Application of reusable PZT sensors for monitoring intial hydration of concrete

• Main Author: Lim, Parry Weixiong.
• Other Authors: Yang Yaowen
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Civil engineering::Construction technology
• Online Access: http://hdl.handle.net/10356/15791
• Institution: Nanyang Technological University

For concrete structures, compressive strength information is essential during the curing period to determine the optimal demolding time. To avoid any significant long term ill effects on the structures, nondestructive structural health monitoring methods such as Electro Mechanical Impedance (EMI) sensing technique, which uses lead zirconate titanate (PZT) sensors, are employed as a built in monitoring system for strength gain monitoring of early age concrete. In this project, reusable PZT sensors will be developed and used for monitoring the initial hydration of concrete. To prevent any damage, the PZT will be bonded to an aluminum enclosure before insertion into concrete specimen. Using an impedance analyser, EM signatures will be detected during the curing period and processed by data software. The experiment will study the applicability of employing the EMI sensing technique to monitor early age concrete monitoring by analyzing the vertical and horizontal shifts in resonant peaks of EM signatures and using the Root Mean Square Deviation (RMSD) statistical method to show correlation of strength gain for curing from the signatures. More importantly, the experiment will prove that the PZT sensors can be reused, firstly by achieving reliable repeatable signature results, being able to be removed from concrete specimens without any damage and having similar or minor changes to the initial signature of the PZT sensor. These are important factors for the civil industry to ensure before implementing the reusable PZT sensors as a strength gain or damage detection monitoring system in structures.