InTrans / Aug 14, 2018
Early Detection and Eradication of Termite Infestations Destructive to Covered Bridge Structures Using Acoustic Emission
More than 1,500 covered bridges remain in the United States, and most are potentially subject to decay and termite damage. Nearly all termite damage to timber bridges in the United States occurs through subterranean termite colonies (especially Coptotermes and Reticulitermes species), which require contact with the soil or some other constant source of moisture. Severe internal decay of timbers used for bridge members is caused by white rot or brown rot fungi and promotes, if not attracts, subterranean termites. External surface decay, especially in ground contact areas, may also be caused by soft rot fungi. Other fungi, such as mold and sapstain fungi, may produce superficial discoloration on timbers but are generally not of structural significance. Advanced fungal decay can also act to attract termite infestations by wetting the wood structure and softening the substrate for termite infestation.