Proračun prema teorijama čvrstoće

undergraduate thesis

• Title (english): Design according to failure criteria
• Author: Karlo Grgurić
• Mentor: Ana Skender (mentor)
• Committee member: Ivan Duvnjak (predsjednik povjerenstva)
• Committee member: Ana Skender (član povjerenstva)
• Committee member: Diana Šimić Penava (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Engineering Mechanics); Zagreb
• Defense date and country: 2021-07-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering

Abstract

U ovom radu opisuje se proračun prema teorijama čvrstoće za jednoosno ili višeosno stanje naprezanja. Problem određivanja kritičnih vrijednosti glavnih naprezanja može se javiti kod višeoosnog stanja naprezanja zbog velikog broja kombinacija i složenosti uređaja za ispitivanje. Zbog toga se uvode teorije čvrstoće, kojima se višeosno stanje naprezanja svodi na jednoosno stanje naprezanja ekvivalentno po opasnosti pojave loma ili plastičnih deformacija. Svaka je teorija objašnjena sa svojim prednostima i manama, te je utvrđeno određeno poklapanje rezultata teorije čvrstoće s eksperimentalnim rezultatima za elastoplastični ili krhki materijal. Nakon objašnjenja svih teorija čvrstoće, napravljena je usporedba između teorija čvrstoće i veza određene teorije čvrstoće s duktilnosti materijala. Ista teorija će za elastoplastične i krhke materijale davati različite rezultate. Na kraju rada se preko numeričkog primjera prikazuje primjena određene teorije čvrstoće u praksi, a za zadano opterećenje određene su dimenzije poprečnih presjeka štapa.

Abstract (english)

In this thesis, the calculation of uniaxial and multiaxial stress-states using strength theories is specified. The problem of determining critical values of principal stress can arise when analysing multiaxial stress-states because of a large number of combinations and the complexity of the testing apparatus. Because of the reasons referred to earlier, strength theories have been introduced. They are used for reducing multiaxial stress-state to uniaxial stress-state, which are equivalent when considering the occurrence of a fracture or plastic deformation. Several theories are explained, along with advantages and disadvantages. Furthermore, certain overlaps of experimental data for elastoplastic or fragile materials and strength theories results have been determined. After each strength theory was explained, a comparison between different strength theories was made and the connection between each one and the ductility of the used material was defined, which means that the same theory will give different results, depending on the type of material. At the end of the thesis, using a numerical example, an application of a specific strength theory in practice was shown by dimensioning several cross-sections.

• Keywords: čvrstoća; dopušteno naprezanje; kritično naprezanje; ekvivalentno naprezanje; koeficijent sigurnosti; kriterij čvrstoće
• Keywords (english): strength; permissible stress; critical stress; equivalent stress; factor of safety; strength criteria
• Language: croatian
• URN:NBN: urn:nbn:hr:237:827963
• Study programme: Title: Civil Engineering; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka građevinarstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka građevinarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2022-04-01 08:02:18