Mehanizmi loma betona

master's thesis

• Title (english): Concrete Fracture Mechanisms
• Author: Tomislav Rešetar
• Mentor: Marko Bartolac (mentor)
• Committee member: Marta Šavor Novak (predsjednik povjerenstva)
• Committee member: Mario Uroš (član povjerenstva)
• Committee member: Marko Bartolac (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Engineering Mechanics); Zagreb
• Defense date and country: 2024-02-15, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering

Abstract

Mehanika loma je tehnička i znanstvena disciplina koja proučava nastanak i propagaciju pukotina u materijalima. Zbog pojave pukotina, odnosno defekata, stvarna čvrstoća materijala može biti nekoliko puta manja od teorijske čvrstoće dobivene po principima klasične mehanike. Cilj mehanike loma je razumijevanje polja naprezanja i deformacija oko vrha pukotine te definiranje uvjeta koji utječu na njeno daljnje širenje. Beton je heterogeni kompozitni materijal koji je zbog svog sastava pun različitih defekata. Iako se pri projektiranju beton smatra krhkim materijalom zanemarive vlačne čvrstoće, u stvarnosti se ponaša kvazi-krhko. Pri vlačnom naprezanju na otvaranje pukotina troši se energija, što betonu daje određenu žilavost koja se često ne uzima u obzir u klasičnoj teoriji čvrstoće betona. Mehanika loma betona proučava pojavu i širenje pukotina u betonu te definira modele kojima bi se što preciznije prikazalo ponašanje betonskih elemenata i konstrukcija. U radu su opisani parametri mehanike loma i pojave koje se događaju prilikom loma betona. Nadalje, obrađeni su modeli kojima se opisuje ponašanje betona pri vlačnom naprezanju i eksperimentalne metode kojima se dobivaju parametri loma betona. Za kraj riješeno je nekoliko praktičnih primjera.

Abstract (english)

Fracture mechanics is a technical and scientific discipline that studies the initiation and propagation of cracks in materials. Due to the occurrence of cracks, or defects, the actual strength of materials can be several times lower than the theoretical strength obtained according to the principles of classical mechanics. The goal of fracture mechanics is to understand the stress and deformation fields around the crack tip and to define conditions that influence its further propagation. Concrete is a heterogeneous composite material filled with different defects due to its composition. Although concrete is considered to be a brittle material with negligible tensile strength, it behaves quasi-brittle in reality. During tensile stress, energy is consumed on openings of cracks, giving concrete a certain toughness often not considered in classical concrete strength theory. Concrete fracture mechanics study the occurrence and propagation of cracks in concrete, defining models to more precisely depict the behavior of concrete elements and structures. The paper describes fracture mechanics parameters and phenomena that occur during concrete fracture. Furthermore, models describing concrete behavior under tensile stress and experimental methods for obtaining concrete fracture parameters are discussed. Finally, several practical examples are solved.

• Keywords: Mehanika loma; beton; pukotina; zona procesa loma; energija loma
• Keywords (english): Fracture Mechanics; Concrete; Crack; Fracture Process Zone; Fracture Energy
• Language: croatian
• URN:NBN: urn:nbn:hr:237:715098
• Study programme: Title: Civil Engineering; specializations in: Construction Management, Transportation Engineering, Geotechnical Engineering, Hydraulic Engineering, Structural Engineering, Construction Materials, Theory and Modeling of Structures; Course: Structural Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka građevinarstva (magistar/magistra inženjer/inženjerka građevinarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2024-03-15 09:35:43