Evaluation of the traffic impact on residential building

The paper presents an example of evaluation of the traffic impacts on the residential building. Residents noticed numerous damage to the building, which, in their opinion, were caused by the movement of trucks from the nearby transport base of agricultural equipment’s. The control seals have been glued on all cracks of the building and elements close to the road, in order to determine the damages propagation. The building and ground vibrations were established during the study. The vibration accelerations in the frequency function at the selected points of building were measured. Taking into account the dynamic impact scales (DIS), the vibration influences on the building were specified. Measurements of accelerations and vibration velocities inside a building were also conducted in order to determine the harmfulness of vibration in relation to the people. As a result of vibration accelerations test in different places of building, it was found that building is located in the first zone of the DIS, which vibrations are classified as imperceptible by the building. The harmfulness of occurring vibrations to the people staying in a residential building at the analysed road was also not found

Case study of a derecho wind storm on August 11-12, 2017 in Poland: part one

Windstorms belong to the most costly natural threats in Poland. On August 11-12, 2017, a strong thunderstorm happened which resulted in a catastrophic damage in three provinces: Wielkopolskie, Kujawsko-Pomorskie, and Pomorskie. This disaster has resulted in the death of 6 people, injuries to several dozen people, and enormous property losses including approximately 16,000 residential, utility and public buildings, 80,000 hectares of forest area, 67,000 hectares of agricultural crops, in excess of 300 overhead power line poles, and over 200 cables were downed. The trees felled by the wind blocked and partially damaged local and municipal roads over a length of about 1100 km. Over 500,000 consumers were deprived of electricity at the peak of the disaster. The purpose of this paper is to describe, analyse, and learn from such a dangerous extreme weather event. In order to achieve this, a cause of the thunderstorm, its important meteorological data, the severity of damage to buildings, civil infrastructure and environment, processes of damage surveys, ideas for reconstruction and removing of all damage, financial assistance from the central government, local authorities, and public collections were studied for better preparation of all services and people for mitigation of the effects of a natural disaster which may happen in the future. An example of a building with improved stiffness as the solution for better resistance of wind forces is presented

Evaluation of the traffic impact on residential building

The paper presents an example of evaluation of the traffic impacts on the residential building. Residents noticed numerous damage to the building, which, in their opinion, were caused by the movement of trucks from the nearby transport base of agricultural equipment’s. The control seals have been glued on all cracks of the building and elements close to the road, in order to determine the damages propagation. The building and ground vibrations were established during the study. The vibration accelerations in the frequency function at the selected points of building were measured. Taking into account the dynamic impact scales (DIS), the vibration influences on the building were specified. Measurements of accelerations and vibration velocities inside a building were also conducted in order to determine the harmfulness of vibration in relation to the people. As a result of vibration accelerations test in different places of building, it was found that building is located in the first zone of the DIS, which vibrations are classified as imperceptible by the building. The harmfulness of occurring vibrations to the people staying in a residential building at the analysed road was also not found

Application of Rotation Rate Sensors in Modal and Vibration Analyses of Reinforced Concrete Beams

The recent rapid development of rotation rate sensor technology opens new opportunities for their application in more and more fields. In this paper, the potential of rotational sensors for the modal analysis of full-scale civil engineering structural elements is experimentally examined. For this purpose, vibrations of two 6-m long beams made of ultra-high performance concrete (UHPC) were measured using microelectromechanical system (MEMS) rotation rate sensors. The beams were excited to vibrations using an impact hammer and a dynamic vibration exciter. The results of the experiment show that by using rotation rate sensors, one can directly obtain derivatives of mode shapes and deflection shapes. These derivatives of mode shapes, often called “rotational modes”, bring more information regarding possible local stiffness variations than the traditional transversal and deflection mode shapes, so their extraction during structural health monitoring is particularly useful. Previously, the rotational modes could only be obtained indirectly (e.g., by central difference approximation). Here, with the application of rotation rate sensors, one can obtain rotational modes and deflection shapes with a higher precision. Furthermore, the average strain rate and dynamic strain were acquired using the rotation rate sensors. The laboratory experiments demonstrated that rotation rate sensors were matured enough to be used in the monitoring and modal analyses of full-scale civil engineering elements (e.g., reinforced concrete beams)

Review of the Usefulness of Various Rotational Seismometers with Laboratory Results of Fibre-Optic Ones Tested for Engineering Applications

Starting with descriptions of rotational seismology, areas of interest and historical field measurements, the fundamental requirements for rotational seismometers for seismological and engineering application are formulated. On the above basis, a review of all existing rotational seismometers is presented with a description of the principles of their operation as well as possibilities to fulfill formulated requirements. This review includes mechanical, acoustical, electrochemical and optical devices and shows that the last of these types are the most promising. It is shown that optical rotational seismometer based on the ring-laser gyroscope concept is the best for seismological applications, whereas systems based on fiber-optic gyroscopes demonstrate parameters which are also required for engineering applications. Laboratory results of the Fibre-Optic System for Rotational Events & Phenomena Monitoring using a small 1-D shaking table modified to generate rotational excitations are presented. The harmonic and time-history tests demonstrate its usefulness for recording rotational motions with rates up to 0.25 rad/s

Rotation, Strain, and Translation Sensors Performance Tests with Active Seismic Sources

Interest in measuring displacement gradients, such as rotation and strain, is growing in many areas of geophysical research. This results in an urgent demand for reliable and field-deployable instruments measuring these quantities. In order to further establish a high-quality standard for rotation and strain measurements in seismology, we organized a comparative sensor test experiment that took place in November 2019 at the Geophysical Observatory of the Ludwig-Maximilians University Munich in Fürstenfeldbruck, Germany. More than 24 different sensors, including three-component and single-component broadband rotational seismometers, six-component strong-motion sensors and Rotaphone systems, as well as the large ring laser gyroscopes ROMY and a Distributed Acoustic Sensing system, were involved in addition to 14 classical broadband seismometers and a 160 channel, 4.5 Hz geophone chain. The experiment consisted of two parts: during the first part, the sensors were co-located in a huddle test recording self-noise and signals from small, nearby explosions. In a second part, the sensors were distributed into the field in various array configurations recording seismic signals that were generated by small amounts of explosive and a Vibroseis truck. This paper presents details on the experimental setup and a first sensor performance comparison focusing on sensor self-noise, signal-to-noise ratios, and waveform similarities for the rotation rate sensors. Most of the sensors show a high level of coherency and waveform similarity within a narrow frequency range between 10 Hz and 20 Hz for recordings from a nearby explosion signal. Sensor as well as experiment design are critically accessed revealing the great need for reliable reference sensors.ISSN:1424-822