1. EARTHQUAKE
ENGINEERING
2.7. Equivalent Static
Load Method
2.7.1. Egyptian Code
2.7.2. UBC Code

2. 2.7. Equivalent Static Load Egyptian Code
Base Shear
Base Shear V=Z.I.K.C.S.W
W4
Z Zone Factor W1
I Importance Factor
K Structural System Factor H4 W2
C Structure Factor H3
S Soil Factor H2
W1
H1
W Design Weight
Prof.Dr. Osman Shaalan
2 Earthquake Engineering Dr. Tharwat Sakr

3. 2.7. Equivalent Static Load Egyptian Code
Zone Factor
Prof.Dr. Osman Shaalan
3 Earthquake Engineering Dr. Tharwat Sakr

4. 2.7. Equivalent Static Load Egyptian Code
Importance
Factor
Prof.Dr. Osman Shaalan
4 Earthquake Engineering Dr. Tharwat Sakr

5. 2.7. Equivalent Static Load Egyptian Code
Structural System Factor
Prof.Dr. Osman Shaalan
5 Earthquake Engineering Dr. Tharwat Sakr

6. 2.7. Equivalent Static Load Egyptian Code
Structure Factor
1
C= C ≤ 0.12
15 T
Prof.Dr. Osman Shaalan
6 Earthquake Engineering Dr. Tharwat Sakr

7. 2.7. Equivalent Static Load Egyptian Code
Soil Factor
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7 Earthquake Engineering Dr. Tharwat Sakr

8. 2.7. Equivalent Static Load Egyptian Code
Design Weight
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8 Earthquake Engineering Dr. Tharwat Sakr

9. 2.7. Equivalent Static Load Egyptian Code
Story Forces
Ft = 0.07 × T × V
Top Story Additional
Force
Ft = 0.0 For T < 0.7
Ft ≤ 0.25V
WjH j
Story Forces Fj = N
(V − Ft )
∑ (W H )
i =1
i i
Prof.Dr. Osman Shaalan
9 Earthquake Engineering Dr. Tharwat Sakr

10. 2.7. Equivalent Static Load Egyptian Code
Design Eccentricity
ed = e ± 0.05 B
e Actual eccentricity
0.05B Accidental eccentricity
B Building Breadth
Prof.Dr. Osman Shaalan
10 Earthquake Engineering Dr. Tharwat Sakr

11. 2.7. Equivalent Static Load Egyptian Code
Building Example
Building RC B+G+10+R
Floor Plan As shown in the drawing
Floors Basement 4m Parking
Ground 5m Commercial
First 5m Commercial
Typical 3.5m Office
Roof 3m Roof
Location Zagazig
Soil medium dense clay 20m then Sand
Prof.Dr. Osman Shaalan
11 Earthquake Engineering Dr. Tharwat Sakr

12. 2.7. Equivalent Static Load Egyptian Code
Floor Area 800 m2 (assumed 20X40m)
Roof Area 200 m2
Slab thickness 200mm

13. 2.7. Equivalent Static Load Egyptian Code
Building Example
Solution V = ZIKCSW
Zone Factor Z =0.2 Zone 2
Importance factor I =1 Commercial
Structural System K =1.33
Soil factor =1.15
Time Period (formula1) =0.1*13 =1.3 sec
(formula 2) =0.9*52/√20 =0.976 sec
Structure Factor C =1/15 √T =0.0675

14. 2.7. Equivalent Static Load Egyptian Code
Loads DL 0.2*25+2+3.5
= 10.5 kN/m2
Design Weight =(10.5+5)*20*40
=12400 kN Ground, first
and =(10.5)*20*40
=8400 kN floors above first
and =(10.5)*200
=2100 kN roof
Total Weight =12400*2+8400*10+2100
=110900 kN

15. 2.7. Equivalent Static Load Egyptian Code
Base Shear V =0.2*1*1.33*.0675*1.15*110900
=2289 kN
Top Force =0.07*1.05*2289
=156.4 kN

16. 2.7. Equivalent Static Load Egyptian Code
Floor w ELEV WH Forces
0 12400 4 49600 38.3
1 12400 9 111600 86.18
2 8400 14 117600 90.81
3 8400 17.5 147000 113.5
4 8400 21 176400 136.2
5 8400 24.5 205800 158.9
6 8400 28 235200 181.6
7 8400 31.5 264600 204.3
8 8400 35 294000 227
9 8400 38.5 323400 249.7
10 8400 42 352800 272.4
R 8400 45.5 382200 295.1
TR 2100 48.5 101850 78.65
SUM 110900 2762050 2133