Materiales de construccion

Proceedings of the 2007 IEEE International Conference on Networking, Sensing and Control, London, UK, 15-17 April 2007

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Smart Aggregates: a Distributed Intelligent Multi-purpose Sensor Network (DIMSN) for Civil Structures
G. Song, H. Gu and Y.L. Mo
During its service, it is important to detect impact, such as those caused by vehicles, ships, or barges, to the structure and tocontinuously evaluate the structure health status. Presently, there is no single transducer can perform all these tasks at a low cost. With recent development in sensors and
microprocessors, it is now possible to develop a single

Abstract- Early-age strength monitoring, impact detection, and structural health monitoring are important issues for concrete structures, especially concreteinfrastructures such as

bridges. A Distributed Intelligent Multi-purpose Sensor Network (DIMSN) using innovative piezoelectric-based smart aggregates is proposed in this paper to address these important issues. The

smart aggregate is fabricated by embedding a water-proofed piezoelectric patch into a small concrete block. The smart aggregates are then placed at the desired locations in concrete structuresbefore casting to form a distributed intelligent multi-

aggregates and the DIMSN. The early-age strength monitoring is performed by monitoring the harmonic response amplitude of smart aggregates. Experimental results show that the predicted concrete strength matches the experimental results obtained in the compressive test. Impact tests are by performed by impacting
the concrete frame atdifferent locations. Experimental results show that the impact response is captured by the distributed

purpose sensor network. In this paper, a two-story concrete frame is used as the object to test the multi-functionality of smart

transducer to perform early-age strength monitoring, impact detection, and structural health monitoring for concrete structures, especially for concreteinfrastructures, such as concrete bridges. This technology is the piezoceramic-based
embedded PZT (Lead Zirconate Titanate, a type of piezoceramic) patch. This smart

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aggrete The sat aggreg concrete block with a wired
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aggregate with an associated microprocessor is intelligent since it can sense and actuate. This smart aggregate is multifunctional andcan be used for early-age strength monitoring,
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smart aggregates and the energy of the impact response is related to the distance between the smart aggregate and the impact location. After the concrete strength is fully developed, structural health monitoring is conducted on the concrete frame through a destructive push-over test. Experimental results show that the
proposed damage indexmatrix reveals the time history of health status of different locations. The proposed smart aggregate-based

to address the important issues associated with concrete structures. These include the early-age concrete strength monitoring, impact detection & evaluation, and the structural health monitoring. A two-stor concrete frame instrumented
with the proposed multi-purpose smart aggregates iSused as
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to form a distributed intelligent multi-purpose sensor network

and structualedalt ntrig. Imathdet piezoelectric based-smart aggregates are used m In this paper,
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health monitoring approach is more sensitive than the traditional approaches that use microscopes and LVDTs. The proposed distributed intelligent multi-purpose sensor network has the potential to be implemented to thecomprehensive performance evaluation of concrete civil structures.

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early age strength monitoring

Index Terms-Sensor network, Smart aggregate, Piezoelectric matria, Halh mnitrin, mpat dtecio, ad Cncrte

the testing object. Experimental results show that the proposed intelligent multi-purpose sensor network can monitor the concrete strength in the early-age of concrete. After...