Impact of selected sources of transport vibrations on the perception of vibrations by people in buildings

Vibrations propagating through the soil into the building can not only be harmful to the building structure or cause its accelerated wear, but can also effect on the vibrational comfort in the rooms. They can also be annoying for residents and building users, and in extreme cases can lead to sleep disorders, headaches and neurotic conditions. Especially vibrations from the low frequency range from 5 to 25 Hz are undesirable, because there are resonance frequencies of human internal organs in this frequency range. The human perception of vibrations in buildings, despite many researches made in the past, despite standards and requirements in this area, is still a topic not fully understood mainly due to the subjective nature of the perception of vibrations by various people. It is widely known that the type of transport vibration source has an impact on human perception. Vibrations generated by above-ground sources are more felt on the upper floors as opposed to vibrations generated from the underground. In this paper three types of transport vibrations are analyzed on one chosen building located in Warsaw. Human perception of vibration is evaluated according to two methods: root mean squared (RMS) and vibration dose value (VDV)

Human perception of vibrations according different assessment methods

Human perception of vibration could be the basic parameter in designing new buildings subjected to different type of transport vibrations. Humans are more sensitive for vibrations then building structure. In an increasingly urbanized city centres people are exposed to vibrations from different transport sources such as: tramways, railways, heavy truck traffic or subway especially when considered shallow underground. The aim of this paper is to investigate the use of two different evaluation methods of human perception of vibrations. Methods chosen for evaluation are: the basic root mean squared (RMS) method and the additional method of evaluation vibration dose value (VDV). The building chosen for analysis is subjected to three different vibration sources: tram, heavy truck and subway passages. It is located in Warsaw where is a shallow underground which could have significant influence on human response to vibrations because vibrations from this kind of source is more perceptible on lower floors. That is why measurement points were located in the middle of the floor on the ground floor and on the top floor. The registered signal from the three different sources of vibration was analysed according to RMS and VDV procedure included in ISO standard. RMS and VDV methods were compared with each other

Influence of crest factor on evaluation of human perception of traffic vibration

In this article many vibrational signals of different value of crest factor are investigated. Evaluation of human perception of vibration is made with use of two different method of evaluation: basic RMS method and vibration dose value method (VDV), which is one of additional method mostly used for peak signals. Analysis of influence of crest factor value on evaluation of human response to vibration is made

Analysis of subsoil modeling influence on dynamic characteristics of reinforced concrete building

The paper is devoted to issues related to creation of subsoil models. At the beginning of the paper, the model of the building chosen for the analysis was described. The procedures for calculation of different models of the subsoil were also described. The final part of this paper presents results of the analysis of natural frequencies of reinforced concrete building with regard to the different models of the interaction between subsoil and the structure, and the conclusions drawn from this analysis are also presented

Analysis of the influence of reinforced concrete beam-and-slab floor forming on dynamic characteristics of a building

A dynamic response of structures determine its dynamic characteristics, i.e. the natural frequency, the corresponding figures of vibration and damping coefficient. Designing of a building in terms of dynamics lets us interfere in its stiffness and mass which allows the derivation of the structure of the resonance zone early in the design stage. It is known that the larger the value of the natural frequency the greater the stiffness of the whole structure. The article examined how the natural frequencies of the objectchange under the influence of adjustments in the development of the floor model. The main purpose of the analysis carried out in the article was to determine the relationship between stiffness and mass matrices and the results of the modal analysis of the chosen structure. The article hypothesized that the natural frequency is inversely proportional to the mass of the floor raised to a suitable exponent. A formula derived from this relationship has been verified on a number of variants of the building model made in the program for numerical calculation Dlubal

Stress distribution in masonry infills connected with stiff and flexible interface

Masonry infills are largely used in RC structures for various purposes, and in seismic zones, they are also preferred for providing earthquake resistant systems. However, due to the rigid connection between infills and RC frames, these systems are vulnerable when large deformations are demanded. Cyclic loads that are occurring during seismic excitations cause stress concentration level to increase, particularly in frame-infill contact zones. As a result of stress increment, infill panels get weaker in terms of both in-plane and out-of-plane resistance. These drawbacks cause loss of lives and properties, thus affecting governments and societies adversely. In order to overcome this obstacle, an innovative solution is proposed which uses flexible polymers (Polyurethane PM) as joint elements for protecting the structural elements. The research is focused on numerical analyses of three types of frames with masonry infills, which are excited through both in-plane and out-of-plane directions by different earthquake records. Infill walls are connected to the frames in three manners: stiffly (classical approach), with flexible joints at 3-boundaries and with flexible joints at 4-boundaries. Differences in calculated stress distribution as well as some other linear and non-linear results are presented and discussed. The primary results give promising outcomes that this new method might be used in seismic zones for protecting structures

Influence of different types of trams on human perception of vibrations in buildings

In an increasingly urbanized areas transport vibration source are closer and closer to the receiver which is a building. At the same time residents requirements for comfort in rooms are higher. In this paper influence of transport vibrations from various types of trams on human perception was tested and analysed. Measurements were made in Cracow on 11 buildings located near tramway. Human perception were investigated according to ISO and Polish standard. Basic RMS method and additional VDV method were applied because of high crest factor of recorded signal. Results of both methods were compared

Protection of historic buildings against environmental pollution of vibrations

Historic buildings in Poland are largely neglected objects that small percentage is preserved in its original form. Unrelenting in the case of historic buildings is a time that brings with it the natural processes of aging of buildings, but also the history of the object which is often marked by military conflicts, fires or even incompetently carried out reconstruction. Nowadays historic buildings are also destroyed by the rapid development of infrastructure and residential construction. This development could lead to changes of water in the soil, make changes in the geologic al structure or cause exposure of the historic building to the new influences (eg. traffic vibrations), to which building has not been subjected so far. Vibrations are often omitted in environmental issues, although the protection against noise and vibration has its place in the Law on Environmental Protection. This article presents the methodology for the measurement and interpretation of vibration influence on historic buildings and the assessment methods of technical condition of historic building on the example of dynamic measurements made on St. Nicholas Church in Krakow. The importance of well-done crack-by-crack documentation and characterization of damages based on damage index is shown. Difficulties that can be encountered when determining the causes of technical condition of historic buildings are also shown. Based on the example of the Church in the article are also given the possible protection solutions of historic structures from vibrations

Influence of different types of trams on human perception of vibrations in buildings

In an increasingly urbanized areas transport vibration source are closer and closer to the receiver which is a building. At the same time residents requirements for comfort in rooms are higher. In this paper influence of transport vibrations from various types of trams on human perception was tested and analysed. Measurements were made in Cracow on 11 buildings located near tramway. Human perception were investigated according to ISO and Polish standard. Basic RMS method and additional VDV method were applied because of high crest factor of recorded signal. Results of both methods were compared

Transmission of transport vibrations from the ground to the building - case study

Transport vibrations are transmitted from the ground the foundations and building walls to the building and received by its construction and by people in the buildings. During the vibration of buildings, inertia forces generate an additional (apart from the static one) loading of the structure. In the diagnosis and design of buildings, these forces are taken into account by analyzing the requirements for stiffness and strength of the building structure. Exceedance of these requirements may lead to accelerated wear and even structural damages of the building. In this paper a simple relationship between ground and building vibration was made. The building chosen for analysis is light-weight wooden building located close to Cracow near Zakopianka road. What is worth noting that building is so called passive building. The excitation which was simulated on the dynamical polygon was car (bus) and truck lorry passages. The sensors were accelerations in three orthogonal directions, one sensor was placed about 2.5 m far from the building and the second on the foundation wall. The different types of excitation were compared and the conclusion from the analysis was made