Comparison of Internal Forces Redistribution and Displacements Subjected to the Dynamic Wind Gusts depending of Point Fixed Glass Connector Model Shape

This paper presents an analysis of the redistribution of stresses and displacements in numerical models of various shapes of glass connectors. Two states of dynamic wind gusts were analyzed: the maximum value of suction and the maximum value of wind pressure. For the sake of simplicity, wind gusts were assumed periodically as a sinusoidal function. The model adopts a rectangular glass plate that transmits wind pressure and suction through the point fixed glass connectors. Therefore, single-arm cross connectors were not only subjected to bending stress, but also to torsion. Four different shapes of connectors were analyzed. In the first part of the numerical analysis, T-shaped and C-shaped cross-sections were adopted, and in the next part, both connectors were modified by adding fillet welds to the models. The dynamic numerical analysis was performed using the finite element method in the ADINA program

Mechanical thrombectomy in acute stroke – Five years of experience in Poland

Objectives Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland. Methods and results We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures. Results Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250±99min. 90.3% of the studied patients had MT within 6h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% – emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b–TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization – in 30.7%, mRS of 0–2 – in 31.4% and mRS of 6 in 22% of cases. Conclusion Our results can help harmonize standards for MT in Poland according to international guidelines

Szkieletowa konstrukcja cięgnowa jako ustrój domu jednorodzinnego

In designing building structures, the most important stage is the selection of appropriate construction solutions, depending on the architectural design, purpose of the facility and the conditions in which the designed facility will be located. When choosing the type of materials from which single-family houses are erected, traditional solutions, such as concrete and brick building elements, are most often chosen. Traditional construction solutions for houses, however, do not always allow for the construction of buildings with sophisticated architecture or in particularly demanding places, e.g. in a seismic zone or in a mining area. In this case, skeletal steel structures can help, because when properly designed they are able to ensure safe operation in these areas. This paper presents an analysis of the use of a skeleton steel tensile structure in a single-family house design.W projektowaniu obiektów budowlanych najważniejszym etapem jest dobór odpowiednich rozwiązań konstrukcyjnych w zależności od projektu architektonicznego, przeznaczenia obiektu oraz warunków, w jakich będzie się znajdował projektowany obiekt. W przypadku doboru rodzaju materiałów, z jakich są wznoszone domy jednorodzinne, najczęściej wybierane są tradycyjne rozwiązania, takich jak betonowe i murowane elementy budynku. Tradycyjne rozwiązania konstrukcyjne domów jednak nie zawsze umożliwiają wykona nie obiektów o wyrafinowanej architekturze lub w miejscach szczególnie wymagających, np. na terenie znajdującym się w strefie sejsmicznym lub w obszarze górniczym. W takim przypadku z pomocą przychodzą szkieletowe konstrukcje stalowe, ponieważ, odpowiednio zaprojektowane, są w stanie zapewnić bezpieczną eksploatację na tych terenach. W pracy przedstawiono analizę zastosowania szkieletowej stalowej konstrukcji cięgnowej w projekcie domu jednorodzinnego

Analysis of the skeleton tension structure as the load-bearing structure of a one-nave hall

In designing cubature buildings, an important stage is the selection of an appropriate construction solution, depending on the intended use and location of the designed building. When selecting the load-bearing structures, the designers strive to ensure that the structure weighs as little as possible, while meeting the strength conditions and ensuring the safe operation of the building. The article compares the load-bearing systems of the steel structure of a one-nave hall due to the economy of execution and meeting the ULS and SLS conditions. The analysis was carried out on four types of transverse system, including three frame systems with tendons and for a frame system with a lattice transom of the “N” type. Static calculations as well as dimensioning and optimization of the transverse load-bearing structures were performed in RFEM program, modelling the hall structure in 3D

Strengthening the existing connection of steel beams with a column

The paper presents a solution that includes strengthening the connection of a support column with beams from both sides, placed in a vertical plane together with the pole. All the bar elements connected in the analyzed node were made of hot-rolled steel I-sections. Due to the need to increase the load on the joined beams to the pole, load-bearing capacity of the primary connection is lost, which necessitates the reinforcement of the existing connection. The analysis carried out in this paper shown exceeding the allowable stresses in the column web at the place of joining the beams. The calculations made in this paper showed the possibilities of restoring the safe operation of the connection node in question, by introducing elements increasing its load-bearing capacity. In addition to analytical calculations, numerical analysis was also performed using the ADINA program

Przegląd współczesnych rozwiązań posadowień konstrukcji inżynierskich

The foundations of various types of engineered structures are a key element of any facility as it is the only point of contact with the subsoil and ensures stability and safety during operation. During the design of a structure, a suitable foundation solution should be selected that will ensure adequate stability in encountered ground conditions. This article presents contemporary solutions for the foundations of engineered structures that have been subjected to analysis and research over the last few years.Posadowienie różnego rodzaju konstrukcji inżynierskich jest kluczowym elementem każdego obiektu inżynierskiego, gdyż stanowi jedyne połączenie z podłożem gruntowym oraz zapewnia stabilność i bezpieczeństwo w trakcie eksploatacji budowli. Projektując daną konstrukcję należy dobrać odpowiednie rozwiązanie posadowienia, które zapewni odpowiednią stabilność w napotkanych warunkach gruntowych. W tym artykule przedstawiono najnowsze rozwiązania posadowień konstrukcji inżynierskich, które zostały poddane analizie i badaniom na przestrzeni kilku ostatnich lat

Reduction of mechanical interactions with the use of a rubber composite

The paper presents the results of research on the reduction of mechanical interactions of the composite produced from components resulting from the recycling of used car tires and plastic bottles (i.e. polyethylene terephthalate, colloquially called PET). Composite samples for testing were made with three thicknesses of mixtures rubber granules and PET flakes. The whole was joined together with an epoxy resin and formed into the shape of discs, which were then subjected to mechanical interactions to determine the damping properties depending on the thickness of the considered samples. The samples were subjected to evaluation on the author’s measuring stand. Obtained results of the research indicated that the developed composite well suppresses mechanical interactions resulting from dynamic interactions involving vibrations or vibrations in the analyzed frequency range. The developed composite can be used as a contribution to use in building materials that reduce mechanical interactions

Mechanical thrombectomy in acute stroke : five years of experience in Poland

Objectives: Mechanical thrombectomy (MT) is not reimbursed by the Polish public health system. We present a description of 5 years of experience with MT in acute stroke in Comprehensive Stroke Centers (CSCs) in Poland. Methods and results: We retrospectively analyzed the results of a structured questionnaire from 23 out of 25 identified CSCs and 22 data sets that include 61 clinical, radiological and outcome measures. Results: Most of the CSCs (74%) were founded at University Hospitals and most (65.2%) work round the clock. In 78.3% of them, the working teams are composed of neurologists and neuro-radiologists. All CSCs perform CT and angio-CT before MT. In total 586 patients were subjected to MT and data from 531 of them were analyzed. Mean time laps from stroke onset to groin puncture was 250 99 min. 90.3% of the studied patients had MT within 6 h from stroke onset; 59.3% of them were treated with IV rt-PA prior to MT; 15.1% had IA rt-PA during MT and 4.7% - emergent stenting of a large vessel. M1 of MCA was occluded in 47.8% of cases. The Solitaire device was used in 53% of cases. Successful recanalization (TICI2b–TICI3) was achieved in 64.6% of cases and 53.4% of patients did not experience hemorrhagic transformation. Clinical improvement on discharge was noticed in 53.7% of cases, futile recanalization - in 30.7%, mRS of 0–2 - in 31.4% and mRS of 6 in 22% of cases. Conclusion: Our results can help harmonize standards for MT in Poland according to international guideline