Synthesis Study: Heat Treatment and Its Effects on Rehabilitating Steel Bridges in Indiana

Synthesis Study: Heat Treatment and Its Effects on Rehabilitating Steel Bridges in Indiana
Author: Matthew Lackowski
Publisher: Purdue University Press
Total Pages: 78
Release: 2007-01-01
Genre: Transportation
ISBN: 9781622601134

Significant research has been conducted on the development of: (1) heat straightening repair techniques and their field implementation, (2) guidelines and recommendations for heat straightening repair, (3) empirical procedures for estimating plastic rotations achieved during heat straightening, (4) empirical procedures for predicting residual stresses caused by heat straightening, and (5) the effects of heat straightening on the structural properties of repaired bridges. Currently, there is a need for additional research on: (a) the fatigue performance of heat straightened beams, (b) the effects of single and multiple heat straightening on the fracture toughness and microstructure of steel beams, (c) the development of guidelines for evaluating and replacing steel beams subjected to single or multiple damage-repairs, and (d) investigating the effects of realistic heat straightening with imperfections on the properties and serviceability of steel beam bridges. The literature review of existing heat treatments indicates that heat straightening with maximum temperature limited to 1200 F is relatively similar to the process annealing heat treatment. Heat straightening with maximum temperature limited to 1400oF is similar to the normalizing annealing heat treatment. Both these heat treatments repair plastically deformed microstructure by the phenomenon known as recovery and recrystallization. Normalizing annealing is more efficient and faster than process annealing in repairing the plastically deformed microstructure by recrystallization. Heat treatment and repair of the material microstructure is incidental to the heat straightening repair process. The heat straightened beam can be further heat treated to complete the repair of the material microstructure (recrystallization etc.). The practical and economic feasibility of additional heat treatment using electrically powered and controlled radiant heaters was evaluated and found to be reasonable.

Heat-straightening Repair of Damaged Steel Bridge Girders

Heat-straightening Repair of Damaged Steel Bridge Girders
Author: Robert J. Connor
Publisher: Transportation Research Board
Total Pages: 140
Release: 2008
Genre: Transportation
ISBN: 0309099374

TRB¿s National Cooperative Highway Research Program (NCHRP) Report 604: Heat-Straightening Repair of Damaged Steel Bridge Girders: Fatigue and Fracture Performance explores limits, based on fatigue and fracture performance, on the number of damage and repair cycles to which damaged steel bridge girders may be subjected using the heat-straightening procedure.

An Introduction to Steel Bridge Maintenance and Repair

An Introduction to Steel Bridge Maintenance and Repair
Author: J. Paul Guyer, P.E., R.A.
Publisher: Guyer Partners
Total Pages: 48
Release: 2019-11-27
Genre: Technology & Engineering
ISBN:

Introductory Technical Guidance for civil and structural engineers and construction managers interested in maintenance and repair of steel bridges. Here is what is discussed: Preventive Maintenance for Corrosion 1. INTRODUCTION 2. STRUCTURAL STEEL Repair and Strengthen 3. GENERAL REPAIR 4. CONNECTIONS 5. REPAIR OF STRUCTURAL MEMBERS Member Replacement 6. TENSION MEMBERS 7. COMPRESSION MEMBERS/COLUMNS 8. BEAMS Upgrade Steel Bridges 9. CREATION OF A COMPOSITE ACTION 10. POSTTENSIONING 11. TRUSS SYSTEMS

Effects of Multiple Damage-heat Straightening Repairs on the Structural Properties of Bridge Steels

Effects of Multiple Damage-heat Straightening Repairs on the Structural Properties of Bridge Steels
Author: Amit Hariom Varma
Publisher:
Total Pages:
Release: 2004
Genre: Iron and steel bridges
ISBN:

The effects of multiple damage-heat straightening repair events on the structural properties and fracture toughness of A36, A588, and A7 bridge steels were investigated experimentally. The damage and repair parameters included in the project are: (i) the damage strain, (ii) the restraining stress, (iii) the number of damage-repair cycles, and (iv) the maximum heating temperature. Extensive laboratory-scale and large-scale tests were conducted to evaluate the effects of these parameters on the structural properties including: (a) elastic modulus, (b) yield stress, (c) ultimate stress, (d) % elongation, (e) surface hardness, (f) fracture toughness, and (g) microstructure. Ninety-one laboratory-scale specimens, and six large-scale beam specimens made from A36, A588, and A7 steel were tested.