Axial force prediction based on signals of the elastic wave propagation and artificial neural networks

The identification of internal forces is not only important to preserve the structure integrity but also to understand how their certain elements and connections work. Two examples of laboratory test are discussed in this paper. The first is related to an aluminium rod mounted in a stand where compression load was applied. Due to the relaxation phenomenon force prediction becomes even more important in case of compressed bolts. Thus, the second example is related to a bolted flange connection during static tensile test. Four out of six bolts were equipped with washer load cells. Alternatively, selected bolts were equipped with piezoelectric transducers (actuator and sensor) in order to measure signals of elastic waves. It was noted that the load increasing causes changes in the measured signals. Principal components analysis was used for dimensionality reduction of measured signals. The aim of this study is to investigate the use of elastic waves and artificial neural networks for the purpose of the force of identification. Examples of preliminary results have shown that axial forces may be estimated with relatively good accuracy

Prognozowanie rozwoju technologii drogowych na podstawie metody delfickiej – wybrane zagadnienia

An objective of this research project is an analysis of development directions of new materials, technologies and pavement structures used in road industry, taking into account special environmental conditions and sustainable development rules. Results of the first round of conducted study based on the foresight method are described in this paper. Such results are helpful to provide support for making a long term strategy decisions by the government. Selected results and analysis in the scope of identification of the main research areas and hypothesis connected with developments of road technology are shown in this paper with a special focus on the construction of the durable pavements. It was found that the most important task is related to developments of the asphalt and cement pavements technology providing at least 30 years durability period. The construction of such pavements is possible only when high quality of work is provided and there is further road technology development as a result of the science and industry cooperation.  Celem realizowanego projektu badawczego jest analiza kierunków rozwoju nowych materiałów, technologii i konstrukcji nawierzchni stosowanych w budownictwie drogowym z uwzględnieniem szczególnych uwarunkowań środowiskowych i zasad zrównoważonego rozwoju. W artykule przedstawiono wyniki pierwszej rundy badania eksperckiego w którym wykorzystano metodę foresightu. Badania studialne przydatne są w informowaniu decydentów politycznych oraz środowisk opiniotwórczych o pożądanych kierunkach długoterminowego rozwoju i zmian. W niniejszym artykule przedstawiono wybrane wyniki badań i analiz w zakresie identyfikacji głównych obszarów i tez badawczych związanych z prognozowanymi kierunkami rozwoju budownictwa drogowego. Omówiono zidentyfikowany obszar badawczy dotyczący technologii budowy trwałych nawierzchni drogowych w Polsce. Wykazano, że najważniejszym obecnie zadaniem w zakresie budowy nawierzchni drogowych jest prowadzenie prac nad rozwojem technologii asfaltowych i z betonu cementowego, które zapewnią co najmniej 30-letnią trwałość nowo budowanym nawierzchniom. Stwierdzono, że budowa trwałych nawierzchni drogowych jest możliwa tylko w przypadku zapewnienia wysokiej jakości wykonawstwa robót oraz rozwoju badań w ramach współpracy jednostek naukowych z szeroko pojętą gospodarką

DIG-MAN: Integration of digital tools into product development and manufacturing education

General objectives of PRODEM education. Teaching of product development requires various digital tools. Nowadays, the digital tools usually use computers, which have become a standard element of manufacturing and teaching environments. In this context, an integration of computer-based technologies in manufacturing environments plays the crucial and main role, allowing to enrich, accelerate and integrate different production phases such as product development, design, manufacturing and inspection. Moreover, the digital tools play important role in management of production. According to Wdowik and Ratnayake (2019 paper: Open Access Digital Tool’s Application Potential in Technological Process Planning: SMMEs Perspective, https://doi.org/10.1007/978-3-030-29996-5_36), the digital tools can be divided into several main groups such as: machine tools and technological equipment (MTE), devices (D), internet(intranet)-based tools (I), software (S). The groups are presented in Fig. 1.1. Machine tools and technological equipment group contains all existing machines and devices which are commonly used in manufacturing and inspection phase. The group is used in physical shaping of manufactured products, measurement tasks regarding tools and products, etc. The next group of devices (D) is proposed to separate the newest trends of using mobile and computer-based technologies such as smartphones or tablets and indicate the necessity of increased mobility within production sites. The similar need of separation is in the case of internet(intranet)-based tools which indicate the growing interest in network-based solutions. Hence, D and I groups are proposed in order to underline the significance of mobility and networking. These two groups of the digital tools should also be supported in the nearest future by the use of 5G networks. The last group of software (S) concerns computer software produced for the aims of manufacturing environments. There is also a possibility to assign the defined solutions (e.g. computer programs) to more than one group (e.g. program can be assigned to software and internet-based tools). The main role of tools allocated inside separate groups is to support employees, managers and customers of manufacturing firms focused on abovementioned production phases. The digital tools are being developed in order to increase efficiency of production, quality of manufactured products and accelerate innovation process as well as comfort of work. Nowadays, digital also means mobile. Universities (especially technical), which are focused on higher education and research, have been continuously developing their teaching programmes since the beginning of industry 3.0 era. They need to prepare their alumni for changing environments of manufacturing enterprises and new challenges such as Industry 4.0 era, digitalization, networking, remote work, etc. Most of the teaching environments nowadays, especially those in manufacturing engineering area, are equipped with many digital tools and meet various challenges regarding an adaptation, a maintenance and a final usage of the digital tools. The application of these tools in teaching needs a space, staff and supporting infrastructures. Universities adapt their equipment and infrastructures to local or national needs of enterprises and the teaching content is usually focused on currently used technologies. Furthermore, research activities support teaching process by newly developed innovations. Figure 1.2 presents how different digital tools are used in teaching environments. Teaching environments are divided into four groups: lecture rooms, computer laboratories, manufacturing laboratories and industrial environments. The three groups are characteristic in the case of universities’ infrastructure whilst the fourth one is used for the aims of internships of students or researchers. Nowadays lecture rooms are mainly used for lectures and presentations which require the direct communication and interaction between teachers and students. However, such teaching method could also be replaced by the use of remote teaching (e.g. by the use of e-learning platforms or internet communicators). Unfortunately, remote teaching leads to limited interaction between people. Nonverbal communication is hence limited. Computer laboratories (CLs) usually gather students who solve different problems by the use of software. Most of the CLs enable teachers to display instructions by using projectors. Physical gathering in one room enables verbal and nonverbal communication between teachers and students. Manufacturing laboratories are usually used as the demonstrators of real industrial environments. They are also perfect places for performing of experiments and building the proficiency in using of infrastructure. The role of manufacturing labs can be divided as: • places which demonstrate the real industrial environments, • research sites where new ideas can be developed, improved and tested. Industrial environment has a crucial role in teaching. It enables an enriched student experience by providing real industrial challenges and problems

Anomaly detection in the concrete arc girder subjected to fatigue test

A steel reinforced concrete arch of a bridge girder has been subjected to static and fatigue tests. The aim of this study is the application of guided waves in non-destructive diagnostics of civil engineering structures and early damage detection. Two piezoelectric transducers were mounted at a distance of 1 m to monitor area of the arch keystone. After every 500 000 cycles the signals of elastic waves have been measured and the girder visual examination was carried out. It turned out that both the load magnitude and the appearance of cracks have affected the signal changes. The obtained signal database has been used to train artificial neural networks and establish a diagnostic system. The results of the conducted tests have showed good sensitivity of anomaly detection and satisfying accuracy of load identification

Application of Elastic Waves and Neural Networks for the Prediction of Forces in Bolts of Flange Connections Subjected to Static Tension Tests

There is a group of measurement techniques that can be used in the task of force identification in steel bolts. In this paper, the potential of elastic wave propagation signals was studied for possible application in force monitoring systems. A series of laboratory tests was carried out on flange connections subjected to static tensile tests. Each one contained six screws of the same diameter. Four bolts were equipped with washer load cells. Alternatively, selected bolts were equipped with piezoelectric transducers (actuator and sensor) in order to measure the elastic wave signals. Principal components analysis, time of arrival, and neural network compression were used for dimensionality reduction of the measured signals. Examples of the obtained results with respect to the studied connections show that the tension forces in bolts can be estimated with relatively good accuracy

Challenges in assessing the vibrations influence on people in buildings using non-contact measurements

This research article presents a comparative analysis of vibration assessments in lecture halls to investigate their influence on people using contact (accelerometers) and non-contact (laser vibrometers) measurement techniques. The study aims to verify the accuracy and reliability of vibration analysis in relation to two approaches and determined physical parameters, i.e. acceleration amplitudes and vibration velocities. The intriguing fact was that none of the building users reported any perceived discomfort from vibrations, despite the determined parameters of the signal measured using a laser vibrometer indicating exceedance of permissible vibration amplitudes in several frequency bands. The conducted comparative analysis leads to the conclusion that the location of the laser head tripod on the vibrating floor introduces significant vibration amplification, which in turn may lead to an incorrect assessment of the impact of vibrations on people in buildings. The studies described in the article were carried out in accordance with the procedure contained in the Polish national standard PN-B-02171. The obtained results and the resulting conclusions are an important contribution to a better understanding of the advantages and limitations resulting from the use of non-contact measurements

Digitalizacja obiektów zabytkowych z wykorzystaniem nowoczesnych technologii i narzędzi

The aim of the paper is to present some experiences of using modern technologies to historical buildings digitalization. The emphasis is placed on the possibilities of spatial data collecting, as well as on subsequent 3D modelling. The paper describes the proposed survey techniques which are based on the Terrestrial Laser Scanning and photogrammetry. The authors obtained the point cloud by using the laser scanner Faro Focus 3D and dedicated software to combine scans (target based and cloud to cloud methods). The paper also provides an introduction to issues related to a method of building structure modelling based on a pointcloud. The authors proposed some computer software tools that could improve work with a point cloud and the modelling process. The resulting 3D model could be both a source of information about historical building and a sufficient base to create computational model with spatial finite elements. The subject of the case study is the St. Hubert Chapel located in Rzeszów (Poland) and built in the middle of the 18th century under the patronage of the Lubomirski family. This rococo chapel is one of the most valuable architectural monuments in the region. Historical Building Information Model (HBIM) could be helpful in analysis, visualisations and conservation practice of this precious monument. Diagnosing the current object state and assessing its technical condition could be the purpose of creating a computational FEM model.Celem artykułu jest przedstawienie doświadczeń związanych z wykorzystaniem nowoczesnych technologii do digitalizacji obiektów zabytkowych. Zwrócono uwagę na możliwości pozyskiwania danych przestrzennych, a także na późniejsze modelowanie 3D. W artykule opisano proponowane techniki pomiarowe oparte na naziemnym skaningu laserowym i fotogrametrii. Autorzy uzyskali chmurę punktów wykorzystując skaner laserowy Faro Focus 3D oraz dedykowane oprogramowanie do łączenia skanów (metodą opartą na punktach referencyjnych oraz dopasowaniu chmura do chmury). Artykuł stanowi również wprowadzenie do zagadnień związanych z modelowaniem konstrukcji budynku w oparciu o chmurę punktów. Autorzy zaproponowali kilka narzędzi w postaci oprogramowania komputerowego, które mogłyby usprawnić pracę z chmurą punktów i proces modelowania. Powstały model 3D może być zarówno źródłem informacji o zabytkowym budynku, jak i wystarczającą bazą do stworzenia modelu obliczeniowego z elementami skończonymi. Przedmiotem badań jest kaplica św. Huberta zlokalizowana w Rzeszowie (Polska), zbudowana w połowie XVIII wieku pod patronatem rodu Lubomirskich. Kaplica w stylu rokoko jest jednym z cenniejszych zabytków architektury w regionie. Historical Building Information Model (HBIM) może być pomocny w analizie, wizualizacji i praktyce konserwatorskiej tego cennego zabytku. Celem stworzenia modelu obliczeniowego MES może być zdiagnozowanie aktualnego stanu obiektu i ocena jego stanu technicznego

Future Trends in Road Pavement Technologies Development in the Context of Environmental Protection

Construction of modern and durable asphalt and cement pavements requires high quality materials and suitable technologies that take into account sustainability concerns which are related to the environmental protection, mitigation and compensation for road construction effects on surface water and groundwater, soil, air, wildlife, landscape, vibration and noise. The objectives of this paper are to identify possible development directions of materials and technologies in road construction in the time perspective of approximately 30 years. In order to achieve that goal a nationwide Delphi survey with 150 invited experts was deployed. The study concluded that binding materials with improved viscoelastic range – and often with specific modifications – would continue to play a leading role. Furthermore, technologies that enable monitoring the state of road pavement condition in a continuous manner would be used to a greater range. Introduction of sensors into the pavement network would lead to the construction of “smart” roads while spreading of nanomaterial technology would improve the durability and reliability of road pavement construction