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RELIABILITY ANALYSIS OF STEEL SMRF AND SCBF STRUCTURES CONSIDERING THE VERTICAL COMPONENT OF NEAR-F AULT GROUND MOTIONS Investigators: 1) Jawad Fayaz; Graduate Student 2) Farzin Zareian; Associate Professor Performance Based Earthquake Engineering Laboratory, University of California Irvine Estimate Type II Parameters u & k Type II Distribution- Curve Fitting - EQ Load Setting up Limit State Equations = BEAMS & BRACES = − + + + + COLUMNS D, L, E and R represent random variables for EDP due to Dead Load, Live Load, Earthquake Load and corresponding Resistance, respectively. The subscript CA denotes the respective component action Calculate: µ & = 1 − exp =1– = 0 Τ 1 2 2 2 | 2 Analysis Case Effective Nominal Resistance (R n ) Analyzed Under Case I Τ . + . +. . 2-D Ground Motions Case II Τ . + . +. . 3-D Ground Motions Case III Τ . + . + . +. . 3-D Ground Motions Case IV 2% Drift Based Design 3-D Ground Motions CASES OF ANALYSIS 1 SMRF 2-, 4-, 8- & 12- Story SCBF 3- & 6- Story 140 feet 100 feet 180 feet 120 feet 120 feet 180 feet SCBF 12- & 16- Story 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0 100 200 300 400 500 EDP due to Earthquake Load E RotD50 Spectral Acceleration (Sa) Dead Load - Normal Distribution = µ C.o.V = µ Calculate: µ & Live Load - Gamma Distribution = µ C.o.V = µ Calculate: µ & Resistance LogNormal Distribution = µ C.o.V = µ Calculate: µ & Limit State Equation FORM b 4 5 6 +. + , + , + r , 2 3 Current b of SMRF Members Current b of SCBF Members Empirical values to upgrade seismic load combinations Empirical values of x’ for the seismic load combinations can be derived from this figure depending on what percentage of members are required to attain Reliability = 1.75 (i.e. Probability of Failure = 4%) CASE I CASE II CASE III Reliability Index (b ) for Braces 1.0 1.2 1.4 1.6 1.8 2.0 CASE I CASE II CASE III Reliability Index (b ) for Columns 1.0 1.2 1.4 1.6 1.8 2.0 1.0 1.2 1.4 2.2 2.4 2.6 2.0 1.8 1.6 Reliability Index (b ) for Beams CASE: MOMENTS SHEAR I II III IV I II III IV CASE III CASE IV 1.0 1.2 1.4 2.2 2.4 2.6 2.0 1.8 1.6 Reliability Index (b ) for Columns CASE II CASE I 0.00% 0.20% 0.40% 0.60% 0.80% 1.00% 0 0.1 0.2 0.3 0.4 0.5 0.6 1.2 1.8 2.4 3 3.6 Frequency Probability Mass Cumulative Probability 0.5 PMF 0.0 0.6 1.2 1.8 2.4 3.0 3.6 CDF x - Values 0.4 0.3 0.2 0.1 0.0 1.0 0.8 0.6 0.4 0.2 0.0

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  • RELIABILITY ANALYSIS OF STEEL SMRF AND SCBF STRUCTURES CONSIDERING THE

    VERTICAL COMPONENT OF NEAR-FAULT GROUND MOTIONSInvestigators:

    1) Jawad Fayaz; Graduate Student 2) Farzin Zareian; Associate Professor

    Performance Based Earthquake Engineering Laboratory, University of California Irvine

    Estimate Type II Parameters

    u & k

    Type II Distribution-

    Curve Fitting - EQ Load

    Setting up Limit State Equations

    𝒁𝑪𝑨 = 𝑹𝑪𝑨 − 𝑫𝑪𝑨 − 𝑳𝑪𝑨 − 𝑬𝑪𝑨 BEAMS & BRACES

    𝒁𝑪𝒐𝒍𝒖𝒎𝒏 = 𝟏 −𝑫𝑨𝒙𝒊𝒂𝒍+ 𝑳𝑨𝒙𝒊𝒂𝒍+ 𝑬𝑨𝒙𝒊𝒂𝒍

    𝑹𝑨𝒙𝒊𝒂𝒍−

    𝑫𝑴𝒐𝒎𝒆𝒏𝒕+ 𝑳𝑴𝒐𝒎𝒆𝒏𝒕+ 𝑬𝑴𝒐𝒎𝒆𝒏𝒕

    𝑹𝑴𝒐𝒎𝒆𝒏𝒕COLUMNS

    D, L, E and R represent random variables for EDP due to Dead Load, Live Load,

    Earthquake Load and corresponding Resistance, respectively. The subscript CA

    denotes the respective component action

    Calculate:

    µ𝑬 & 𝝈𝑬

    𝐺𝐸 𝑒 = 1 − exp 𝜆𝐸𝑡

    𝐹𝐸 𝑒 = 1 – 𝐺𝐸 𝑒𝜆𝐸 = 𝑘0 Τ

    𝑒𝑎

    −𝑘𝑒𝑥𝑝1

    2

    𝑘2

    𝑏2𝜎 𝐿𝑁 𝐸 |𝑆𝑎

    2

    Analysis Case Effective Nominal Resistance (Rn) Analyzed Under

    Case I Τ𝟏. 𝟐𝐃𝐧 + 𝟎. 𝟓𝐋𝐧+𝟏. 𝟎𝑬𝐧 𝟎. 𝟗 2-D Ground Motions

    Case II Τ𝟏. 𝟐𝐃𝐧 + 𝟎. 𝟓𝐋𝐧+𝟏. 𝟎𝑬𝐧 𝟎. 𝟗 3-D Ground Motions

    Case III Τ𝟏. 𝟐 + 𝟎. 𝟐𝐒𝐃𝐒 𝐃𝐧 + 𝟎. 𝟓𝐋𝐧+𝟏. 𝟎𝑬𝐧 𝟎. 𝟗 3-D Ground Motions

    Case IV 2% Drift Based Design 3-D Ground Motions

    CASES OF ANALYSIS1

    SMRF 2-, 4-,

    8- & 12- Story

    SCBF 3- & 6-

    Story

    140 feet

    10

    0 f

    eet

    180 feet

    120 fe

    et 1

    20

    feet

    180 feet

    SCBF 12- & 16-

    Story

    𝑬

    𝑬

    0

    0.05

    0.1

    0.15

    0.2

    0.25

    0.3

    0.35

    0.4

    0.45

    0 100 200 300 400 500EDP due to Earthquake Load

    E

    RotD50 Spectral Acceleration (Sa)

    0k

    a a a aH S P S s k s

    0k

    a a a aH S P S s k s

    Dead Load - Normal Distribution

    𝐌 𝐚𝐧

    𝐍𝐨𝐦𝐢𝐧𝐚𝐥=

    µ𝑫𝑫𝒏

    C.o.V 𝑽 =𝝈𝑫µ𝑫

    Calculate:

    µ𝑫 & 𝝈𝑫

    Live Load- Gamma Distribution

    𝐌 𝐚𝐧

    𝐍𝐨𝐦𝐢𝐧𝐚𝐥=

    µ𝑳𝑳𝒏

    C.o.V 𝑽 =𝝈𝑳µ𝑳

    Calculate:

    µ𝑳 & 𝝈𝑳

    Resistance – LogNormal

    Distribution

    𝐌 𝐚𝐧

    𝐍𝐨𝐦𝐢𝐧𝐚𝐥=

    µ𝑹𝐑𝒏

    C.o.V 𝐕 =𝛔𝑹µ𝑹

    Calculate:

    µ𝑹 & 𝝈𝑹

    Limit State Equation FORM b

    4

    5

    6

    𝜸𝑫+ 𝟎. 𝟐 + 𝒙 𝑺𝑫𝑺 𝑫𝒏,𝑪𝑨 + 𝜸𝑳𝑳𝒏,𝑪𝑨 + r𝑬𝒏,𝑪𝑨

    2

    3

    Current b of SMRF Members

    Current b of SCBF Members

    Empirical values to upgrade seismic load combinations

    Empirical values of ‘x’ for the

    seismic load combinations can

    be derived from this figure

    depending on what percentage

    of members are required to

    attain Reliability = 1.75 (i.e.

    Probability of Failure = 4%)

    CASE I CASE II CASE III

    Reliab

    ilit

    y I

    nd

    ex (

    b )

    fo

    r B

    races

    1.0

    1.2

    1.4

    1.6

    1.8

    2.0

    CASE I CASE II CASE III

    Reliab

    ilit

    y I

    nd

    ex (

    b )

    fo

    r C

    olu

    mn

    s

    1.0

    1.2

    1.4

    1.6

    1.8

    2.0

    1.0

    1.2

    1.4

    2.2

    2.4

    2.6

    2.0

    1.8

    1.6

    Reliab

    ilit

    y I

    nd

    ex (

    b )

    fo

    r B

    eam

    s

    CASE:

    MOMENTS SHEAR

    I II III IV I II III IV CASE III CASE IV1.0

    1.2

    1.4

    2.2

    2.4

    2.6

    2.0

    1.8

    1.6

    Reliab

    ilit

    y I

    nd

    ex (

    b )

    fo

    r C

    olu

    mn

    sCASE IICASE I

    0.00%

    0.20%

    0.40%

    0.60%

    0.80%

    1.00%

    0

    0.1

    0.2

    0.3

    0.4

    0.5

    0.6 1.2 1.8 2.4 3 3.6

    Frequency

    Bin

    Probability Mass Cumulative Probability0.5

    PM

    F

    0.0 0.6 1.2 1.8 2.4 3.0 3.6

    CD

    F

    x - Values

    0.4

    0.3

    0.2

    0.1

    0.0

    1.0

    0.8

    0.6

    0.4

    0.2

    0.0