Ultrasonic propagation velocity across wood fiber direction was measured in wooden bridges in order to investigate the possibility of nondestructive deterioration diagnosis of wooden bridges. The measurements were carried out for three different types of wooden bridges. The periodical measurement was also made for one of them to investigate its secular change. The results were : (1) The histogr...

In this study, a nondestructive ring-shaped laser ultrasonic method with thermoelastic excitation regime was used to determine the grain size of metal materials. This proposed in order evaluate quality fast online manner. Normally, is detect ablation regime. The excites high energy longitudinal waves but causes damage surface To achieve strict testing, work. converted from circular collimated b...

The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulu...

The objective of this study was to examine the potential of ultrasonic velocity as a rapid and nondestructive method to predict the dimensional stability of oak (Quercus petraea (Mattuschka) Lieblein) and chestnut (Castanea sativa Mill.) that are commonly used in flooring industry. Ultrasonic velocity, specific gravity, and radial, tangential and volumetric shrinkages were measured on seventy-f...

Ultrasonic testing (UT) has been used for nondestructive evaluation (NDE) of materials for more than half a century. A number of NDE techniques have been developed and specifi standards have been created for the UT applications in different areas of engineering. UT has two main goals related to inspection of solid objects, firstl , detection and characterization of material discontinuities (fl ...

Using wavelet transform (WT) for increasing signal-to-noise ratio (SNR) of discrete-time signals corrupted by additive noise is explained and compared with some other techniques (averaging, frequency filtration, correlation). Signal processing for de-noising is applied to basic periodical signals and repeated transients (in nondestructive ultrasonic testing of welds, where presence of flaws sho...

A concrete bridge over Interstate 70 east of Denver, Colorado was impacted by a fork lift being transported by a truck moving at a speed of approximately 75 mph. The forklift impacted the east face of the prestressed concrete I-beam bridge girder, resulting in severe cracking and concrete spalling on both sides of the eastmost girder. Polymer-modified repair mortar was used to repair spalled ar...