ACI 318-08 - Seismic Requirements -- Luis E. Garcia Chapter 1 Chapter 1 Chapter 1 Chapter 1 Seismic Design Seismic Design Seismic Design Seismic Design General Requirements General Requirements Requirements Requirements in ACI 318-08 in ACI 318-08 � Modifications in � Modifications in � Scope � Scope By: By: Luis Enrique García Luis Enrique García � Terminology � Terminology President American Concrete Institute – ACI – 2008-2009 President American Concrete Institute – ACI – 2008-2009 Partner Proyectos y Diseños Ltda. Consulting Engineers Partner Proyectos y Diseños Ltda. Consulting Engineers Professor Universidad de los Andes Professor Universidad de los Andes Bogotá, Colombia Bogotá, Colombia R1.1.9 – Provisions for R1.1.9 – Provisions for R1.1.9 – Provisions for R1.1.9 – Provisions for earthquake resistance earthquake resistance earthquake resistance earthquake resistance � In this version of ACI 318 (2008), for the first � In this version of ACI 318 (2008), for the first � In this version of ACI 318 (2008), for the first � In this version of ACI 318 (2008), for the first time, earthquake resistance requirements are time, earthquake resistance requirements are � Commentary was expanded to: � Commentary was expanded to: defined defined in in function function of of the the Seismic Seismic Design Design Category — SDC required for the structure and Category — SDC required for the structure and not directly associated with the seismic risk not directly associated with the seismic risk zone. zone. � Explain changes in terminology used � Explain changes in terminology used � Simplify adoption and interaction of � Simplify adoption and interaction of � Simplify adoption and interaction of � Simplify adoption and interaction of � The minimum SDC to use is governed by the � The minimum SDC to use is governed by the ACI 318-08 with model codes and other ACI 318-08 with model codes and other legally adopted general building code of which legally adopted general building code of which documents documents ACI 318 forms a part. ACI 318 forms a part. 4 1
ACI 318-08 - Seismic Requirements -- Luis E. Garcia TABLE R1.1.9.1 — CORRELATION BETWEEN SEISMIC-RELATED Chapter 2 Chapter 2 TERMINOLOGY IN MODEL CODES Notation and Definitions Notation and Definitions Level of seismic risk or assigned seismic Code, standard, or resource performance or design categories as document and edition defined in the Code defined in the Code ACI 318-08; IBC 2000, 2003; 2006; � There were important changes in � There were important changes in NFPA 5000, 2003, 2006; ASCE 7- SCD* SCS SCD notation of the whole document and all notation of the whole document and all 98, 7-02, 7-05; NEHRP 1997, 2000, A, B C D, E, F individual Chapter notation was moved individual Chapter notation was moved 2003 to Chapter 2. to Chapter 2. BOCA National Building Code 1993, 1996, 1999; Standard SPC † SPC SPC Building Code 1994, 1997, 1999; A, B C D; E � There are a few new definitions related � There are a few new definitions related � There are a few new definitions related � There are a few new definitions related ASCE 7 93, 7 95; NEHRP 1991, ASCE 7-93, 7-95; NEHRP 1991, 1994 to Chapter 21. All definitions, old and to Chapter 21. All definitions, old and new, were moved to Chapter 2. new, were moved to Chapter 2. Uniform Building Code 1991, Seismic Zone Seismic Zone Seismic Zone 1994, 1997 0, 1 2 3, 4 * SDC = Seismic Design Category as defined in code, standard, or resource document. † SPC = Seismic Performance Category as defined in code, standard, or resource document 5 Chapter 21 Chapter 21 Seismic Design Category and Seismic Design Category and Energy Dissipation Capacity Energy Dissipation Capacity Earthquake-resistant Earthquake-resistant structures structures structures structures SDC Denomination Must comply with in Must comply with in S i Seismic Design i D i (Energy dissipation (E di i ti ACI 318-08 Category capacity) � Chapter 21 was reorganized in function of � Chapter 21 was reorganized in function of A Chapters 1 to 19 and 22 Seismic Design Categories (SDC) A, B, C, Seismic Design Categories (SDC) A, B, C, Ordinary and D, E, and F in incremental order from and D, E, and F in incremental order from ordinary to special: ordinary to special: B Chapters 1 to 19, 22, and 21.2 A → B → C → D, E, F A → B → C → D, E, F Chapters 1 to 19, 22, C Intermediate and 21.3 y 21.4 Chapters 1 to 19, 22, D, E, F Special And 21.5 to 21.13 2
ACI 318-08 - Seismic Requirements -- Luis E. Garcia ACI 318-08 – Chapter 21 ACI 318-08 – Chapter 21 21.1 – General requirements 21.1 – General requirements Earthquake-resistant structures Earthquake-resistant structures Scope Scope Content Content 21.1 – General requirements 21.1 – General requirements 21 2 21.2 – Ordinary moment frames 21.2 – Ordinary moment frames 21 2 Ordinary moment frames Ordinary moment frames B B Chapter 21 contains provisions considered Chapter 21 contains provisions considered 21.3 – Intermediate moment frames 21.3 – Intermediate moment frames C 21.4 – Intermediate precast structural walls 21.4 – Intermediate precast structural walls to be the minimum requirements for a to be the minimum requirements for a 21.5 – Flexural members of special moment frames 21.5 – Flexural members of special moment frames cast-in-place or precast concrete cast-in-place or precast concrete 21.6 – Special moment frame members subjected to bending and 21.6 – Special moment frame members subjected to bending and structure capable of sustaining a series of structure capable of sustaining a series of axial load axial load oscillations into the inelastic range of oscillations into the inelastic range of 21.7 – Joints of special moment frames 21.7 – Joints of special moment frames D response without critical deterioration in response without critical deterioration in 21.8 – Special moment frames constructed using precast concrete 21.8 – Special moment frames constructed using precast concrete strength. strength. g g 21.9 – Special structural walls and coupling beams 21.9 – Special structural walls and coupling beams E E 21.10 – Special structural walls constructed using precast 21.10 – Special structural walls constructed using precast concrete concrete F Therefore, the objective is to provide energy Therefore, the objective is to provide energy 21.11 – Structural diaphragms and trusses 21.11 – Structural diaphragms and trusses 21.12 – Foundations 21.12 – Foundations dissipation capacity in the nonlinear dissipation capacity in the nonlinear 21.13 – Members not designated as part of the seismic-force- 21.13 – Members not designated as part of the seismic-force- range of response. range of response. resisting system resisting system TABLE R21.1.1 — SECTIONS OF CHAPTER 21 TO BE SATISFIED IN TYPICAL APPLICATIONS Global Energy Dissipation Capacity Global Energy Dissipation Capacity Component resisting Seismic Design Category (SDC) earthquake effect, A B C D unless Force Force elastic elastic (none) (21.1.1.4) (21.1.1.5) (21.1.1.6) otherwise noted maximum elastic maximum elastic Maximum elastic Maximum elastic Analysis and design F e F e displacement demand displacement demand 21.1.2 21.1.2 21.1.2, 21.1.3 force demand force demand requirements requirements Materials None None 21.1.4 21.1.7 nonlinear nonlinear 21.5, 21.6, Frame members 21.2 21.3 21.7, 21.8 Maximum nonlinear Maximum nonlinear Structural walls and Yield strength Yield strength displacement demand displacement demand F y F y None None 21.9 coupling beams Precast structural walls None 21.4 21.4,† 21.10 None Structural diaphragms and None None 21.11 trusses trusses u u y u y u u e u e u u m u m Displacement Displacement Displacement Displacement Foundations None None 21.12 F u In several earthquake resistance In several earthquake resistance Frame members not = e = e R proportioned regulations this is defined through regulations this is defined through None None 21.13 to resist forces induced by F u parameter R parameter R earthquake motions y y Anclajes None 21.1.8 21.1.8 3
Recommend
More recommend
