Detailed Earthquake Design Analysis for a Melbourne Building Project

This assignment provides a detailed earthquake design analysis for a 4-story moment resisting concrete frame building located in Melbourne. The analysis follows the guidelines of AS 1170.4 (1993/2007) and includes calculations for dead and live loads, probability and hazard factors, natural period, design spectral response, and design category determination. The document further calculates base shear, storey earthquake load distribution, bending moments, and torsion at the base. Additionally, it addresses the design of parts and components, providing comprehensive calculations and relevant references to support the analysis. This assignment is a complete example of structural earthquake design, suitable for civil engineering students. This assignment is available on Desklib, a platform providing AI-based study tools.

RUNNING HEAD: EARTHQUAKE DESIGN
NAME
UNIT
ASSIGNMENT
ASSESSMENT NUMBER

RUNNING HEAD: EARTHQUAKE DESIGN
INFORMATION GIVEN:
Storeys = 4
Height = 16m
Lateral Dimensions = 25m × 25m
Eccentricity = 2m
Importance Class = Level 3
Site Soil Type = Type C
City = Melbourne
Return Period = 1000 years
Ductility = Limited (Default detailing in AS3600)
Structure Type = Moment Resisting Concrete Frame
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RUNNING HEAD: EARTHQUAKE DESIGN
Table 1: Calculation Table
REF:
AS
1170.4.1993/
2007
CALC. OUTPUT
Cl. 1.6.1 (2007) Assume 150mm for slab thickness.
Concrete density = 24kN/m3.
Self-weight = 0.15 × 24kN/m3
= 3.6 kPa
Self Wt. + D.L. = 11.6 kPa
Area = 25 × 25
= 625m2
LOADING
Loading: (deal load = 8 kPa; live load = 4 kPa typical floors and 1 kPa
roof.
Dead Load
Table 2: Dead Load
Level Calc. Load (kN) Mass (t)
Roof 625 × 11.6 7250 739.04
3(625 × 11.6) 3(7250) 3(739.04)
Total Load 29000 2956.17
Live Load
Table 3: Live Load
Level Calc. Load (kN) Mass (t)
Roof 625 × 1 625 63.71
3(625 × 4) 3(2500) 3(254.84)
Total Load 8125 828.24
Total building weight = G + ΨQ where Ψ = 0.3
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RUNNING HEAD: EARTHQUAKE DESIGN
Total building weight = 29000 × 0.3(8125) = 31437.5kN
Table 3.1 (2007) Probability Factor: Since the return period is 1000 years Kp = 1.3
Table 3.2 (2007) Hazard Factor: For a site in Melbourne Z = 0.08
Equation 6.2(7)
(2007)
Natural Period T1
Since structure type is MRCF = kt = 0.075
T1 = 1.25kthn0.75
T1 = 1.25 × 0.075 × 160.75 T1 = 0.75
Table 6.4 (2007) Since T1 = 0.75s Ch(T1) = 1.56
Table 6.5(A)
(2007)
Since Ductility is limited and structure type is OMRCF
μ = 2
Sp = 0.77 Sp/μ = 0.385
Table 2.1 (1993) Design Category:
KpZ = 1.3 × 0.08 = 0.104
Importance Class 3
Soil Class C
Structure height = 16
Design
Category II
Equation 6.2(3)
(2007)
EDC II Static Analysis
Base Shear (V) = Kp[ZCh(T1)][Sp/μ]W
V = 1.3[0.08 × 1.56 × 0.385]31437.5 V = 1961.7kN
Equation 6.3(2)
(2007)
Storey Earthquake Load Distribution
Fi =V
wi hi
∑
j =i
n
w j hj
Acceleration per floor = Force per floor (Fi)/Mass of floor (Wi)
Table 4: Earthquake Loading and Acceleration
Level (hi) (wi) wihi Fi(kN) Mass (t) Acceleration
(N/Kg)
Roof 16 7437.5 119000 750.62 802.75 0.935
3 12 8000 96000 605.54 993.88 0.609
2 8 8000 64000 403.69 993.88 0.406
1 4 8000 32000 201.85 993.88 0.203
T Storey Bending Moment
Bending moment per floor = Fi × hi
So total bending moment: M =∑
j=i
n
F j ( hj −hi)
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RUNNING HEAD: EARTHQUAKE DESIGN
Table 5: Bending Moment
Level Force (Fi) Height (hi) Moment (kNm)
Roof 750.62 16 12009.92
3 605.54 12 7266.49
2 403.69 8 3329.52
1 201.85 4 807.4
Total 23413.33
6.5.3 (1993) Torsion at Base
Torsion = V × e
es = 2m
ed1 = A1es + 0.05b where A1 = 1.4
ed2 = A2es – 0.05b where A2 = 0.5
ed1 = 1.4(2) + 0.05(25) = +4.05m
ed2 = 0.5(2) – 0.05(25) = -0.25m
Therefore e = 4.05m
Torsion = 4.05 × 1961.7
Mt =
7944.89kNm
8.2 (2007) Parts and Components
Wc = 2kN
Ductile, non-critical and rigidly fixed:
Fc = afloor[Icac/Rc]Wc
afloor = 0.1m/s2
Ic = 1.0
ac = 1.0
Rc = 2.5
Wc = 2kN
Fc = 0.935[1.0 × 1.0/2.5]2 Fc = 0.748kN
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RUNNING HEAD: EARTHQUAKE DESIGN
REFERENCES:
Australian Building Codes Board. (2009). BCA 2009: Building Code of Australia, Australian Building
Codes Board.
Australian Building Codes Board. (2010). An investigation of possible Building Code of Australia
(BCA) adaptation measures for climate change. Australian Building Codes Board, Canberra.
Australian Building Codes Board. (2013). National Construction Code Series Volume 1, Building
Code of Australia 2013, Class 2 to 9 Buildings. Canberra: Australian Building Codes Board.
Das, R. K., Samadder, N., & Azad, G. M. S. I. (2016). Analytical Study of Reinforcement
Consumption and Cost Management Due to Seismic Zoning. American Journal of Civil
Engineering, 4(6), 314-318.
Neville, A. M. (2002). Properties of Concrete (5th ed.). Harlow, U.K.: Pearson Education Limited.
Rama Raju, K., Cinitha, A., Kamatchi, P., & LYER, N. (2009). Estimation of enhanced design base
shear for strengthening the existing RC buildings designed as per IS Codes Prior To IS:
1893-2002 By Seismic Coefficient Method. Journal of the Institution of Engineers. India. Civil
Engineering Division, 90(AOU), 9-13.
Reddy, D. K., & Tupat, S. A. (2014). The effect of zone factors on wind and earthquake loads of high-
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Conference on Advances in Engineering & Technology (pp. 53-58).
SAI Global. (2011). Guide to Standards - Building and Construction. SAI GLOBAL.
Shah, H. J., & Jain, S. K. (2009). Design Example of a Six Storey Building. Department of Applied
Mechanics MS University of Baroda, Vadodara.
Standards Australia (1993). AS 1170.4 Minimum design loads on structures. Sydney: Standards
Australia.
Standards Australia. (2007). AS 1170.4 Structural Design Actions: Earthquake actions in Australia.
Sydney: Standards Australia.
Standards Australia. (2011). AS 2870-2011 Residential Slabs and Footings. Sydney: Standards
Australia.
Varma, S., Malar, A., Thenmozhi, S., Suriya, T., Murali, G., Venugopal, B., & Karthikeyan, K.
(2014). Comparative Study of Seismic Base Shear of Reinforced Concrete Framed Structures
in Different Seismic Zone. The International Journal of Science and Technoledge, 2(8), 74.
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Victoria State Government. (2017). The Building Interim Regulations 2017. Melbourne, VU: Victoria
State Government.
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