Civil Engineering/concrete slab

Advertisement

Expert: - 2/24/2010


Question
I would like to design a 9m x 6m concrete slab to carry a container weighing 6tons. May you help me with the design? I think a 150mm thick slab with mesh ref. 395 would be good enough assuming the load is uniformly distributed across the slab area. I need to establish the design criteria, etc so a worked example could help checking for all failure possibilities.
Thank you.

Answer
Hi Mosesseroka,

Due to liability reasons I do not do actual designs over this forum, just give advice.

I presume you are talking about a ground-bearing (grade) slab, in which case the design is determined to a great extent by the nature and compaction of the supporting soil/subgrade. If the subgrade is firm and the pressure is applied uniformly (which may be difficult to achieve for containers), then what you propose, even with an A-193 mesh would be sufficent. However, if the loading is concentrated at the corners or edges, then you may be better off in designing a strip-footing, say 0.6m wide, 200 to 250mm deep, with A-393 mesh at the bottom. This will apply a pressure of only 4 kN/m2 to the subgrade, which is nominal.

Civil Engineering

All Answers

Answers by Expert:

Ask Experts

Volunteer

Arshad Khan

Expertise

I can answer any questions to do with civil and structural engineering consultancy and construction industry in East Africa and the Middle East, and specifically with the analysis and design of reinforced concrete structures. My particular expertise is in the aseismic design and optimisation of tall buildings.

Experience

Employment history: 36 years in Construction and consultancy in the UK, Kenya, Tanzania, Uganda, Ethiopia, Eritrea, South Africa, Somalia, Zambia, Austria, Bahrain, Kuwait, Doha and the U.A.E.

Organizations
.Fellow of Institution of Structural Engineers (UK) .Fellow of Institution of Civil Engineers(UK) .Member of the Institution of Engineers, Kenya .Registered Engineer, ERB, Kenya .Member of the Architectural Association of Kenya (Engineers Chapter) .Chartered Engineer (UK)

Publications
•1984: International Conference on the Art and Practice of Structural Design, London •1994: 3rd Int. Kerensky Conference in Structural Engineering, Singapore •2008: International Conference on High-Rise Towers, Abu Dhabi

Education/Credentials
BSc, 1st Class Hons, in Building Engineering, University of Bath, UK MSc in Concrete Structures and Technology, University of London. Diploma of Imperial College, UK.

Awards and Honors
•Science Congress Special Award (for 2-seater Hovercraft - 1968) •Institution of Civil Engineers Award for outstanding performance at Bath University (1975) •Concrete Society Postgraduate study Bursary Award (1976) •Consular Representative for British High Commission, Nairobi. (1995 to 1998) •Examiner for Institution of Civil Engineers Professional Interviews, Nairobi. (1997 to 1998) •Branch Representative in Vienna for PI assessment for Inst. of Struct. Engrs. (1999 to date)

©2012 About.com, a part of The New York Times Company. All rights reserved.