© 2018 JETIR September 2018, Volume 5, Issue 9 www.jetir.org (ISSN-2349-5162) JETIR1809576 Journal of Emerging Technologies and Innovative Research (JETIR) www.jetir.org 485 Smart Sensor Technics for Structural Health Monitoring of Civil Engineering Structures Payal B. Rangari 1 , Sanjay K. Bhadke 2 1 M-Tech Research Scholar, Department of Civil Engineering, Tulsiramji Gaikwad-Patil College of Engineering and Technology, Mohgaon, Nagpur, MH. 2 Asst. Professor, Department of Civil Engineering, Tulsiramji Gaikwad-Patil College of Engineering and Technology, Mohgaon, Nagpur, MH. Abstract— Structural Health Monitoring (SHM) aims to develop automated systems for the continuous monitoring, inspection and damage detection of structures with minimum labour involvement. The first step to set up a SHM system is to incorporate a level of structural sensing capability that is reliable and possesses longterm stability. Smart sensing technologies including the applications of fibre optic sensors, piezoelectric sensors, magnetostrictive sensors and self - diagnosing fibre reinforced composites, possess very important capabilities of monitoring various physical or chemical parameters related to the health and therefore, durable service life of structures. In particular, piezoelectric sensors and magnetorestrictive sensors can serve as both sensors and actuators, which make SHM to be an active monitoring system. Thus, smart sensing technologies are now currently available, and can be utilized to the SHM of civil engineering structures. In these paper, the application of smart materials/sensors for the SHM of civil engineering structures is critically reviewed. The major focus is on the evaluations of laboratory and field studies of smart materials/sensors in civil engineering structure. Keywords—Structural Health Monitoring, piezoelectric sensor, fibre optic sensor 1. INTRODUCTION Civil engineering infrastructure is generally the most expensive national investment and asset of any country. In addition, civil engineering structures have long service life compared with other commercial products, and they are costly to maintain and replace once they are erected. Further, there are few prototypes in civil engineering and each structure leads to be unique in terms of materials, design and construction. The most important structures include bridges, high-rise buildings, power utilities, nuclear power plants, and dams. All civil structures age and deteriorate with time. The deterioration is mostly the result of aging of materials, continuous use, overloading, aggressive exposure conditions, lack of sufficient maintenance, and difficulties encountered in proper inspection methods. All of these factors contribute to material and structural degradation as internal and external damages emerge and coalesce, and then evolve and progress. To ensure structural integrity and safety, civil structures have to be equipped with Structural Health Monitoring (SHM), which aims to develop automated systems for the continuous monitoring, inspection, and damage detection of structures with minimum labour involvement. An effective SHM system can in real time and online to detect various defects and monitor strain, stress, and temperature so that the optimum maintenance of the structures can be carried out to ensure safety and durable service life. In general, a typical SHM system includes three major components: a sensor system, a data processing system (including data acquisition, transmission, and storage), and a health evaluation system (including diagnostic algorithms and information management). The first step to set up this system is to incorporate a level of stable and reliable structural sensing capability. So, this paper is mainly related to the first component of the SHM system: the sensing system formed by smart materials/sensors. Smart materials/sensors, such as fibre optic se nsors (FOS), piezoelectric sensors, magnetostrictive sensors, and self-diagnosing fibre reinforced structural composites, possess very important capabilities of sensing various physical and chemical parameters related to the health of the structures. Since shape memory alloys and magnetorheological fluids are often used as actuators, they are not introduced in this paper. FOS, for example, are small and therefore do not affect the performance characteristics of civil engineering structures in which they are embedded. A single fibre can efficiently monitor structural performance at various locations by using multiplexed or distributed sensing technologies. They are unperturbed by electromagnetic interference. Optical waves are suitable for long transmission distances of relatively weak signals. Piezoelectric and magnetorestrictive sensors can serve as both sensors and actuators, which make SHM to be an active monitoring system. Furthermore, they can come in a variety of sizes, allowing them to be placed everywhere, even in remote and inaccessible locations, to actively monitor the conditions of various types of structures. Since the subject matter of SHM has been growing rapidly