Concrete Durability

Presentation by

Eng. B. Sambasiva Rao.

Curicullam Vitae

SAMBASIVA RAO

BANDLA

B.Sc (Maths);

B.E (Civil).

2012—2015 Arcop & Partners (Middle East)

Engineering Consultants LLC, Muscat.

1. Sultan Qaboos Youth Complex at

Salalah –

2. Al Hail Greens Residential

Development Phase-1—

3. Extention to Khoula Hosptial,

Muscat—

4. Old Age Home at Rustaq –

2011-2012 Aga Khan Academy, Hyderabad,

2009-2011 Dushanbe Serena Hotel, Dushanbe,.

Tajikistan

2009-2007 AWQAF, Office Complex, Dubai,

UAE.

2007-2001 Projects With BARC, Mumbai, India.

2001-1987 Projects with IGCAR, Kalpakkam,

Tamil Nadu, India.

1985-1987 Projects With M/s Coromandel

Engineering Comp. Ltd, Madras, India.

Bulk Storage Silo, GFCL,

Rock Phosphate Silo, PPLtd,

Propylene Recovery Unit,

Gas Turbine Generator,

Heat Recovery Steam Generator works,

for Madras Refineries Ltd, Chennai, India.

Sambasiva Rao is born in

Andhra Pradesh, India in

1958, graduated in Civil

Engineering from

Bangalore University,

Karnataka.

Mr. B.Sambasiva Rao, put

up rich and varied

experience in various

fields of Civil Engineering

since 1985 till date and

handled many a complex

and challenging projects.

Education

1984

Bachelors Degree in Civil

Engineering

1980

Bachelors Degree in

Mathematics,

Certificate Course:-

Executive Development,

NITIE, Powai, Bombay.

Camouflage Course,

CME, Pune.

(Project Management

Professional).

Historic Old Monuments

Pyramid Eroded Due to Weathering Agencies

Old Monuments of Egypt

Roman Colosseum

Roman Pantheon

Old Fort in Rajasthan, India

Durability Definition:-

Strength, toughness, sturdiness, robustness (healthiness), resilience (flexibility, compliance), permanence, endurance (staying power), indestructibility.

The literary meaning of durability is self explanatory. Any product/appliance/item we do consider for durability should have at least some of the inherent properties so defined.

Concrete Durability:-

• Concrete, said to perform its intended functions of maintaining designed strength and serviceability, is said to be durable only if it can be able to withstand process of deterioration it is expected to be exposed. (thanks to Neveli).

Prime Factors affecting Durability

• Water permeability—Absorbtion of concrete. ( porosity etc).

• Air and Vapour permeability –

• Carbonation---

• Frost and Thaw ( only in cold climates)

• Chloride attacks.

Concrete

• Cement as a definition is a material with cohesive and adhesive properties capable of bonding mineral aggregates into a compact mass. (thanks to Neveli).

• Concrete, is mix of fine and course aggregates bound by the Cement using water.

• Reinforced Cement Concrete (RCC) includes reinforced steel as another material of concrete matrix.

Bad and Good concrete:

• There is no such thing as how to make a bad concrete or Good concrete.

• All the components of the concrete with ideal parameters, should perform the role defined.

• It can be deviation from these, during the course of manufacture can only define the quality of concrete whether good or bad.

Some of the factors affecting the durability of Concrete

• Raw material utilized in production of Concrete:- Fine aggregates, Coarse Aggregates, Re-steel, type and grade of cement, quality of water, quality of Admixture, Ambient temperature.

• The quality of all these play an important role in making the concrete durable, by their inherent properties

Iron Pillar at Delhi1600 years old

Production of Concrete:

• Design mix to achieve the strength parameters, consideration of admixtures and water requirements to suit the conditions of atmosphere and climate ( cold and hot), water cement ratio, mixing of concrete.

• It should not be forgotten that strong concrete is not essentially a Durable concrete.

• Care should be taken to ensure a balance of both to achieve the defined parameter.

Workmanship

• Transport and placement.

Concrete Failures

Rusted Reinforcement

Failure of Form Work

Leak in Concrete

Concrete Degradation

Insufficient Cover Insufficient Cover

Concrete Failure

Case Study of Al Hail Green Residential Development, At Muscat.

Month SD

Oct'13 2.6

Nov'13 2.4

Dec'13 2.6

Jan'14 2

Feb'14 1.9

Mar'14 1.3

Apr'14 1.8

May'14 2

Jun'14 1.9

Jul'14 2.3

Aug'14 1.9

Sept'14 2.2

Oct'14 1.5

Nov'14 1.4

Dec'14 2

Jan'15 1.4

Feb'15 1.2

Mar'15 1

0

0.5

1

1.5

2

2.5

3

Oct'13 Nov'13 Dec'13 Jan'14 Feb'14 Mar'14 Apr'14 May'14 Jun'14 Jul'14 Aug'14 Sept'14 Oct'14 Nov'14 Dec'14 Jan'15 Feb'15 Mar'15

SD

SD

• THANK YOU