Prof. Yi-Lung Mo Profile

Prof. Yi-Lung Mo

at Univ of Houston

SPIE Involvement:

Author

Publications (3)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 9 April 2010 Paper

Health monitoring of concrete piles using piezoceramic-based smart aggregates

Gangbing Song, Haichang Gu, Y. Mo, Ruoling Wang

Proceedings Volume 7650, 76500X (2010) https://doi.org/10.1117/12.847827

KEYWORDS: Sensors, Actuators, Ferroelectric materials, Transducers, Wave propagation, Acoustics, Signal attenuation, Damage detection, Wavelets, Optical fibers

Read Abstract +

Concrete piles are widely used in the construction of civil infrastructures and it is important to perform the health monitoring of concrete piles for safety purposes. In this paper, a piezoceramic-based innovative approach is proposed for the damage detection and health monitoring of concrete piles. A multi-functional piezoceramic-based transducer device, the smart aggregate, is developed for health monitoring purposes. An active-sensing network is formed by embedding the proposed smart aggregates at the pre-determined locations in the concrete piles before casting. In the proposed approach, one smart aggregate is used as an actuator to excite the desired waves and the other distributed smart aggregates are used as sensors to detect the wave responses. An energy distribution vector is formed based on the wavelet-packet analysis results of sensor signals. A damage index is formed by comparing the difference between the energy distribution vectors of the health concrete pile and that of the damaged concrete pile. To verify the effectiveness of the proposed approach, two concrete piles instrumented with smart aggregates are used as testing objects. One concrete pile is intact and the other has a man-made crack in the middle of the pile. Experimental results show that the there are differences between the energy distribution vectors of the damaged pile and that of the intact pile due to the existence of the crack. The proposed method has the potential to be applied to perform automated integrity inspections for new piles and for the long-term health monitoring of piles in services.

Proceedings Article | 11 April 2006 Paper

Effect of SMA bars on cyclic behaviour of low-rise shear walls

W. I. Liao, E. Effendy, G. Song, Y. L. Mo, T. T. C. Hsu, C. H. Loh

Proceedings Volume 6174, 61743H (2006) https://doi.org/10.1117/12.657733

KEYWORDS: Shape memory alloys, Molybdenum, Earthquakes, Civil engineering, Mechanical engineering, Roads, Smart materials, Sensors, Smart structures, Aerospace engineering

Read Abstract +

Past RC panel tests performed at the University of Houston show that reinforced concrete membrane elements under reversed cyclic loading have much greater ductility when steel bars are provided in the direction of principal tensile stress. In order to improve the ductility of low-rise shear walls under earthquake loading, high seismic performance shear walls have been proposed to have steel bars in the same direction as the tensile principal direction of applied stresses in the critical region of shear walls. This paper presents the results of reversed cyclic tests on three low-rise shear walls with SMA bars. The height, width, and thickness of the designed shear walls are 1.0 m, 2.0 m, and 0.12 m, respectively. SMA bars are provided in the directions of 27 degrees to the horizontal that are in the diagonal direction. The reinforcing bars of the shear walls are in vertical and horizontal directions. The ratios of both SMA and reinforcing bars are 0.24%. The main parameter used in the study is the type of SMA bar, namely Superelastic and Martensite SMA bars. The test results from the walls with SMA bars are also compared to a conventional wall without SMA bars. Test results also show that the maximum shear strengths of the tested walls are affected by the SMA bars. It was found that the shear wall with Martensite SMA bars has greater residual displacement. In contrast, the shear wall with superelastic SMA bars has less residual displacement. At the ultimate state, one of the four superelastic SMA bars buckled, resulting in less energy dissipation capacity than the expected value. Preventing buckling of SMA bars is the research focus in the near future.

Proceedings Article | 16 March 2006 Paper

Early age strength monitoring of concrete structures using embedded smart piezoelectric transducers

H. Gu, G. Song, H. Dhonde, Y. L. Mo, S. Yan

Proceedings Volume 6179, 61790H (2006) https://doi.org/10.1117/12.668017

KEYWORDS: Fuzzy systems, Fuzzy logic, Sensors, Cements, Transducers, Ultrasonics, Associative arrays, Capacitance, Nondestructive evaluation, Actuators

Read Abstract +

It is important to conduct early age strength monitoring of concrete structures because it will help speed up construction. Piezoelectric-based strength monitoring method provides an innovative experimental approach to conduct concrete strength monitoring at early ages. In the presented paper, piezoelectric transducers were embedded into the concrete specimen during casting. The development of strength of concrete structures was monitored by observing the development of harmonic amplitude from the embedded piezoelectric sensor at early ages. From the experimental results, the amplitude of the harmonic response decreased with the increment of the concrete strength. The amplitude of the harmonic response from piezoelectric sensor dropped rapidly for the first week and continued to drop slowly as hydration proceeded which matches the development of the concrete strength at early ages. Concrete is heterogeneous and anisotropic which makes it difficult to be mathematically analyzed. Fuzzy logic has the advantage to conduct analysis without requiring a mathematical model. In this paper, a fuzzy logic system was trained to correlate the harmonic amplitude with the concrete strength based on the experimental data. The concrete strength estimated by the trained fuzzy correlation system matches the experimental strength data. The proposed piezoelectric-based monitoring method has the potential to be applied to strength monitoring of concrete structures at early ages.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years