Primjena brzine ultrazvuka za ocjenu mehaničkih svojstava betona nakon djelovanja visokih temperatura

undergraduate thesis

• Title (english): Application of ultrasound pulse velocity to assess the mechanical properties of concrete exposed to elevated temperatures
• Author: Marko Mačukat
• Mentor: Marija Jelčić Rukavina (mentor)
• Committee member: Marina Bagarić (predsjednik povjerenstva)
• Committee member: Ana Baričević (član povjerenstva)
• Committee member: Bojan Milovanović (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Materials); Zagreb
• Defense date and country: 2021-09-21, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering

Abstract

Djelovanje požara uzrokuje smanjenje mehaničkih svojstava betona u armirano- betonskim konstrukcijama. Iz te činjenice proizlazi potreba za kontrolom kvalitete betonskih konstrukcija nakon izloženosti požaru kako bi se mogla procijeniti preostala nosivost i mogućnost sanacije požarom oštećene konstrukcije. Prilikom provođenja razornih metoda ispitivanja, betonski uzorci uzimaju se direktno iz oštećene konstrukcije što za posljedicu ima dodatno oslabljenje same konstrukcije. Iz tog razloga, nerazorne metode ispitivanja predstavljaju dobar alat za ocjenu preostale nosivosti konstrukcija. U ovom radu je opisano mjerenje brzine prolaska ultrazvuka koja predstavlja najčešće korištenu nerazornu metodu ispitivanja. U radu je nadalje analiziran odnos između preostalih mehaničkih svojstava (tlačne čvrstoće i modula elastičnosti) te brzine ultrazvuka za betone normalnih i visokih čvrstoća izloženih temperaturama do 600 ° C.

Abstract (english)

Exposure to fire causes deterioration of the mechanical properties of concrete in reinforced concrete structures. This results in the need to control the quality of concrete structures after exposure to fire in order to assess the remaining load-bearing capacity and the possibility of repairing a fire-damaged structure. When performing destructive testing procedures, concrete specimens are taken directly from the damaged structure, resulting in additional weakening of the structure itself. For this reason, non-destructive testing methods are a good tool for estimating the remaining load bearing capacity of structures. In this paper, the measurement of ultrasonic pulse velocity (UPV) is described, which is the most commonly used non destructive testing method for reinforced concrete elements. Furthermore, the relationship between the residual mechanical properties (compressive strength and modulus of elasticity) and the UPV is analyzed for normal and high strength concretes exposed to temperatures up to 600 ° C.

• Keywords: Betoni visokih čvrstoća; brzina ultrazvuka; visoke temperature; mehanička svojstva
• Keywords (english): High strength concrete; ultrasound pulse velocity; high temperatures; mechanical properties
• Language: croatian
• URN:NBN: urn:nbn:hr:237:319681
• 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: 2022-04-12 08:10:57