JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

Prerequisites

Reinforced Concrete Design, Steel Design, Concrete Technology

Course Objectives:

• To impart knowledge about different types of distress in structures
• Testing the structures for the deterioration of structures
• Testing the structures for the diagnosis of defects and different types of repairing methods.

Course Outcomes

After studying this course, students will be able to:

• Understand the cause of deterioration of concrete structures.
• Able to assess the damage for different type of structures
• Summarize the principles of repair and rehabilitation of structures
• Recognize ideal material for different repair and retrofitting technique

UNIT - I

Introduction – Definition of Repair, Retrofitting, Strengthening and rehabilitation, Deterioration of Structures – Distress in Structures – Causes and Prevention, Mechanism of Damage – Types of Damage, Physical and Chemical Causes of deterioration of concrete structures, Evaluation of structural damages to the concrete structural elements due to earthquake

UNIT - II

Corrosion of Steel Reinforcement – Causes – Mechanism and Prevention. Damage of Structures due to Fire – Fire Rating of Structures – Phenomena of Desiccation, Damage Assessment -,Purpose of assessment, Rapid assessment, Investigation of damage, Evaluation of surface and structural cracks, Damage assessment procedure, destructive, non-destructive and semi destructive testing systems -Influence on Serviceability and Durability- Effects due to climate, temperature, chemicals, wear and erosion, Design and construction errors, corrosion mechanism, Effects of cover thickness and cracking, methods of corrosion protection, corrosion inhibitors, corrosion resistant steels, coatings, and cathodic protection.

UNIT - III

Maintenance and Retrofitting Techniques: Definitions: Maintenance, Facts of Maintenance and importance of Maintenance Need for retrofitting, retrofitting of structural members i.e., column and beams by Jacketing technique, Externally bonding(ERB) technique, near surface mounted (NSM) technique, External post- tensioning, Section enlargement and guidelines for seismic rehabilitation of existing building, Inspection and Testing – Symptoms and Diagnosis of Distress - Damage assessment – NDT.

UNIT - IV

Repair of Structure – Common Types of Repairs – Repair in Concrete Structures – Repairs in Under Water Structures – Guniting – Shot Create – Underpinning. Strengthening of Structures – Strengthening Methods – Retrofitting – Jacketing.

UNIT - V

Materials for Repair and Retrofitting: Artificial fibre reinforced polymer like CFRP, GFRP, AFRP and natural fiber like Sisal and Jute. Adhesive like, Epoxy Resin, Special concretes and mortars, concrete chemicals, special elements for accelerated strength gain, Techniques for Repair: Rust eliminators and polymers coating for rebar during repair foamed concrete, mortar and dry pack, vacuum concrete,

Gunite and Shot Crete Epoxy injection, Mortar repair for cracks, shoring and underpinning- Health Monitoring of Structures – Use of Sensors – Building Instrumentation.

REFERENCES:

• 1. Concrete Technology by A.R. Santakumar, Oxford University press
• 2. Defects and Deterioration in Buildings, E F & N Spon, London
• 3. Non-Destructive Evaluation of Concrete Structures by Bungey - Surrey University Press
• 4. Maintenance and Repair of Civil Structures, B.L. Gupta and Amit Gupta, Standard Publications.
• 5. Concrete Repair and Maintenance Illustrated, RS Means Company Inc W. H. Ranso, (1981)
• 6. Building Failures: Diagnosis and Avoidance, EF & N Spon, London, B. A. Richardson, (1991).
• 7. “Deterioration, Maintenance and Repair of Structures “, Sidney, M. Johnson
• 8. “Concrete Structures – Materials, Maintenance and Repair”- Denison Campbell, Allen & Harold Roper, Longman Scientific and Technical.
• 9. “Learning for failure from Deficiencies in Design, Construction and Service” R.T.Allen and S.C. Edwards, “Repair of Concrete Structures”-Blakie and Sons Raiker R.N., - R&D Center (SDCPL).