In recent years, the use of new and unique building materials to achieve green building goals has attracted a lot of attention. Optical fiber light-transmitting concrete (LTC) makes it possible for light to pass through concrete. Its ornamental value and excellent light transmission have received much attention from scholars. However, the application of optical fiber LTC in the construction industry has not yet been promoted due to the tedious preparation process and insufficient research on its mechanical properties and durability. This paper reviews the research results of optical fiber LTC in terms of product preparation, light transmission, mechanical properties, durability, and microstructures. The light transmission of optical fiber LTCs is positively correlated with fiber content and negatively correlated with fiber diameter and fiber spacing. However, how the combination of these factors affects LTC transmittance remains to be investigated. In addition to fiber parameters, cement matrix properties and other environmental factors (light intensity, incidence angle, and aging) should also be considered to explore the suitability of LTC. The fiber–matrix interface bond strength needs further investigation and efforts should be made to improve it. This paper also summarizes the future challenges and research directions of optical fiber LTC, which is expected to provide guidance for the application of optical fiber LTC. It is anticipated that fiber-optic LTC will be promoted as a new building material.

Ultrasonic guided wave (UGW) inspection is an emerging non-destructive testing(NDT) technique for rail flaw detection, where weak UGW signals under strong noise backgrounds are difficult to detect. In this study, a UGW signal identification model based on a chaotic oscillator is established. The approach integrates the UGW response into the critical state of the Duffing system to serve as a disturbance control variable. By evaluating the system’s motion state before and after introducing the UGW response, identification of UGW signals can be realized. Thus, the parameters defining the critical state of Duffing oscillators are determined by $K_e$. Moreover, an electromagnetic transducer was specifically devised to enable unidirectional excitation for UGWs targeted at both the rail base and rail head. Experimental studies showed that the proposed methodology effectively detected and located a 0.46 mm notch at the rail base and a 1.78 mm notch at the rail head. Furthermore, $K_e$ was directly proportional to the notch size, which could be used as a quantitative index to characterize the rail flaw.

The identification of a blood vessel’s elastic properties by an ultrasonic guided wave mainly depends on the accurate propagation characteristics, which are obtained by solving the problem of elastic mechanics based on a thin-plate model. However, this method cannot accurately predict the characteristics for low frequencies. Since blood vessels are of a tubular structure, a hollow-cylinder model, constructed to model blood vessels, is proposed in this paper. Based on this model, the propagation characteristics and dispersion curves of the ultrasonic guided wave propagating along the axial direction are studied by expanding the state equation using Legendre polynomials. A detailed comparison between the results of the proposed model and the thin-layer-based model is presented. It is shown that the dispersion curves of the L (0,1) modes, calculated by the two different models, are a match for high frequencies but differ for low frequencies. The dispersion curve of the L (0,1) mode calculated by the proposed model is in good agreement with the results of the reported experiments. Then, the relationship between the propagation characteristics of ultrasonic guided waves and Young’s modulus is studied. It is discovered that the phase velocity and group velocity are significantly affected by Young’s modulus close to the cutoff frequency, which has important implications for the selection of the detection frequency to the characteristic parameter of vascular.

This paper presented a circumferential semianalytical finite element method (CSAFEM) to examine the distinctive wave characteristics of circumferential guided waves (CGWs) in anisotropic hollow cylinders. This methodology models the radial displacement using finite elements while expanding the circumferential displacements as harmonic exponentials. A weak‐form wave motion equation in an anisotropic hollow cylinder is formulated using Hamilton’s principle. Phase velocity curves are introduced to visualize the influence of anisotropy and the ratio of diameter to wall thickness (OD/WT) on wave propagation. The CSAFEM results are validated against analytical solutions for CGWs in isotropic hollow cylinders, achieving excellent agreement. This methodology extends to materials with complex symmetries, including triclinic and orthorhombic types. Numerical examples demonstrate that the OD/WT ratio significantly influences the phase velocity spectra of CGWs in the cylinders. In addition, the study explores the relationship between a planar structure and an annulus as the OD/WT ratio approaches infinity, highlighting unique wave phenomena specific to curved waveguides. This unique new mode appears at the initiation of the CA0 mode because the inner surface does not support the propagation of surface waves. This phenomenon is observed in isotropic, orthotropic, and triclinic materials.