Which type of stress is induced by construction equipment during bridge erection?

• A. Erection stress
• B. Live load
• C. Dead load
• D. Thermal stress

Answer: (A)

During bridge erection, the structure experiences temporary, construction-stage forces from equipment like cranes and lifting gear. These forces create erection stress, which is the stress state in members specifically due to the loads imposed during the erection sequence. It’s different from service loads (live load) that come from traffic on a finished bridge and from the permanent weight of the structure (dead load). It’s also separate from thermal stress, which comes from temperature changes causing expansion or contraction. Erection stress is addressed in erection analyses to ensure the members can safely carry those temporary loads until the bridge is completed.