Pp_ Asep Midas_ Intro To Perf-based Design Rev2018 0928 2s.pdf

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NON-LINEAR TIME HISTORY ANALYSIS (NLTHA) OF TALL BUILDINGS

Introduction to Performance-Based Design

Acknowledgements

Introduction to Performance-Based Design

Special thanks to the following who are the sources of this presentation materials:

❑Dr. Naveed Anwar ❑Engr. Thaung Htut Aung

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design Estimating Stiffness through “Cracking Modifiers” ❑

❑

Code specified cracking factors / modifiers ❑

Typical to all members;

❑

At all locations; and

❑

For all load cases.

Not realistic and subject to considerable variation and “debate/discussion”

Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

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Dynamic Response of Tall Buildings

Introduction to Performance-Based Design

Modal Dynamic Response

Introduction to Performance-Based Design

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Modal Dynamic Response

Introduction to Performance-Based Design Modal Analysis ❑ The modal analysis determines the inherent natural frequencies of vibration. ❑ Each natural frequency is related to a time period and a mode shape. ❑ Time period is the time it takes to complete a complete one cycle of vibration. ❑ The mode shape is a normalized deformation pattern. ❑ The number of modes is typically equal to the number of degrees of freedom (DOF). ❑ The time period and mode shapes are inherent properties of the structure and do not depend on the applied loads.

Modal Dynamic Response

Introduction to Performance-Based Design

Natural Structure Period (or Frequency) ❑ The heartbeat of the structure. ❑ Indicates the stiffness and mass relationship. ❑ Basis for damping, resonance and amplification effects. ❑ Indicates relationship for tall buildings such as 0.1𝑁, with height as 𝐶𝑡 ℎ𝑛 0.75 , etc.

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Modal Dynamic Response

Introduction to Performance-Based Design

Estimating Natural Structure Period (or Frequency) ❑ Use non-linear models. ❑ Apply gravity loads incrementally as a non-linear case. ❑ Determine modal properties at the end of the gravity load case. ❑ Use gravity load case and modal properties as a start for other cases.

Modal Dynamic Response

Introduction to Performance-Based Design

Mode Shapes ❑ A mode shape is a set of relative (not absolute) modal displacement for a particular mode of free vibration for a specific natural frequency. ❑ There are as many modes as there are DOFs in the system. ❑ Not all of the modes are significant. ❑ Local modes may disrupt the modal mass participation.

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Introduction to Performance-Based Design

Modal Dynamic Response

Why Modal Analysis ❑

The modal analysis should be run first before applying loads of any other analysis to check the model and to understand the response of the structure.

❑

Modal analysis is precursor to most types of analysis including Response Spectrum, Time-History, Pushover analysis, etc.

❑

Modal analysis is a useful tool even if full dynamic analysis is not performed.

❑

Modal analysis is easy to run and is fun to watch when animated.

Introduction to Performance-Based Design

Modal Dynamic Response

Application of Modal Analysis ❑

The time period and mode shapes, together with animation immediately exhibit the strengths and weaknesses of the structure.

❑

Modal analysis can be used to check the accuracy of the structural model. ❑

The time period should be within the reasonable range;

❑

The disconnected members can be easily identified; and

❑

Local modes are identified that may need suppression.

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Introduction to Performance-Based Design Application of Modal Analysis

Modal Dynamic Response

❑

The symmetry of the structure can be determined. ❑

For doubly-symmetrical buildings, generally the first two modes are translational and the third mode is rotational; and

❑

For unsymmetrical buildings, If the first mode is rotational.

Introduction to Performance-Based Design Application of Modal Analysis

Modal Dynamic Response

❑

❑

The symmetry of the structure can be determined. ❑

For doubly-symmetrical buildings, generally the first two modes are translational and the third mode is rotational; and

❑

For unsymmetrical buildings, If the first mode is rotational.

The resonance with the applied loads or excitation can be avoided. ❑

The natural frequency of the structure should not be close to the frequency of excitation.

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Modal Dynamic Response

Introduction to Performance-Based Design

Modal Dynamic Response

Introduction to Performance-Based Design

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Introduction to Performance-Based Design Nonlinear Analysis P-Delta Analysis Buckling Analysis Static Pushover Analysis Fast Nonlinear Analysis (FNA) Large Displacement Analysis

Modal Dynamic Response

Special Analysis Types

Dynamic Analysis Free Vibration and Modal Analysis Response Spectrum Analysis Steady State Dynamic Analysis

Introduction to Performance-Based Design Seismic Analysis Procedures

Modal Dynamic Response

Linear Static Procedure Equivalent Static Analysis

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Nonlinear Static Procedure Capacity Spectrum Method Displacement Coefficient Method Other Pushover Analysis Methods

Nonlinear Linear Dynamic Dynamic Procedure Procedure Response Spectrum Analysis Linear Response History Analysis

Nonlinear Time History Analysis (NLTHA)

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Introduction to Performance-Based Design

Modal Dynamic Response

Advantages of Nonlinear Dynamic Time History • It applies to all types of structures. • It accounts directly for the dynamic nature of earthquake loads. • It accounts directly for hysteretic loops and energy dissipation. • It is more accurate than pushover analysis.

Introduction to Performance-Based Design

Modal Dynamic Response

Disadvantages of Nonlinear Dynamic Time History • It is more complex that needs more information, tools and skills. • Response spectrum cannot be used but ground motions. • The response can be sensitive to changes in the ground motion; that the analysis must be carried out for a number of earthquakes. • Analysis requires more computer run time that the pushover analysis.

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design APPROACH Prescriptive-based (emphasis on the procedures) Performance-based (emphasis on key performance indicators)

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PROCEDURE Specify “what and how to do?” Ex. Make concrete mix 1:2:4 Whatever it takes! (within certain bounds)

OUTCOME Implicit expectation (A strength of 50 MPa is expected) Explicit performance (Concrete less than 40 MPa is rejected)

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Progression of Structural Design Approaches

Introduction to Performance-Based Design

Progression of Structural Design Approaches

Introduction to Performance-Based Design

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Introduction to Performance-Based Design Motivation for Performance-Based Design (PBD) in earthquake Modal Dynamic Response

• Lack of explicit performance in design codes is the primary motivation for PBD. • Performance-based methods require the designer to assess how a building is likely to perform due to extreme events and their correct application to identify “unsafe” design. • Enable arbitrary restrictions to be lifted or relaxed and provides scope for the development of innovative, safer and cost-effective solutions.

Introduction to Performance-Based Design

Why PBD?

PERFORMANCE BASED-SEISMIC DESIGN ❑

To substantiate exceptions to specific prescribed code requirements.

❑

To demonstrate higher performance levels for a structure.

❑

An integral component is nonlinear response history analysis.

❑

Significantly involves more effort in the analysis and design stages.

❑

Use of seismic force-resisting systems and innovative designs that are not prescribed by code.

❑

More common in design of high-rise buildings in some parts of the world such as western US.

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Why PBD?

Introduction to Performance-Based Design

PBD Required Data

Introduction to Performance-Based Design • Description of building, structural system • Codes, standards and references • Loading criteria • Materials • Modeling, analysis and design procedures • Performance objectives and acceptance criteria

• SPT values • Soil stratification and properties • Soil type for seismic loading • Allowable bearing capacity • Sub-grade modulus • Liquefaction potential • Basement wall pressure

• Earthquake hazard determination • Ground motion characterizations • Recommended spectra (SLE, DBE, and MCE)

• 10-year return period wind load • 50-year or 700-year return period wind load • Floor accelerations (1-year, 5-year return periods) • Rotational velocity (1-year return period) • Natural frequency sensitivity study

Basis of design

Geotechnical investigation

Site-specific PSHA

Wind tunnel test

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• Geotechnical investigation • Probabilistic seismic hazard assessment

Introduction to Performance-Based Design

PBD Procedure

Preliminary design

Wind tunnel test

Detailed codebased design

SLE Evaluation

MCE Evaluation

Peer review

Introduction to Performance-Based Design

PBD Procedure: Preliminary Design

Structural system development

• Bearing wall system • Dual system • Special moment resisting frame • Intermediate moment resisting frame

Finite element modeling • Linear analysis models • Different stiffness assumptions for seismic and wind loadings

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Check overall response • Modal analysis • Natural period, mode shapes, modal participating mass ratios • Gravity load response • Building weight per floor area • Deflections • Lateral load response (DBE, Wind) • Base shear, story drift, displacement

Preliminary member sizing

• Structural density ratios • Slab thickness • Shear wall thickness • Coupling beam sizes • Column sizes

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• Apply wind loads from wind tunnel test in mathematical model • Ultimate strength design • 50-year return period wind load x Load factor • 700-year return period wind load • Serviceability check • Story drift ≤ 0.4%, Lateral displacement ≤ H/400 (10-year return period wind load) • Floor acceleration (1-year and 5-year return period wind load)

Seismic design

• Either nominal or expected material properties are used based on strength and service level design • Different cracked section properties for wind and seismic models • P-delta effects • Rigid zones and endlength offsets

Wind design

Modeling

PBD Procedure

Introduction to Performance-Based Design

• Use recommended design spectrum of DBE from PSHA • Apply seismic load in principal directions of the building • Scaling of base shear from response spectrum analysis • Consider accidental torsion, directional and orthogonal effects • 5% of critical damping is used for un-modeled energy dissipation • Design and detail reinforcement

Introduction to Performance-Based Design PBD Procedure: Seismic Performance Objectives

Level of Earthquake

Seismic Performance Objective

Service Level Earthquake Serviceability: Structure to remain essentially elastic with minor (SLE): 50% probability of yielding of structural elements, minor cracking of concrete, and exceedance in 30 years (43- minor damage to non-structural elements. year return period), 2.5% of structural damping Maximum Considered Earthquake (MCE): 2% probability of exceedance in 50 years (2475-year return period)

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Collapse Prevention: Structure has a low probability of collapse which will be demonstrated implicitly through analyses that indicate the structure has stable, predictable response to MCE R shaking at response levels which do not result in loss of gravity load carrying capacity or substantial degradation of lateral resistance. Extensive structural damage may occur; repairs to structural and non-structural systems are required and may not be economically feasible.

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PBD Procedure: Expected Material Strength

Introduction to Performance-Based Design

PBD Procedure: Expected Material Strength

Introduction to Performance-Based Design Component Structural walls (inplane) Structural walls (outof-plane) Basement walls (inplane) Basement walls (outof-plane) Coupling beams (Diagonal-reinforced) Coupling beams (Conventionalreinforced)

SLE/Wind (Strength) SLE/Wind (Service) Flexural – 0.75 EcIg Flexural – 1.0 EcIg

DBE Flexural – 0.6 EcIg

MCE Flexural – **

Shear – 1.0 GcAg Flexural – 0.25 EcIg

Shear – 1.0 GcAg Flexural – 1.0 EcIg

Shear – 1.0 GcAg Flexural – 0.25 EcIg

Shear – 0.2 GcAg Flexural – 0.25 EcIg

Flexural – 1.0 EcIg

Flexural – 1.0 EcIg

Flexural – 1.0 EcIg

Flexural – 0.8 EcIg

Shear – 1.0 GcAg Flexural – 0.25 EcIg

Shear – 1.0 GcAg Flexural – 1.0 EcIg

Shear – 1.0 GcAg Flexural – 0.25 EcIg

Shear – 0.5 GcAg Flexural – 0.25 EcIg

Flexural – 0.3 EcIg

Flexural – 1.0 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Flexural – 0.07(l/h)( EcIg) ≤ 0.3EcIg

Flexural – 0.07(l/h)( EcIg) ≤ 0.3EcIg

Flexural – 0.3 EcIg

Flexural – 1.0 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg Flexural – 0.07(l/h)( EcIg) ≤ 0.3EcIg

Shear – 1.0 GcAg Flexural – 0.07(l/h)( EcIg) ≤ 0.3EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

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PBD Procedure: Expected Material Strength

Introduction to Performance-Based Design Component Non-PT transfer diaphragms (in-plane only) PT transfer diaphragms (in-plane only)

SLE/Wind (Strength) SLE/Wind (Service)

DBE

MCE

Flexural – 0.5 EcIg

Flexural – 1.0 EcIg

Flexural – 0.25 EcIg

Flexural – 0.1 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 0.5 GcAg

Shear – 0.1 GcAg

Flexural – 0.8 EcIg

Flexural – 1.0 EcIg

Flexural – 0.5 EcIg

Flexural – 0.1 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 0.1 GcAg

Tower Diaphragms (in-plane)

Flexural – 1.0 EcIg

Flexural – 1.0 EcIg

Flexural – 0.5 EcIg

Flexural – 0.5 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 0.5 GcAg

Shear – 0.5 GcAg

PT slab (out-of-plane)

Flexural – 0.5 EcIg

Flexural – 1.0 EcIg

Flexural – 1.0 EcIg

Flexural – 0.5 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Non-PT slab (out-of-plane)

Flexural – 0.25 EcIg

Flexural – 1.0 EcIg

Flexural – 0.25 EcIg

Flexural – 0.25 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

PBD Procedure: Expected Material Strength

Introduction to Performance-Based Design Component Girders

Columns

Mat (in-plane)

Mat (out-of-plane)

SLE/Wind (Strength)

SLE/Wind (Service)

DBE

MCE

Flexural – 0.5 EcIg

Flexural – 1.0 EcIg

Flexural – 0.35 EcIg

Flexural – 0.3 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Flexural – 0.7 EcIg

Flexural – 1.0 EcIg

Flexural – 0.7 EcIg

Flexural – 0.7 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Axial – 0.8 EcAg

Axial – 1.0 EcAg

Axial – 0.8 EcAg

Axial – 0.5 EcAg

Flexural – 0.8 EcIg

Flexural – 1.0 EcIg

Flexural – 0.8 EcIg

Flexural – 0.5 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Flexural – 0.8 EcIg

Flexural – 1.0 EcIg

Flexural – 0.8 EcIg

Flexural – 0.5 EcIg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

Shear – 1.0 GcAg

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PBD Procedure: Damping

Introduction to Performance-Based Design

PBD Procedure: Component Force vs Deformation Curves

Introduction to Performance-Based Design Deformation-Controlled and Force-Controlled Actions. All actions shall be classified as either deformation-controlled or force-controlled using the component force versus deformation curves.

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PBD Procedure: DeformationControlled Actions

Introduction to Performance-Based Design Deformation-Controlled Action: An action that has an associated deformation that is allowed to exceed the yield value of the element being evaluated. The extent of permissible deformation beyond yield is based on component modification factors (m-factors). ❑ Behavior is ductile and reliable inelastic deformations can be reached with no substantial strength loss. ❑ Results are checked for mean value of demand from seven (7) / eleven (11) sets of ground motion records.

Force-deformation relationship for deformation-controlled actions

Introduction to Performance-Based Design ❑

Type 1 curve is representative of ductile behavior

PBD Procedure: DeformationControlled Actions

where there is an elastic range (points 0 to 1 on the curve) and a plastic range (points 1 to 3), followed by loss of seismic-force-resisting capacity at point 3 and

loss of gravity load-resisting capacity at point 4. The plastic range can have either a positive or negative post-elastic slope (points 1 to 2) and a strengthdegraded region with non-negligible residual strength to resist seismic forces and gravity loads (points 2 to 3). Primary component actions exhibiting this behavior shall be classified as deformation controlled if the plastic range is such that 𝑑 ≥ 2𝑔; otherwise, they shall be classified as force controlled. Secondary component actions exhibiting this behavior shall be classified as deformation-controlled for any 𝑑/𝑔 ratio.

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Force-deformation relationship for deformation-controlled actions

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Introduction to Performance-Based Design Force-Controlled Action: An action that is not allowed to exceed the nominal strength of the element being evaluated. ❑ Behavior is more brittle and reliable inelastic

PBD Procedure: ForceControlled Actions

deformations cannot be reached. ➢

Critical action. Failure of which is likely

to lead to partial or total structural collapse. ➢

Ordinary action. Failure of which is either unlikely to lead to structural collapse or might lead to local collapse comprising not more than one bay in a single story.

Force-deformation relationship for force-controlled actions

Introduction to Performance-Based Design ❑ Type 3 curve is representative of a brittle or nonductile behavior where there is an elastic range (points 0 to 1 on the curve) followed by

PBD Procedure: ForceControlled Actions

loss of seismic-force resisting capacity at point 3 and loss of gravity-load-resisting capacity at the deformation associated with point 4. Primary component actions exhibiting this behavior shall be classified as force controlled. Secondary component actions exhibiting this behavior shall be classified as deformation controlled if 𝑓 ≥ 2𝑔; otherwise, they shall be classified as force controlled.

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Force-deformation relationship for force-controlled actions

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Introduction to Performance-Based Design PBD Procedure: Components Classified for Deformation-Controlled or Force-Controlled Actions

Component Shear walls Coupling beams (Conventional) Coupling beams (Diagonal) Girders Moment frame columns Outrigger columns

Diaphragms Basement walls Mat foundation Piles

Action Flexure

Classification Deformation-controlled

Criticality N/A

Shear Flexure Shear Shear Flexure Shear Axial Shear Axial-flexure Axial Shear Axial-flexure Chord Collector and shear friction Shear (Transfer diaphragms) Shear (Other diaphragms) Flexure Shear Flexure Shear Axial Axial-flexure Shear

Force-controlled Deformation-controlled Force-controlled Deformation-controlled Deformation-controlled Force-controlled Force-controlled Force-controlled Deformation-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled Force-controlled

Critical N/A Critical N/A N/A Critical Critical Critical N/A Critical Critical Ordinary Ordinary Critical Critical Ordinary Ordinary Ordinary Ordinary Critical Critical Ordinary Critical

PBD Procedure: Backbone Curves Vs Performance Levels

Introduction to Performance-Based Design The acceptance criteria for deformation-controlled actions used in nonlinear procedures shall be the deformations corresponding with the following points on the curves.

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PBD Procedure: Backbone Curves Vs Performance Levels

Introduction to Performance-Based Design

PBD Procedure: Backbone Curves Vs Performance Levels

Introduction to Performance-Based Design

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Introduction to Performance-Based Design

PBD Procedure: Evaluation for Service-Level Earthquake

Modeling and Analysis • Use linear model and response spectrum analysis. • Accidental eccentricities are not considered in serviceability evaluation. • 2.5% of critical damping • Load combinations • 𝟏. 𝟎𝑫 + 𝑳𝒆𝒙𝒑 ± 𝟏. 𝟎𝑬𝑺𝑳𝑬,𝒙 ± 𝟎. 𝟑𝑬𝑺𝑳𝑬,𝒚 • 𝟏. 𝟎𝑫 + 𝑳𝒆𝒙𝒑 ± 𝟎. 𝟑𝑬𝑺𝑳𝑬,𝒙 ± 𝟏. 𝟎𝑬𝑺𝑳𝑬,𝒚 𝑳𝒆𝒙𝒑 = Expected service live load which is 25% of unreduced live load • 𝑹, Ω𝟎, 𝝆, and 𝑪𝒅 are all taken as unity.

Acceptance Criteria • Member strength – 𝑫/𝑪 ≤ 𝟏. 𝟓 (Deformationcontrolled) – 𝑫/𝑪 ≤ 𝟎. 𝟕 (Forcecontrolled)

• Strength calculation – Use nominal material properties – Strength reduction factor = 1

• Story drift ≤ 0.5%

Introduction to Performance-Based Design

PBD Procedure: Evaluation for Service-Level Earthquake

[LATBSDC 2017]

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[TBI Ver. 2.03]

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PBD Procedure: Evaluation for MCE Level Earthquake

Introduction to Performance-Based Design • Use nonlinear model and nonlinear response history analysis. • Eleven pairs of site-specific ground motions are used. • Generally, 2.5% of constant modal damping is used with small fraction of Rayleigh damping for un-modeled energy dissipation. • Average of demands from eleven (11) ground motions approach is used. • Capacities are calculated using expected material properties and strength reduction factor of 1.0 for deformation-controlled actions.

PBD Procedure: Evaluation for MCE Level Earthquake

Introduction to Performance-Based Design Unacceptable Response

• Analytical solution fails to converge. • Predicted demands on deformation-controlled or forcecontrolled elements exceed the valid range of modeling. • Predicted deformation demands on elements not explicitly modeled exceed the deformation limits at which the

members are no longer able to carry their gravity loads.

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PBD Procedure: Acceptance Criteria

Introduction to Performance-Based Design Acceptance Criteria for Force-Controlled Actions Critical Action ▪ 1.0IeQNS + 1.3Ie (QT – QNS) ≤ ØsBRn

(a)

▪ 1.0IeQNS + 1.5Ie (QT – QNS) ≤ ØsBRnem (b)

Ordinary Action ▪ 1.0IeQNS + 0.9Ie (QT – QNS) ≤ ØsBRn

(c)

▪ 1.0IeQNS + 1.0Ie (QT – QNS) ≤ ØsBRnem (d)

PBD Procedure: Acceptance Criteria

Introduction to Performance-Based Design Ie =

Seismic importance factor appropriate to the Risk Category as defined in ASCE7 QT = Mean of the maximum values of the action calculated for each ground motion QNS = Non-seismic portion of QT B= Factor to account for conservatism in nominal resistance Rn, normally taken as having a value of 1.0. Alternatively, it can be taken as 0.9(Rne/Rn) for Eq. 4a and 4c and (Rne/Rnem) for Eq. 4b and 4d. Rn = Nominal strength of the force-controlled action, in accordance with the applicable material standard Øs = Resistance factor Rnem = Nominal strength for the action, determined in accordance with the applicable material standard using expected material properties Rne = Expected value of component resistance determined from test results using expected material properties

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PBD Procedure: Acceptance Criteria

Introduction to Performance-Based Design

Seismic Response Factor Action Type Critical force-controlled element Ordinary force-controlled element

Øs Ø as specified in the applicable material standard 0.9

Introduction to Performance-Based Design PBD Procedure: Acceptance Criteria

Item Peak transient drift Residual drift Coupling beam inelastic rotation Column (Axial-flexural interaction and shear) Shear wall reinforcement axial strain Shear wall concrete axial compressive strain Shear wall shear Girder inelastic rotation Girders shear Mat foundation (Flexure and shear) Diaphragm (In-plane response) Piles (Axial-flexural interaction and shear)

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Value Maximum of mean values shall not exceed 3%. Maximum drift shall not exceed 4.5%. Maximum of mean values shall not exceed 1%. Maximum drift shall not exceed 1.5%. ≤ASCE 41-17 limits Flexural rotation ≤ASCE 41-17 limits Remain elastic for shear response. ≤0.05 in tension and ≤0.02 in compression Unconfined concrete ≤ 0.003 Intermediately confined concrete ≤ 0.004 + 0.1 ρ (fy / f'c) Fully confined concrete ≤ 0.015 Remain elastic ≤ASCE 41-17 limits Remain elastic. Remain elastic. Remain elastic. Remain elastic.

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Acknowledgements

Introduction to Performance-Based Design

Special thanks to the following who are the sources of this presentation materials: ❑Dr. Naveed Anwar ❑Engr. Thaung Htut Aung

Thank you for your attention! End of Presentation! RETROFITTING CONCRETE BUILDINGS FOR ENVIRONENTAL SUSTAINABILITY

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