0000000000022852
AUTHOR
La Malfa Ribolla E.
On the FE·Meshless computational homogenization for the analysis of two-dimensional heterogeneous periodic materials
Over the last few years, substantial progresses have been made in the two-scales com- putational homogenization. This method is essentially based on the assessment of the macroscopic constitutive behavior of heterogeneous materials through the boundary value problem (BVP) of a statistically representative volume element, named as unit cell (UC). In this framework, the first-order method has now matured to a standard tool and several extensions have been addressed in the literature [1, 2]. In the present study, a first-order homogenization scheme based on a discontinuous- continuous approach is presented. At the mesoscopic level the formation and propagation of fracture is modeled employing …
FRP-Substrate bonding quality investigation making use of ultrasonic waves
Fiber reinforced polymer (FRP) composite systems are widely used to repair structurally deficient constructions thanks to their good immunity to corrosion, low weight and excellent mechanical properties. The quality of the FRP-substrate interface bond is a crucial parameter affecting the performance of retrofitted structures. In this framework, ultrasonic testing could be used to assess the quality of the bonding [1-2]. In the case of FRP laminates adhesively bonded to roughly inhomogeneous materials, such as concrete, high scattering attenuation occurs due to the presence of heterogeneities. The concrete behaves almost like a perfect absorber generating a considerable number of short-space…
Solitary Waves for the Assessment of Thermal Stress and Neutral Temperature in Slender Structures
Slender columns and continuous welded rails subjected to compressive stress are common in many civil structures. The rapid in-situ measurement of this stress may be of interest to prevent structural anomalies such as buckling. In this article, the authors describe the coupling mechanism between highly nonlinear solitary waves (HNSWs) propagating along an L-shaped granular system and a beam in contact with the granular medium. The aim is the evaluation of HNSWs as a tool to measure stress in thermally loaded structures and to estimate the neutral temperature, i.e. the temperature at which this stress is null. The authors investigated numerically and experimentally one chain of spherical part…