Ultrasonic guided waves have been used in testing of such an elongated object as pipe. Its sensitivity and distance resolution, however, have been limited by velocity dispersion and interference of numerous propagation modes of guided waves. Trapped energy mode of vibration of thickness shear waves in a quartz plate has been widely used in frequency control and selection due to its high Q and l...

the seismic performance of hybrid braces composed of steel and shape memory alloy (sma) was investigated in this paper. six types of hybrid braces were used, constituted by sma content of 0, 20, 40, 60, 80, and 100%. a nonlinear dynamic analysis was performed under el centro earthquake records, with the maximum acceleration of 0.6g and 0.9g. our results showed that the seismic performance, i.e....

One of the most common and challenging problems in seismology is the prediction of source-receiver paths taken by seismic energy in the presence of lateral variations in wavespeed. The solution to this problem is required in many applications that exploit the high frequency component of seismic records, such as body wave tomography, migration of reflection data and earthquake relocation. The pr...

[1] We examine the work energy budget of actively deforming fault systems in order to develop a means of examining the systemic behavior of complex fault networks. Work done in the deformation of a faulted area consists of five components: (1) work done against gravity in uplift of topography (Wgrav); (2) internal energy of the strained host rock (Wint); (3) work done resisting friction during ...

The geological materials in Earth's lowermost mantle control the characteristics and interpretation of seismic ultra-low velocity zones at the base of the core-mantle boundary. Partial melting of the bulk lower mantle is often advocated as the cause, but this does not explain the nonubiquitous character of these regional seismic features. We explored the melting properties of mid-oceanic ridge ...

The seismic performance of hybrid braces composed of steel and shape memory alloy (SMA) was investigated in this paper. Six types of hybrid braces were used, constituted by SMA content of 0, 20, 40, 60, 80, and 100%. A nonlinear dynamic analysis was performed under El Centro earthquake records, with the maximum acceleration of 0.6g and 0.9g. Our results showed that the seismic performance, i.e....