____________________________________________________ ARCH5023/ARCH4343 - ARCHITECTURAL STRUCTURES II

CONCRETE STRUCTURES

THE UNIVERSITY OF OKLAHOMA - COLLEGE OF ARCHITECTURE ____________________________________________________

SEISMIC DESIGN

V = 2.5 * Av * I *K * C * S * W

V = Total Lateral Force

Shear at the Base

Av = Peak velocity

I = Occupancy importance

K= Horizontal Force Factor

C= Coefficient

c = 1 / 15 x T

S= Soil Factor

W = Weight of Building

Av = Peak velocity related

Acceleration

0.40 = Seismic 4

0.30 = Seismic 3

0.20 = Seismic 2

0.10 = Seismic 1

0.05 = Seismic 0

0.15 = State of Oklahoma

I = Occupancy importance

1.5 = hospital

1.25 = over 300 people

1.0 = residential

k= Horizontal Force Factor

k = 4.0 masonry shear

wall in zone 2

k = 2.5 tanks

k = 2.0 none-buildings

k = 1.5 concrete

k = 1.0 steel

k = 0.87 special frames

k = 0.8 moment frames

C= Coefficient

c = 1 / 15 x T

T = duration of vibration

in seconds

S= Soil Factor

S1 = 1.0 = rock, gravel

S2 = 1.2 = stiff clay > 200'

S3 = 1.5 = clay > 30'

WIND DESIGN AND EARTHQUAKE DESIGN COMBINED UBC & BOCA

Example:

Hotel

10 stories

9' story height

fin. floor to fin. floor

100' long x 120' wide

concrete construction

flat roof

down-town

Dallas, Texas

Soil = heavy clay

UBC - Wind

qs = 0.00256

BOCA - Wind

Pd = Pe x I x I x Cp

BOCA - Seismic

V = 2.5 x Av x I x K x C x S xW

Example Problem BOCA Seismic Loads:
Calculate the Total Lateral Shear Force at Base (V)
under BOCA 
for a Hotel
100' long x 120' wide rectangular shape
10 floors
9' story height finished floor to fin. floor
flat roof
to be built in Downtown
Dallas, Texas
using concrete construction

A. Given:
BOCA
Hotel
100' long x 120' wide
rectangular shape
10 floors
9' story height finished floor to fin. floor
flat roof
Downtown Location
Dallas, Texas
concrete construction

B. Asked:
Calculate the Total Lateral Shear Force at Base (V) under BOCA

C. Graph:


10 floor
9' fl height

100' long
                               120' wide
Hotel
Concrete Structure
Downtown
Dallas, Texas

D. Calculations:

1. Location
		Dallas Texas

2. Obtain Seismic Zone
		Map of Seismic Zones and
		Effective Peak Velocity
		-Related Acceleration (Av)
		(Fig. 1113.1 BOCA map)

3. Locate Dallas/Fort Worth Metro Plex
		Seismic Zone 0

4. Effective Peak Velocity-Related 	Acceleration (Av)
	for Seismic Zone 0 = 0.05
		from same table

5.  I = Importance Factor Seismic
		1.5   = hospital
		1.25 = over 300 people
		1.0   = residential
		For Hotel select 1.25

6. k= Horizontal Force Factor
		k = 4.0 masonry shear wall in zone 2
		k = 2.5 tanks
		k = 2.0 none-buildings
		k = 1.5 concrete
		k = 1.0 steel
		k = 0.87 special frames
		k = 0.8 moment frames

		concrete construction  k = 1.5

7.   T = Duration of vibration 
		assume 1 second

8. C = Coefficient
		C = 1/15 x square root of T
		C = 1/15 x 1
		C = 0.06666 x 1
		C = 0.06666

9. S= Soil Factor
		S1 = 1.0 = rock, gravel
		S2 = 1.2 = stiff clay > 200'
		S3 = 1.5 = clay > 30'

		Given Dallas Soil clay > 30'
		S = 1.5

10. Weight of Building

11. Area= L x w
		   	Area = 120' x 100'
			Area = 12,000 sq ft

12. Concrete Deck = 12.5 lb/in/sqft 
	assume 6" thickness	
	6 x 12.5 lb/sqft = 75 lb/sqft
	to account for columns, walls, etc.
	we double this number
	75 lb/sqft x 2 = 150 lb/sqft

13. Weight per Floor
		12,000 sqft x 150 lb/sqft = 1,800,000 lb

14. Weight of Building
		10 floors + roof = 11
		1,800,000 lb x 11= 19,800,000 lb

15.	
V = 2.5 * Av * I *K * C * S * W
V = 2.5*0.05*1.25*1.5*0.066*1.5*19,800
V = 0.023203 * 19,800 
V = 459.4194
V = 460,000