response spectrum by egyptian code seismic load

7/29/2019 Response Spectrum by Egyptian Code Seismic Load

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ASSIGNMENT NO. 2

Prepared By: Ahmed Shaban Mahmoud

Date : 24-Nov-2010


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Numerical Analysis Assignment NO.2 24-NOV-2010


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Q2. Draw the following curves in [Sae-T] and [Sae-Sde ] formats for both

response spectrum and Design Spectrum (Steel Frame with Welded

Connections)

Curve 1: All Soil Classes for ag=0.15g


Curve 3: All Design Ground Accelerations for Soil Class C

Curve 4: All Design Ground Accelerations for Soil Class B

Q3. Solve Question-of Exam-2009


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Solution

Q2. Show below figures


Figure: Elastic Spectral Acc. VS. Period T for all type of soil

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Elastic

SpectralAcc.

Sed

(g)

Period T (Sec.)

Acc. Spectrum (Elastic)

ag =0.15g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Design Spectral Acc. VS. Period T for all type of soil

0

0.1

0.2

0.3

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Design

SpectralAcc.

Sad

(g)

Period T (Sec.)

Acc. Spectrum (Design)

ag =0.15g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Elastic Spectral Acc. VS. Elastic Spectral Disp. for all

type of soil

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1.1

0.0000 0.0010 0.0020 0.0030 0.0040 0.0050 0.0060 0.0070 0.0080 0.0090 0.0100

ElasticSpectralA

cc.

Sae

(g)

Elastic Spectral Disp. Sde (m)


ag =0.15g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Design Spectral Acc. VS. Design Spectral Disp. for all

type of soil


0

0.05

0.1

0.15

0.2

0.25

0.0000 0.0020 0.0040 0.0060 0.0080 0.0100 0.0120 0.0140 0.0160

Design

Spec

tralAcc.

Sad

(g)

Design Spectral Disp. Sdd (m)


ag =0.15g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Elastic Spectral Acc. VS. Period T for all type of soil

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

ElasticSpectralAcc.

Sed

(g)

Period T (Sec.)


ag =0.3g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Design Spectral Acc. VS. Period T for all type of soil

0

0.1

0.2

0.3

0.4

0.5

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Design

Spectr

alAcc.

Sad

(g)

Period T (Sec.)

Acc. Spectrum (Design)ag =0.3g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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type of soil

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

2.2

0.0000 0.0050 0.0100 0.0150 0.0200

ElasticSpectralAcc.

Sae

(g)


Acc. Spectrum (Elastic)ag =0.3g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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type of soil

Curve 3: All Design Ground Accelerations for Soil Class C

0

0.1

0.2

0.3

0.4

0.5

0.0000 0.0050 0.0100 0.0150 0.0200 0.0250 0.0300 0.0350

Design

Spec

tralAcc.

Sad

(g)



ag =0.3g , =1.2

Soil Class A

Soil Class B

Soil Class C

Soil Class D


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Figure: Elastic Spectral Acc. VS. Period T for all ground acc.

type of soil C

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Elastic

SpectralAcc.

Sed

(g)

Period T (Sec.)


Soil Class C , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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Figure: Design Spectral Acc. VS. Period T for all ground acc.type of soil C

0

0.1

0.2

0.3

0.4

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Design

Sp

ectralAcc.

Sad

(g)

Period T (Sec.)


Soil Class C , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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ground acc. type of soil C

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

0.0000 0.0020 0.0040 0.0060 0.0080 0.0100 0.0120 0.0140

ElasticSp

ectralAcc.

Sae

(g)



Soil Class C , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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ground acc. type of soil C

Curve 4: All Design Ground Accelerations for Soil Class B

0

0.1

0.2

0.3

0.4

0.0000 0.0050 0.0100 0.0150 0.0200 0.0250 0.0300 0.0350

Design

Sp

ectralAcc.

Sad

(g)



Soil Class C , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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Figure: Elastic Spectral Acc. VS. Period T for all ground acc.

type of soil B

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Elastic

SpectralAcc.

Sed

(g)

Period T (Sec.)


Soil Class B , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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Figure: Design Spectral Acc. VS. Period T for all ground acc.

type of soil B

0

0.1

0.2

0.3

0.4

0 0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7 3 3.3 3.6 3.9 4.2

Design

SpectralAcc.

Sad

(g)

Period T (Sec.)


Soil Class B , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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ground acc. type of soil B

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0.0000 0.0020 0.0040 0.0060 0.0080 0.0100 0.0120

ElasticSpectralAcc.

Sae

(g)



Soil Class B , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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ground acc. type of soil B

Q3.1-Estimation Wind Force F4 according to ANSI

Basic wind speed (3-sec gust speed) = 100 mph = 44.704 m/s

0

0.1

0.2

0.3

0.4

0.0000 0.0050 0.0100 0.0150 0.0200 0.0250 0.0300 0.0350

DesignS

pectralAcc.

Sad

(g)



Soil Class B , =1.2

Region 1

Region 2

Region 3

Region 4

Region 5.a

Region 5.b


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Important factor (Structure category) I = 1.07

Terrain exposure constant : for terrain exposure B

= 4.5 Zg = 1200 ft = 365.76 m Do = 0.01

Kz = 2.58 ( Z / Zg )1/

qz = 0.613 Kz ( V I )2 ( N/m2 )

= 0.613 Kz * ( 1.07 * 44.704 )2 ( N/m2 )

Guest Factor G is calculated accord. ANSI as shown below.

B = 15m building width

h = 75m building height

H / B =75 / 15 = 5.0 So,building is rigid

Tz =. ( )

.

(

.)

. ( . ).

(

.)

= 0.1472

G = 0.65 + 3.65 Tz

= 1.18736

L / B = 25 / 25 = 1.0

Cp = 0.8 for windward wall

Cp = -0.5 for leeward wall

Wind On building :-

Floor

NO.

Z

( m )KZ I

qz( N/m2 )

Cp

(front+rear)Gh

Pz( N/m2 )

5TH

75 1.81 1.07 2544.6 1.3 1.1874 3928


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4th

60 1.73 1.07 2421.5 1.3 1.1874 3738

3rd

45 1.62 1.07 2271.5 1.3 1.1874 3506

AVG. 3724

Wind Force F4 = ( 3928+2*3738+3506 ) /4 * 25 * 15 /1000 = 1398 KN

Q3.2-Distributing Wind Force F4 = 1396 KN

By Upper Limit ( Rigid Diaphram )

Distribution is according to stiffness

Force in bracing at axis 1 or 3 = 8 / (8+1+8) * 1398 = 657.9 KN

Force in frame at axis 2 = 1 / (8+1+8) * 1398 = 82.2 KN

By Lower Limit ( NO-Diaphram )

Distribution is according to served area

Force in bracing at axis 1 or 3 = 1 / 4 * 1398 = 350 KN

Force in frame at axis 2 = 1 / 2 * 1398 = 699 KN

Q3.3-a. Seismic force according to Egypt code for loads

Check time period 0.8 sec 2.0 sec & 4 Tc (Tc atleast 0.25 ),and regular horizontal plan with regular vertical elevations.

So, Use simplified modal response spectrum method

Fb = Sd ( T1 ) . W / g

Where :-Sd ( T1 ) is design spectrum acceleration calculated for time period =0.8 sec- = 1.0 for T1 > 2.0 Tc


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-W/g is total mass of building

Distribution of force Fb may based first mode shape and may be by assuminglinear displacement over hight.

Fi =(

,

) * Fb

F4 =(

( )) * Fb = 0.267 * Fb

Q3.3-b. Distribution Seismic force F4 = 1396 KN

-By Upper Limit ( Rigid Diaphram )

Force applied at centre of mass (almost centre of plan) which is

same of centre of area

So, No changes in distribution than in item 2 above

-By Lower Limit ( NO-Diaphram )

Distribution is according to served mass

Each system served mass as same ratio of served wind area.

So, No changes in distribution than in item 2 above

response spectrum by egyptian code seismic load

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