Program
Civil Engineering
College
Engineering
Student Level
Doctoral
Start Date
7-11-2018 3:00 PM
End Date
7-11-2018 4:00 PM
Abstract
Ultrasonic monitoring in cementitious materials is challenging due to the high degree of attenuation. In wellbore environments, monitoring becomes more challenging due to inaccessibility. Meta materials, also known as acoustic bandgap materials, exhibit an interesting feature of forbidding the propagation of elastic/sound waves and isolate vibration in a certain frequency band. Traditionally, acoustic bandgap materials are developed with inclusions such as tin, aluminum, gold, steel in a polymer matrix. In this study, we present the development of three-dimensional cementitious sensors capable of exhibiting stopbands in the acoustic transmission spectra using carbon nanotubes. Relatively wide stopbands were engineered using Floquet-Bloch periodic conditions and computational simulations were conducted with cementitious matrix incorporating carbon nanotubes inclusions. The result of our investigations demonstrates, for the first time, the possibility of using cementitious sensors with wide acoustic stopbands in cementitious media. Based on the above simulations, a new sensor is designed and fabricated and the methods of making the sensor is presented. The new cementitious sensors are subjected to a frequency sweep and the transmission spectra is observed demonstrating the possible monitoring behavior of cement casing in wellbore service environments.
Included in
Engineering Physics Commons, Nanoscience and Nanotechnology Commons, Polymer and Organic Materials Commons, Structural Engineering Commons, Structural Materials Commons
Cementitious Sensors Exhibiting Stopbands in Acoustic Transmission Spectra
Ultrasonic monitoring in cementitious materials is challenging due to the high degree of attenuation. In wellbore environments, monitoring becomes more challenging due to inaccessibility. Meta materials, also known as acoustic bandgap materials, exhibit an interesting feature of forbidding the propagation of elastic/sound waves and isolate vibration in a certain frequency band. Traditionally, acoustic bandgap materials are developed with inclusions such as tin, aluminum, gold, steel in a polymer matrix. In this study, we present the development of three-dimensional cementitious sensors capable of exhibiting stopbands in the acoustic transmission spectra using carbon nanotubes. Relatively wide stopbands were engineered using Floquet-Bloch periodic conditions and computational simulations were conducted with cementitious matrix incorporating carbon nanotubes inclusions. The result of our investigations demonstrates, for the first time, the possibility of using cementitious sensors with wide acoustic stopbands in cementitious media. Based on the above simulations, a new sensor is designed and fabricated and the methods of making the sensor is presented. The new cementitious sensors are subjected to a frequency sweep and the transmission spectra is observed demonstrating the possible monitoring behavior of cement casing in wellbore service environments.
