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Floor vibrations caused by human activities is an issue to consider mainly caused by new construction tendencies towards longer, lighter and less damped composite floor systems. Furthermore, the removal of full height partitions and heavy furniture elements have also contributed to reduce both, mass and damping, increasing the potential for annoying floor vibration. As a result, Vibration Serviceability Limit State has become the main limit state to overcome at the design stage. The response of dynamically loaded structures is especially dependable on structures dissipation capacity, commonly modelled as structural damping. This inverse relation between damping and dynamic response behaves exponentially. That is why increasing the structural damping in low damped structures from the design stage, is the most efficient way to face the vibration issue. This is the main idea behind the concept of Damping-Based Design. In this paper, a highly-damped composite floor system is achieved through constraining an elastomer sandwiched layer between the concrete slab and the steel beam. Therefore, additional energy dissipation is provided through viscoelastic shear deformation between concrete and steel, increasing the overall damping of the structure, and thus, enhancing its dynamic response. In this context, the authors have developed a simplified and engineering-based FE model, in a fully-extended and commercial software for structural analysis as SOFiSTiK. Hence, a new simple engineering approach has been developed for easily assessing the enhanced performance of these systems, contrasting the limited results provided by other authors about this topic. The authors would like to acknowledge the financial support provided by the Spanish Ministry of Science, Innovation and Universities through the project SEED-SD (RTI2018-099639-B-I00). Carlos M. C. Renedo would like to thank Universidad Politécnica de Madrid for the financial support through a PhD research grant. Finally, Iván M. Díaz would like to acknowledge the financial support provided by Fundación José Entrecanales Ibarra to carry out a Research Stay at University of Exeter.

This paper describes the experimental and numerical lateral vibration assessment of La Paz footbridge (LPF) as part of a research project of pedestrian structures located in Madrid. LPF is a cable-stayed structure with main span of 85m and total length of 127.8m. A preliminary analysis predicted a first lateral mode close to 0.9Hz, which is within the critical range and, consequently, a further analysis was required. The numerical assessment was performed in the frequency domain and the pedestrian action was defined using the HIVOSS guide. The experimental evaluation consisted in both the modal testing of the structure to validate the numerical model, and interaction pedestrian tests. The numerical model is in accordance with the tests and thus the footbridge dynamics is accurately determined. However, the interaction pedestrian tests are not sufficient to evaluate the LPF performance under dense traffic conditions. The authors acknowledge the financial support provided by the Spanish Ministry of Science, Innovation and Universities through the project SEED-SD (RTI2018-099639-B-I00).

Human loading may induce significant vibrations in some types of structures such as long-span floor slabs or light-weight pedestrian bridges, affecting their vibration serviceability limit state. In many cases, this limit state is not taken into account properly within the structural design process or this is not fulfilled during its life span. Finding the source of the problem may be an awkward task and a monitoring campaign to check this behavior may be expensive. In this paper, a dynamic analysis mobile phone tool named DynApp has been developed in Android. This allows the user to make in one go the measurements and the identification of the resonant frequencies of the structure avoiding engineers to carry out dynamic analysis of structure with tedious setups (accelerometers, long cables, acquisition systems, power suppliers, etc.) and difficult-to-use specialized software. DynApp guides practitioners/engineers easily through frequency and time domain tests and helps them to make a decision shortly about the serviceability Comfort Class. This tool is also used in master clases for teaching the background content. The authors acknowledge the Educational Innovation Project Técnicas Experimentales de análisis dinámico: caracterización dinámica y cancelación de vibraciones (IE1819.0407). They also want to acknowledge the master students for using and check DynApp. The authors would like to acknowledge the financial support provided by the Spanish Ministry of Science, Innovation and Universities through the project SEED-SD (RTI2018-099639-B-I00). Finally, Carlos M. Renedo would like to thank Universidad Politécnica de Madrid for the financial support through a PhD research grant.

The authors have demonstrated that human-induced vibration can be controlled with passive, active and semi active inertial controllers working as a single-input single-output or multi-input multi output configuration. This paper describes a general methodology for designing inertial controller for human-induced vibration that can meet passive, active and semi-active controller and both linear and nonlinear modalities. That is, a feedback-based methodology has been developed in which the control system is separated from the structure in order to be designed as a feedback controller, designing both location and control parameters. The structure excites an inertial system placed on it and this system, placed on the structure, applies forces to it. Thus, the control forces of the inertial mass controller can be configured into the loop to optimize the design parameters. A numerical example is presented to show the potential of the method. The authors acknowledge the financial support provided by the Spanish Ministry of Science, Innovation and Universities through the project SEED-SD (RTI2018-099639-B-I00). Dr. Iván M. Díaz would like to acknowledge the financial support provided by Fundación José Entrecanales Ibarra to carry out a Research Stay at University of Exeter.