Ocjena postojećeg stanja zidane građevine primjenjom dinamičkih mjerenja

master's thesis

• Title (english): Assessment of existing masonry building by using dynamic measurements
• Author: Marta Ivančić
• Mentor: Ivan Duvnjak (mentor)
• Committee member: Marko Bartolac (predsjednik povjerenstva)
• Committee member: Ivan Duvnjak (član povjerenstva)
• Committee member: Ana Skender (član povjerenstva)
• Granter: University of Zagreb; Faculty of Civil Engineering; (Engineering Mechanics); Zagreb
• Defense date and country: 2022-09-29, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Civil Engineering

Abstract

Tema ovog diplomskog rada je ocjena postojećeg stanja zidane građevine primjenom dinamičkog mjerenja. Točnije, radi se o zgradi u centru Zagreba na adresi Vjenceslava Novaka 7 koja je nastradala u potresu. Predmetni projekt preuzet je iz arhive poduzeća „SLF projekt d.o.o.“ koja se bavi projektiranjem, nadzorom i vještaćenjem. Uz njihov pristanak i dogovor postojeća građevina je izmjerena te je napravljen numerički model u računalnom programu „SCIA Engineer 21.1.“ U svrhu izrade elaborata ocjene postojećeg stanja zidane konstrukcije inženjeri u spomenutom poduzeću odradili su detaljan pregled konstrukcije te su proveli neke od istražnih radova iste. Također, izrađen je numerički model u računalnom programu „3Muri“. Sva dokumentacija vezana za projekt je ustupljena i korištena za usporedbnu dobivenih rezultata. Na samom početku rada opisane su neke od metoda ispitivanja zidanih građevina te konstruktivni elementi predmetne građevine sa pripadajućim dimenzijama. Središnji dio rada obuhvaća detaljniji opis provedenog dinamičkog mjerenja te je provedena ocjena rezultata prema kriteriju ortogonalnosti (MAC faktor). Također je provedena kontrola osnovnih zahtjeva za nosive zidove prema normi HRN EN 1998-1:2011/NA:2011/A1. Nadalje, dani su osnovni dinamički parametri konstrukcije dobiveni ispitivanjem te pripadni modalni oblici.Kako bi se odredilo što točnije stanje konstrukcije izrađen je numerički model koji je baždaren na temelju dinamičkih parametara dobivenih eksperimentalnim ispitivanjem. Zbog nepoznatih parametara, mehaničkih karakteristika materijala i nepoznatih rubnih uvjeta izrađeno je više modela sa različitim varijacijama. Prvotno je izrađen inicijalni model na kojem je provedeno poboljšanje modela varijacijom modula elastičnosti opeke, uklanjanjem vitkih elemenata koji nemaju značajan utjecaj na krutost te zamjenom pregradnih zidova pripadnim linijski opterećenjem. Na jednom od spomenutih modela unešene su značajne pukotine na konstrukciji unutar granica koje pokrivaju frekvencije dobivene eksperimentalnim ispitivanjem. Provedena je i usporedba sa rezultatima koje su dobili inženjeri u SLF projektu. U posljednjem poglavlju površinski je zagrebana tema sanacije konstrukcije. Prikazana je analiza dinamičkih parametara prije i poslije sanacije, odnosno provjera povećanja krutosti konstrukcije sa navadenim ojačanjima. Zaključno je dano mišljenje o postojećem stanju konstrukcije na temelju izmjerenih rezultata u kombinaciji sa provedenom numeričkom analizom.

Abstract (english)

The topis of this thesis is the assesment of the existing state of the masonry building using dynamic measurement. Precisely, it is a building in the center of Zagreb at the adress Vjenceslava Novaka 7 that was damaged in the earthquake.
The project was taken over from the archive of company „SLF projekt d.o.o.“ which deals with designing, supervision and expertise. With their consent and agreement, the existing building was measured and the numerical model was created in the „SCIA Engineer 21.1.“ softver. In the purpose of creating an evaluation report of the existing condition of the masonry structure, the engineers in the mentioned company performed a detailed inspection of the stucture and carried out some of investigative work. Also, a numerical model was created in softver „3Muri“. All documentation related to the project was intoduces and used to compare the obrained results. At the beggining of the thesis are described some of the methods of testing masonry buildings and the structural elements of the building with associated dimensions. The central part of the paper inludes a more detailed description of the performed dynamic measurement, and an evaluation of the results according to the criterion of orthogonality (MAC factor). The basic requirements for load bearing walls were also checked according to the HRN EN 1998-1:2011/NA:2011/A1 standard. Furthermore, the basic dynamic parameters of the structure obtained by testing and the corresponding modal shapes are given. In order to determine as accurately as possible the condition of structure, a numerical model was created that was adjusted based on the dynamic parameteres obtained by experimental testing. Due to unknown parameters, mechanical characteristics of the material and unknown boundry conditions, several model with different wariations were made. An initial model was create on which the improvement of the model was carried out by changing the modulus of elasticity of the brick and replacing the partition walls with the corresponding line load. On one of the mentioned models, significant cracks were inroduced in the construction within the limits that cover the frequencies obtained by experimental testing. A comaprison was also made with the results obtained by the engineers in the SLF project. In the last chapter the topic of contrustion rehabilitation is initiated. An analysis of the dynamic parameters before and after the rehabilitation is presented that is the verification of the increased stiffness of the structure with addes reiforcements. In conclusion is given an opinion on the existing state of the structure based on the measured result in combination with the performed numerical analysis.

• Keywords: potres; dinamički parametri; zidana konstrukcija; ispitivanje; numerička analiza
• Keywords (english): earthquake; dynamic parameters; masontry construction; testing; numerical analysis
• Language: croatian
• URN:NBN: urn:nbn:hr:237:669719
• 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: 2023-02-01 08:08:44