear strength, s u, as noted in Table A., N60 and s u being calculated based on rational analysis. (See Appendix A.) (4) For the purpose of determining the values of F(T) to be used in the calculation of design spectral acceleration, S(T), in Sentence (9), and the values of F(PGA) and F(PGV), the value of PGA ref to be used with Tables B. to I. shall be taken as (a) 0.8 PGA where the ratio S a (0.2)/PGA < 2.0, and (b) 1 PGA otherwise. (45) The values of the site coefficient for design spectral acceleration at period T, F(T), and of similar coefficients F(PGA) and F(PGV), Acceleration- and velocity-based site coefficients, F a and F v, shall conform to Tables B. and C.to I. using linear interpolation for intermediate values of PGA ref S a (0.2) and S a (1.0). Table B. Values of FaF(0.2) as a Function of and Sa(0.2)PGAref Forming Part of Sentence (4) and (5) Sa(0.2) 0.25 PGAref 0.1 Sa(0.2) = 0.5 PGAref = 0.2 Values of Fa(0.2) Sa(0.2) = 0.75 PGAref = 0.3 Sa(0.2) = 1.00 PGAref = 0.4 Sa(0.2) 1.25 PGAref 0.5 A B C D E F (1) (1) (1) (1) (1) Column Notes to Table B.: (1) See Sentence (5).Sentence (6) Copyright Queen s Printer for Ontario 2015 Page 9

10 Table C. Values of Fv(0.5) as a Function of and Sa(1.0)PGAref Forming Part of Sentence (4) and (5) Sa(1.0) 0.1 PGAref 0.1 Sa(1.0) = 0.2 PGAref = 0.2 Values of F(0.5)v Sa(1.0) = 0.3 PGAref = 0.3 Sa(1.0) = 0.4 PGAref = 0.4 Sa(1.0) 0.5 PGAref 0.5 A B C D E F (1) (1) (1) (1) (1) Column Notes to Table C.: (1) See Sentence (5).Sentence (6). Table D. Values of F(1.0) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(1.0) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table D.: (1) See Sentence (6). Copyright Queen s Printer for Ontario 2015 Page 10

11 Table E. Values of F(2.0) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(2.0) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table E.: (1) See Sentence (6). Table F. Values of F(5.0) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(5.0) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table F.: (1) See Sentence (6). Copyright Queen s Printer for Ontario 2015 Page 11

12 Table G. Values of F(10.0) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(10.0) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table G.: (1) See Sentence (6). Table H. Values of F(PGA) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(PGA) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table H.: (1) See Sentence (6). Copyright Queen s Printer for Ontario 2015 Page 12

13 Table I. Values of F(PGV) as a Function of and PGA ref Forming part of Sentence (4) and (5) Values of F(PGV) PGA ref 0.1 PGA ref = 0.2 PGA ref = 0.3 PGA ref = 0.4 PGA ref 0.5 A B C D E F (1) (1) (1) (1) (1) Note to Table I.: (1) See Sentence (6). (56) Site-specific evaluation is required to determine F a and F(T) v, F(PGA) and F(PGV) for F. (7) For all applications in Subsection , F a = F(0.2) and F v = F(1.0). (68) For structures with a fundamental period of vibration equal to or less than 0.5 s that are built on liquefiable soils, and the corresponding values of F(T) a and F v may be determined as described in Tables A., B., and C. by assuming that the soils are not liquefiable. (79) The design spectral acceleration values of S(T) shall be determined as follows, using linear interpolation for intermediate values of T: S(T) = F(0.2) a S a (0.2) or F(0.5)S a (0.5), whichever is larger for T 0.2 s = F(0.5) v S a (0.5) or F a S a (0.2), whichever is smaller for T = 0.5 s = F(1.0) v S a (1.0) for T = 1.0 s = F(2.0) v S a (2.0) for T = 2.0 s = F(5.0) v S a (5.0)(2.0)/2 for T 4.0= 5.0 s = F(10.0)S a (10.0) for T 10.0 S Copyright Queen s Printer for Ontario 2015 Page 13

14 Elements of Structures, Non-Structural Components and Equipment (See Appendix A.) (1) Except as provided in Sentences (2) and (8), elements and components of buildings described in Table and their connections to the structure shall be designed to accommodate the building deflections calculated in accordance with Article and the element or component deflections calculated in accordance with Sentence (10), and shall be designed for a lateral force, V P, applied through the centre of mass of the element or component that is equal to: where, V p = 0.3F a S a (0.2) I E S p W p F a = as defined in Sentence (7)Table B., S a (0.2) = spectral response acceleration value at 0.2 s, as defined in Sentence (1), I E = importance factor for the building, as defined in Article , S p = C p A r A x /R p (the maximum value of S p shall be taken as 4.0 and the minimum value of S p shall be taken as 0.7), where, C p = element or component factor from Table , A r = element or component force amplification factor from Table , A x = height factor (1 + 2 h x / h n ), R p = element or component response modification factor from Table , and W p = weight of the component or element. RATIONALE FOR CHANGE Problem/General Background A major update of seismic hazard model in Canada has been undertaken to incorporate current knowledge on the subject and alignment with modern seismic hazard maps used in building codes in the United States and other jurisdictions. The update of seismic model involves incorporation of new GMPE (Ground Motion Prediction Equations) for most locations in Canada, inclusion of Cascadia subduction source probabilistically to seismic hazard for areas of western Canada and the explicit inclusion of fault sources such as those in Haida Gwaii and the Yukon. Some provisions in Article and are not aligned with the new seismic hazard model and need to be revised. Justification/Explanation This proposed change would harmonize requirements with the model National Building Code of Canada. The major changes required as a result of adoption of new hazard values are as follows: Article : Notation for terms F(T), F(PGA),F(PGV), PGA ref, PGV added as these are new terms introduced in the Building Code, Notation for Fa and Fv revised to align with the changes proposed in the Building Code Sentence (1) Spectral acceleration values for 5 and 10 s have been added in subsection on the Building Code, Peak Ground Velocity ( PGV) has also been added. Copyright Queen s Printer for Ontario 2015 Page 14

15 Sentence (4) The attenuation of ground motion in Eastern Canada is less than in the West. The direct use of PGA would give F(T) values with larger non-linear de-amplification effects in the east than is appropriate for their sustained level of shaking. This would be unconservative and thus have potential safety implications. Consequently an adjustment factor is needed to provide for appropriate foundation factors at eastern sites Sentence (5) A much expanded database of ground motion recordings in earthquakes, since the current Fa and Fv factors were established, allows determination of site amplifications at a wide range of horizontal periods of vibration, which have been incorporated into modern Ground Motion Prediction Equations. Accordingly, period dependant foundation factors and foundation factors for PGA and PGV have been proposed. Sentence (6) Editorial revision to coordinate shift from Fa and Fv to F(T), F(PGA) and F(PGV) Sentence (7) Definition of Fa and Fv in terms of F(T) to coordinate with other provisions in Article as triggers and other formulae in Article are currently using Fa and Fv instead of F(T). Sentence (8) Editorial revision to coordinate with shift from Fa and Fv to F(T) Sentence (9) Formulae for Design Spectral response acceleration are now expressed in terms of F(T) to incorporate use of period based foundation factors. The values for design spectral response at 5 and 10 seconds have been added. For some localities, S(0.5) is larger than S(0.2). Considering that it is not a good practice to design on the basis of a spectrum in which the S value increases with period, the design spectral acceleration expression has been modified. Article : Editorial revision to correct reference for Fa Cost/Benefit Implications In some location the assessed hazard has gone up and in other areas it has gone down. There may be cost increases or decreases wherever the estimated hazard has changed. In many localities in eastern Canada the estimated hazard has decreased, which will result in cost savings.. There may be cost increase or decrease of the order of 1% of the overall cost of the building wherever the estimated hazard has changed. Enforcement Implications None Who is Affected Building officials, Consultants, builders and Building Owners. Copyright Queen s Printer for Ontario 2015 Page 15

16 Objective Based Analysis Provision Objective/Functional Statement Division B (1) Division B (1) 1 [F20-OS2.1] (1) 1 [F20-OP2.1][F22-OP2.4] (2) 2 [F20-OS2.1] (2) 2 [F20-OP2.1][F22-OP2.4] (3) 3 (4) [F20-OS2.1] (4) [F20-OP2.1][F22-OP2.4] (5) 4 [F20-OS2.1] (5) 4 [F20-OP2.1][F22-OP2.4] (6) 5 [F20-OS2.1] (6) 5 [F20-OP2.1][F22-OP2.4] (7) (8) 6 (9) 7 [F20-OS2.1] (9) 7 [F20-OP2.1][F22-OP2.4] Copyright Queen s Printer for Ontario 2015 Page 16

17 Provision Objective/Functional Statement Division B (1) [F20, F22-OP2.3] [F22-OP2.4] (1) [F20, F22-OS2.4] OTHER SUPPORTING MATERIALS Copyright Queen s Printer for Ontario 2015 Page 17