Bridge Failure
Bridge Failure
Studies
and Safety
Engineering
2.1 HISTORY OF DISASTERS AND SAFETY MANAGEMENT
2.1.1 Unexpected Material Deterioration and Failure
Engineering is usually about avoiding failures and investigating why failures occur and ways to fix the problem. There is a need to understand the conditions giving rise to past failures and ways to avoid such failures so that loss of life can be minimized. Historical events and selected case stud-ies demonstrate the causes of each type of failure. Future design codes can make use of the deficiencies identified in order to develop guidelines for safe practice. If failures are interpreted correctly, a great deal of information for correct analysis, anticipated behavior, detailed design, and construction can be obtained to help formulate accurate design guidelines.
Failures occur in different forms in a material. Physical forms of failure can be seen as infinitely large deformation and metallurgical disintegration of elements. It can be localized cracking without collapse or discontinuity or total separation in a component.
At failure, critical sections for plastic hinges are located at the midspan of beams or under the concentrated load where deflection or bending moment is highest. It can also be at a support where shear force, reaction, or negative bending moment is the highest.
Failures are encountered on construction sites and are not just confined to the collapse of structures. Deaths and injuries to construction workers by far exceed the number of fatalities of the bridge users in failure events. Structural design methods related to construction loads and equipment need to be refined.
Physical causes are varied such as erosion, reversal of stress, impact, vibra-tions, wind, and extreme events. Usually, it is a combination of dead load stress
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Studies
and Safety
Engineering
2.1 HISTORY OF DISASTERS AND SAFETY MANAGEMENT
2.1.1 Unexpected Material Deterioration and Failure
Engineering is usually about avoiding failures and investigating why failures occur and ways to fix the problem. There is a need to understand the conditions giving rise to past failures and ways to avoid such failures so that loss of life can be minimized. Historical events and selected case stud-ies demonstrate the causes of each type of failure. Future design codes can make use of the deficiencies identified in order to develop guidelines for safe practice. If failures are interpreted correctly, a great deal of information for correct analysis, anticipated behavior, detailed design, and construction can be obtained to help formulate accurate design guidelines.
Failures occur in different forms in a material. Physical forms of failure can be seen as infinitely large deformation and metallurgical disintegration of elements. It can be localized cracking without collapse or discontinuity or total separation in a component.
At failure, critical sections for plastic hinges are located at the midspan of beams or under the concentrated load where deflection or bending moment is highest. It can also be at a support where shear force, reaction, or negative bending moment is the highest.
Failures are encountered on construction sites and are not just confined to the collapse of structures. Deaths and injuries to construction workers by far exceed the number of fatalities of the bridge users in failure events. Structural design methods related to construction loads and equipment need to be refined.
Physical causes are varied such as erosion, reversal of stress, impact, vibra-tions, wind, and extreme events. Usually, it is a combination of dead load stress
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