Abstracts Archive

Large amplitude vibrations in slender structures tend to introduce nonlinearities in the structural response due to coupled bending and membrane stretching effect. This is generally observed as a hardening or a softening type nonlinearity which results in amplitude dependent shifts in modal frequenc...

Increasing the damping properties of a structure while limiting the addition of mass is a challenging task. Originally developed for their acoustic absorption capabilities, microperforated plates (MPP) are simple devices that can feature additional viscous damping at low frequencies. Dissipation ari...

In order to design effective energy-absorbing shields made of modern composite materials (e.g., fibrous composite panels), it is necessary to use deformable materials whose important feature is the largest possible dissipation of impact energy. Rheological properties of these materials differ signif...

Nonlinearities significantly limit the size and complexity of numerical models. The present work presents a general method to simulate kinematic nonlinear structures more efficiently. An efficient basis formulation that increases the number of basis vectors without increasing the number of unknown b...

On the 17th of October 2021 a grandstand of the Goffert stadium partially collapsed while a crowd was jumping on it. Forensic engineering concluded that the main reason of the collapse was that the load of a jumping crowd exceeded the design load of 4 kN/m2, as specified in the Eurocode. The actual ...

In this paper, the nonlinear aeroelastic system behaviour of a typical section airfoil with two degrees of freedom is investigated. The aim of this work is to characterize the nonlinear dynamics and mapping the regions of limit cycle oscillations (LCO). Firstly, a previous numerical model [1] is sim...

Frictional joints are present in a plethora of applications and fields, such as the aerospace, automotive, and building industries. Therefore, an ever-important challenge in the analysis of engineering systems is the understanding of friction damping in structural dynamics. Due to its nonlinear and ...

This research examines the influence of the two main types of earthquake mechanisms (i.e., subduction and crustal) on the seismic response of steel moment frames (SMFs). Nonlinear time history analyses are conducted on five archetypes SMFs (varying in height) using two suites of 500 carefully select...

An approach for the identification of discontinuous and nonsmooth nonlinear forces, as those generated by frictional contacts, in mechanical systems that can be approximated by a single-degree-of-freedom model is presented. To handle the sharp variations and multiple motion regimes introduced by the...

A novel type of structure-dependent integration methods has been developed for time integra-tion and pseudo-dynamic testing. The feasibility of this type of integration methods has been numerically affirmed by numerical tests and experimentally validated by pseudo-dynamic test-ing. It is generally r...

It is remarkable that trees with high slenderness ratios are able to survive regular strong wind events. This phenomenon is motivating the exploration of the inherent vibration mitigation mechanisms of trees. This study examines the role of trees’ hierarchical branching architecture on their modal...

The dynamic behaviour of a freestanding block rocking on a rigid base when subjected to a horizontal ground excitation is a classical problem of nonlinear dynamics that has drawn considerable attention. Despite the apparent structural simplicity, rocking motion is characterised by various nonlinear ...

Abstract—This paper defines the methodology of designing Control Room Buildings for Vapor cloud explosion (VCE). Intensity of blast forces has not been standardized. Companies have their own specifications based on internal research relying on the interpretation of damages suffered in real life sc...

This presentation discusses the basic concept and recent developments in the field of the intermodal targeted energy transfer (IMTET) - a novel suggestion for passive mitigation of mechanical and civil structures in conditions of blast and seismic excitations. This is achieved by introducing strateg...

The one of the authors proposed the causal hysteresis damping and the extended Rayleigh damping as damping models with low frequency dependence for damping ratio. The causal hysteretic model is based on the causality theory and past displacements are used in the calculation. The extended Rayleigh da...

In this paper, transverse and longitudinal vibrations and resonances in an elevator cable system induced by boundary excitations are studied. The dynamics can be described by an initial-boundary value problem for a (coupled system of) nonlinear wave-equation(s) on a relatively slowly time-varying sp...

The prediction of the so-called seismic site response (i.e., the response of the top soil layers induced by seismic waves) is important for designing structures in areas prone to earthquakes. For seismic loads that induce large soil strains, accounting for the nonlinear behaviour of the soil can be ...

In the area of passive vibration mitigation, nonlinear energy sinks (NESs) have been extensively studied. They are an alternative to traditional tuned mass-dampers as they can mitigate vibrations over larger frequency ranges while being efficient in both transient and stationary regimes presenting p...

Hyperloop is a new emerging transportation system that is in the development stage. Its design minimises the air resistance by having the vehicle travel inside a de-pressurised tube (near vacuum) and eliminates the wheel-rail contact friction by using an electro-magnetic levitation system (similar t...

Applying an oscillatory load is one of the most efficient ways to alter friction forces. Several theoretical and experimental studies on the influence of oscillatory loads on friction have been conducted, investigating the effect of both in-and out-of-plane oscillations for different tribological pa...

The non-linear dynamics of layered structures are highly dependent on the material and bonding between each layer; a lack of proper alignment, or delamination, could lead to deleterious outcomes including structural failure. Experiments on different types of thin-walled cylindrical shells have recen...

Identification and extraction of damage sensitive features is a crucial task for the health, serviceability, and lifetime assessment of civil and industrial structures. Within this framework, the vibration-based structural damage detection of nonlinear beams is herein accomplished using a convolutio...

Recent studies carried out in the literature have shown that the mechanical properties of bioinspired periodic composite materials can be strongly influenced by finite deformations effects leading to highly nonlinear static and dynamic behaviors at multiple length scales. For instance, microscopic a...

In this work, modelling of non-smooth dynamics of an Anti Stick–Slip Tool (ASST) is carried out. ASST is used to protect a drill-string from a severe form of torsional vibrations known as stick-slip. A drill string is an essential component of any downhole drilling process and it exhibits a highly...

In structural dynamics, it is well known that the motion of a single degree of freedom (SDOF) system with hysteresis subjected earthquake ground motions can be described by the equation m·a(t) + c·v(t) + H(x(t)) = -m·g(t) (plus the initial conditions v(0) and x(0)), where a(t), v(t), x(t), are th...

In this paper, we studied a vibration of a string. The string is attached to a fixed point on one end while on the other hand, the position of the contact point can vary along a smooth obstacle. By applying a boundary fixing transformation, we transform the problem from a linear problem with moving ...

The occurrence of moderate to high-intensity earthquakes in countries like Chile and New Zeeland, has shown damage to well-detailed reinforced concrete wall buildings designed according to seismic-resistant regulations, which leads to a questioning about the level of damage that would be expected, i...

In recent years there has been an increasing demand for housing in developing countries such as Colombia. Therefore, a significant number of mid-rise residential buildings with thin RC shear walls have been built for low-cost construction requirements. These buildings have been constructed in areas ...

Robot locomotion has become increasingly common to transport and assist humans in complex environments. Even though legged locomotion does not correspond to the most efficient transportation system, in some circumstances it is the only reasonable option to overcome obstacles, as stairs, or to move o...