Primjena numeričkog modela za predviđanje uporabnog vijeka na Vijaduktu Zalesina

master's thesis

• Title (english): Application of numerical model for service life prediction on the Zalesina Viaduct
• Author: Stjepan Šimunović
• Mentor: Marija Kušter Marić (mentor)
• Committee member: Ivan Ćurković (predsjednik povjerenstva)
• Committee member: Marija Kušter Marić (član povjerenstva)
• Committee member: Ivan Lukačević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Structures); Zagreb
• Defense date and country: 2021-09-23, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering; Supporting Structures

Abstract

Vijadukt Zalesina se nalazi na snježnoj dionici Ravna Gora-Delnice, autoceste Rijeka-Zagreb (A6). Tijekom zime po građevini se posipaju velike količine soli što je jedan od glavnih razloga oštećenja vijadukta. Sol, smrzavanje i otapanje leda, ulazak klorida u betonske strukture i karbonatizacija glavni su uzroci oštećenja armiranobetonskih mostova. U diplomskom radu se analiziraju mehanizmi degradacije, daje pregled tehnika istraživanja i procjenjuje uporabni vijek vijadukta Zalesina pomoću računalnog programa Life-365. Tradicionalni način projektiranja mostova u velikoj se mjeri temelji na iskustvu projektanta. U praksi, projektanti koriste gotove (unaprijed pripremljene) vrijednosti iz tablica bez potrebe za dubinskom analizom i izučavanjem njihova značenja. Osnovne veličine koje se uzimaju u obzir kod projektiranja jesu minimalna debljina zaštitnog sloja betona i maksimalna širina pukotina. Sukladno Europskim normama, recentno projektiranje osim navedenih veličina, uzima još i maksimalni vodo-cementni faktor, minimalnu količinu cementa i minimalni sadržaj zraka. Ako su poznate karakteristike ugrađenog materijala i interakcija s okolinom, može se odrediti dotrajavanje i procijeniti uporabni vijek postojećih mostova, korištenjem numeričkih modela. S ovakvim pristupom konstrukcija će imati prihvatljivo dug uporabni vijek. Model Life-365 je razvijen ne samo za procjenu uporabnog vijeka konstrukcije nego i za određivanje troškova održavanja betonskih konstrukcija izloženih kloridima.

Abstract (english)

The Zalesina viaduct is located on the snowy Ravna Gora – Delnice section of the A6 Rijeka- Zagreb motorway. During the winter, the structure is treated by a large amount of road salt, which is one of the main reasons for damage on the viaduct. Salt treatment, water freezing and ice melting, chloride invasion and carbonation are the main causes for damage in reinforced concrete bridges. This graduate thesis analyses degradation mechanisms, provides an overview of testing techniques, and estimates service life of the Zalesina viaduct using the Life-365 software. The traditional methods of bridge design are mostly based on designer experience. In practice, designers use standard (by experience) table values without the need for in-depth analysis and value interpretation. The basic quantities considered in design are the minimum thickness of the concrete protective layer and maximum crack width. In accordance with the European standards, besides the stated quantities, recent designs consider maximum water-cement factor, minimum amount of cement and minimum air content as well. If the specifications of the embedded material and the environmental impact are known, deterioration and service life of the existing bridges can be determined by using numerical models. This approach leads to acceptable service life. In addition to estimate structure service time, the Life-365 model is developed to estimate maintenance costs for concrete structures exposed to chlorides.

• Keywords: kloridi; Life-365; mehanizmi degradacije; uporabni vijek; vijadukt Zalesina
• Keywords (english): chlorides; degradation mechanisms; Life-365; service life; Zalesina viaduct
• Language: croatian
• URN:NBN: urn:nbn:hr:237:323834
• 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: Construction Management; 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: 2021-11-22 08:56:51