Evaluation of Prestress Loss Distribution during Pre-Tensioning and Post-Tensioning Using Long-Gauge Fiber Bragg Grating Sensors.

摘要: Prestress loss evaluation in prestressed strands is essential for structures. However, the sensors installed outside duct can only measure total prestress loss. The attached on inside also have several problems, such as inadequate durability an aggressive environment and vulnerability to damage during tensioning. This paper proposes a new installation method long-gauge fiber Bragg grating (LFBG) prevent accidental damage. Then itemized losses were determined each stage of pre-tensioning post-tensioning according LFBG measurements. We verified applicability monitoring accuracy proposed calculation post-tensioning. In case, calculated had less deviation from true than those obtained foil-strain gauges, was better whereas close derived theoretical predictions. Finally, we monitored variation strand 90 days. at stages by show prospect practical evaluation.