Chapter 8 Static Deformation Analysis for Structural Health Monitoring of a Large Dam Jiann-Shiun Lew Abstract The structural health monitoring of a dam is important for maintaining the safe operation and the longevity of the dam system. The damage of a structure can be detected from the variation of structural features, such as structural vibration and static deformation. The structural health of a large dam cannot be continuously monitored from structural vibration since vibration is insignificant except when earthquakes happen. The use of the daily measured static deformation can be an alternative way to continuously monitor the long-term structural health of a dam. This paper presents an investigation with the use of the measured static deformation for the structural health monitoring of Fui-Tsui dam, which is located in a very active seismic zone of Taiwan. A modeling technique is applied to characterize the measured static deformation as a function of the measured physical parameters. The proposed technique can also be used for the prediction of the long-term deformation for the structural health monitoring of Fui-Tsui dam. Keywords Structural health monitoring • Large dam • Static deformation • Modeling • Statistical analysis 8.1 Introduction Structural health monitoring (SHM) is important in maintaining the performance, serviceability, and reliability of civil and aerospace structures. The damage of a structure can be detected from the variation of structural features, such as structural vibration and static deformation. Various methods, based on the dynamic and static tests, have been developed to address structural health monitoring and damage identification [1–3]. However, uncertainties in SHM systems, such as changing environmental conditions, operational variations and boundary conditions [4, 5], may significantly affect the measurements and reduce the reliability of damage identification with false indications of damage [6, 7]. Therefore, it is necessary to develop robust and reliable approaches to identify damage status to set an early warning threshold before a disaster occurs. The SHM of civil infrastructures, such as bridges and dams, is crucial to the safe operation and the longevity of the system [8, 9]. Significant developments of SHM of civil structures have originated from major construction projects, such as large dams and long-span cable-supported bridges. A regular inspection of dams became a legal requirement in the UK after the failure of a 30 m embankment dam claimed the lives of 254 people near Sheffield, UK in 1864 [10]. The traditional procedure for the evaluation of the structural health condition of dams is through visual inspection [11]. Visual inspections have some shortcomings such as significant labor demanding and inaccessible critical locations. The problems of visual inspections can be addressed with the field tests, which are conducted to monitor the dynamic and static characteristics of structures. For a large dam structure, such as the Fei-Tsui dam, it is a challenging task to excite the structure vibration. The vibration measurement data are obtained only when an earthquake happens. The use of the static deformation measurement can be an alternative way to continuously monitor the structural health of a dam [12]. This paper presents an investigation of SHM of Fei-Tsui dam with the use of the daily measured static deformations at various locations. Based on the results of the previous study [1, 13], the water level and temperature are the two most important variables affecting static deformation. The examination in this paper is based on a modeling technique [13], where the static deformation is modeled as a function of the measured water level and temperature. The results demonstrate that the identified model, based on the proposed technique, not only well represents the experimental data but also gives the precise prediction of the long-term deformation for SHM. The goal of this research is to develop a reliable and effective technique to identify any possible abnormality happened to Fei-Tsui dam for safe operation and failure prevention. J.-S. Lew( ) Center of Excellence in Information Systems, Tennessee State University, Nashville, TN 37209, USA e-mail: lew@coe.tsuniv.edu © The Society for Experimental Mechanics, Inc. 2015 C. Niezrecki (ed.), Structural Health Monitoring and Damage Detection, Volume 7, Conference Proceedings of the Society for Experimental Mechanics Series, DOI 10.1007/978-3-319-15230-1_8 67
RkJQdWJsaXNoZXIy MTMzNzEzMQ==