Numerical Study on the Behaviour of Built-up Cold-Formed Steel Corrugated Web Beams End Connections

Corrugated web beams made of cold-formed steel components represent an economical solution for structures, offering high flexural capacity and deformation rigidity. For conventional corrugated web beams, made of thick plates for the flanges and thin sinusoidal steel sheets for the web, the elements can be joined by standard bolted end-plate connections. In the case of corrugated web beams made of thin-walled cold-formed steel components only, additional plates are required to accommodate the shape and position of the profiles. A large experimental program was carried out on corrugated web beams made of cold-formed steel elements. One of the objectives was to determine the capacity of these beams and the influence of several parameters on the response of the beam, but also very important were the end connections of these beams. The recordings obtained from the tests were used to validate a numerical model. Based on the validation of the numerical model, finite element analyses were performed to study four solutions for end connections to facilitate assembly, optimise the number of bolts, and increase the capacity and rigidity. Although the connection can be improved for assembling reasons with the presented solutions, the overall capacity is limited by the components subjected to compression that lose their stability. Doi: 10.28991/CEJ-2023-09-04-01 Full Text: PD

Experimental investigations on built-up cold-formed steel beams connected by resistance spot welding

[EN] The WELLFORMED research project, ongoing at the CEMSIG Research Center of the Politehnica University of Timisoara, proposes to study a new technological solution for built-up beams made of corrugated steel sheets for the web and thin-walled cold-formed steel profiles for the flanges, connected by resistance spot welding. Within the research project, the experimental work includes tensile-shear tests on the lap joint spot-welded specimens, were different combinations of steel sheets with various thicknesses were tested and, tests on full scale beams in bending. The study intends to demonstrate the feasibility of the proposed solutions, to assess their performance and to enlarge the knowledge by using numerical simulations for the optimization of the current solution and to define the limits of the solution’s applicability.This work was supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI - UEFISCDI, project number PN-III-P2-2.1-PED2016-1684 / WELLFORMED - Fast welding cold-formed steel beams of corrugated sheet web, within PNCDI III.Ungureanu, V.; Both, I.; Burca, M.; Grosan, M.; Neagu, C.; Dubina, D. (2018). Experimental investigations on built-up cold-formed steel beams connected by resistance spot welding. En Proceedings of the 12th International Conference on Advances in Steel-Concrete Composite Structures. ASCCS 2018. Editorial Universitat Politècnica de València. 205-212. https://doi.org/10.4995/ASCCS2018.2018.716920521

Total hip arthroplasty in trochanteric fractures

Universitatea de Stat de Medicină şi Farmacie „Nicolae Testemiţanu”, Chişinău, Republica MoldovaIntroducere. Fracturile trohanteriene reprezintă o problemă actuală prin incidența crescută: (75% reprezentând pacienții în vârstă de peste 75 de ani), fiind cauzate preponderent de osteoporoză. Acest tip de fractură, devine adesea o mare problemă deoarece este asociată cu un ansamblu de patologii concomitente, care pot fi acutizate de acest traumatism, fapt care poate cauza deces, sau apariția multor complicații legate de regimul îndelungat la pat și apariția complicațiilor hipodinamice si tromboembolice. Metodele de osteosinteza a acestor fracturi sunt dificile, impun excluderea efortului pe membru până la consolidarea fracturii, deseori complicate cu degradarea implantului sau osteosintezei. Scopul lucrării. Evaluarea rezultatelor tratamentului bolnavilor cu fracturi de masiv trohanterian tratați prin artroplastie de șold în perioada 2018-2022 în secția I a Spitalului Clinic de Traumatologie și Ortopedie. Material și metode. În studiu au fost incluși 44 de pacienți cu fracturi ale sectorului trohanterian, tratați în perioada 2018-2022 în secția I a Spitalului Clinic de Traumatologie și Ortopedie prin artroplastie de șold. Vârsta medie al bolnavilor a constituit 74 ani, predominant fiind tipul de fractură Evans IV/V. Rezultate. Pentru acești 44 de pacienți înrolați în studiu, au fost utilizate proteze totale cimentate (n = 8), bipolare cimentate (n = 25), necimentate (n = 8), cervicocefalică MOORE cimentată (n = 3). Durata medie a internării a fost de 9 zile, în comparație cu cei tratați prin osteosinteză fiind mai mică cu 3-4 zile. În a doua zi după intervenție toți pacienții s-au deplasat cu sprijin pe piciorul afectat. Concluzii. Artroplastia de sold este o variantă optima de tratament chirurgical al pacienților vârstnici cu fracturi trohanteriene cominutive instabile, care asigură o mobilizarea funcțională precoce a bolnavului cu efort deplin pe membru și prevenirea complicațiilor.Introduction. Trochanteric fractures represent a current issue due to high incidence (75% of cases are represented by patients aged over 75 years old), being mainly caused by osteoporosis. This type of fractures often develop into a difficult clinical management situation, because of the association with a set of concomitant pathologies, which can be worsen by this trauma, further, leading even to death or worsening of the patient’s general condition due to long recovery process and hypodynamic and thromboembolic complications. The methods of osteosynthesis of these fractures are difficult, they require the exclusion of effort per member until the fracture is resolved, often complicated by implant degradation or osteosynthesis. The purpose of the thesis. Evaluation of treatment results of patients with massive trochanteric fractures treated by hip total arthroplasty during 2018-2022 in Traumatology and Orthopedic Hospital, section I. Methods and materials. The study included 44 patients with trochanteric fractures treated in the period 2018-2022 in section I of the Clinical Hospital of Traumatology and Orthopedics by hip arthroplasty. The average age of the patients was 74 years, the prevailing type of fracture being Evans IV/V. Results. For these 44 patients enrolled in the study, were used fully cemented prostheses (n = 8), bipolar cemented prostheses (n = 25), uncemented (n = 8), uncemented MOORE prostheses (n = 3). The average duration of hospitalization was 9 days, compared to those treated with osteosynthesis being less than 3-4 days. The day after the intervention, all patients were able to step on the affected leg. Conclusion. Hip arthroplasty is considered an optimal alternative for surgical treatment of elderly patients with unstable communitive trochanteric fractures, which ensures an early functional mobilization of the affected limb and avoiding further complications linked to long term recovery