Domagoj Damjanović

POSITIVE INTERACTION OF INDUSTRIAL AND RECYCLED STEEL FIBRES IN FIBRE REINFORCED CONCRETE

AbstractIn line with current ”green” transport initiatives, Croatia plans to build over the next investment period a high speed railway line which will connect central Croatia and its capital with coastal regions of the country. According to design documents, the track system will be built using ballastless concrete solutions. In the scope of the project “Concrete track system – ECOTRACK”, researchers from the University of Zagreb - Faculty of Civil Engineering analysed a new material, i.e. the rubberized hybrid fibre reinforced concrete (RHFRC), in order to find out whether its properties are adequate for the proposed concrete track system. The RHFRC contains by-products from mechanical recycling of waste tyres (rubber and steel fibres). The study of fibre and rubber interaction and their contribution to mechanical properties of the fibre reinforced concrete is presented, as extensive research on positive interaction between industrial and recycled steel fibres has not as yet been made. The results show ...

Punching strength of flat slabs with and without shear reinforcement

Nosivost na posmicni proboj iznimno je važan parametar pri projektiranju ravnih ploca, odnosno ploca oslonjenih neposredno na stupove, bez greda između stupova. Prikazani su proracunski modeli proboja ploca prema Eurokodu 2, ACI Codu 318 i fib Model Codu 2010. Opisana su provedena vlastita eksperimentalna istraživanja proboja ploca s posmicnom armaturom i bez nje te su dobiveni rezultati uspoređeni s predviđanjima spomenutih proracunskih modela. Uoceno je da svi proracunski modeli podcjenjuju eksperimentalno dobivenu nosivost na proboj u slucaju ploca bez posmicne armature. Kod ploca s posmicnom armaturom, uoceno je precjenjivanje nosivosti na proboj prema proracunskom modelu Eurokod 2.

Stress–strain relationships and influence of testing parameters on coupon test results

Tensile steel-coupon testing qualifies as one of the more commonly used experiments for determination of basic parameters for structural design. Such

An innovative methodology of assessing the climate change impact on cultural heritage

ABSTRACT Climate change is expected to have a severe impact on cultural heritage in the future. This study presents the methodology developed during the FP7 project Climate for Culture, of assessing the climate change impact on collection objects in cultural heritage buildings. The main innovation lies in coupling new high resolution future climate projections with building simulation tools in order to predict future indoor climate and identify future risks in historic buildings. The case study is an intermittently heated wooden chapel in Croatia. The whole building simulation model of the chapel was validated using a newly developed method of accuracy assessment in the context of preventive conservation. Even though modeling intermittent heating induces limitations in the model, it can be used for computing of future indoor data. Future indoor climate data was assessed for possible risks of biological, mechanical, and chemical damage to painted wooden panels using the newly developed specific climate risk assessment. When using this method of damage assessment on buildings with active climate control, especially with intermittent heating, it is recommended to determine the relevant season for the damage process in order to objectively analyze results.

Application of recycled steel fibres in concrete elements subjected to fatigue loading

Dodavanjem celicnih vlakana u beton poboljsavaju se njegova svojstva pri zamoru. Opisana su eksperimentalna istraživanja betonskih elemenata s recikliranim celicnim vlaknima pri ciklickom opterecenju. Prikazani su proracunski modeli zamora prema fib Model Code 2010, ACI 215 i JSCE smjernicama. Rezultati proracunskih modela uspoređeni su s rezultatima eksperimentalnog istraživanja. Uoceno je da, u pravilu, svi proracunski modeli podcjenjuju eksperimentalno određenu otpornost betona pri zamoru. Dan je prijedlog korekcije fib Model Code modela.Dodavanjem čeličnih vlakana u beton poboljšavaju se njegova svojstva pri zamoru. Opisana su eksperimentalna istraživanja betonskih elemenata s recikliranim čeličnim vlaknima pri cikličkom opterećenju. Prikazani su proračunski modeli zamora prema fib Model Code 2010, ACI 215 i JSCE smjernicama. Rezultati proračunskih modela uspoređeni su s rezultatima eksperimentalnog istraživanja. Uočeno je da, u pravilu, svi proračunski modeli podcjenjuju eksperimentalno određenu otpornost betona pri zamoru. Dan je prijedlog korekcije fib Model Code modela.

Primjena recikliranih čeličnih vlakana u betonskim elementima izloženima zamoru

Dodavanjem celicnih vlakana u beton poboljsavaju se njegova svojstva pri zamoru. Opisana su eksperimentalna istraživanja betonskih elemenata s recikliranim celicnim vlaknima pri ciklickom opterecenju. Prikazani su proracunski modeli zamora prema fib Model Code 2010, ACI 215 i JSCE smjernicama. Rezultati proracunskih modela uspoređeni su s rezultatima eksperimentalnog istraživanja. Uoceno je da, u pravilu, svi proracunski modeli podcjenjuju eksperimentalno određenu otpornost betona pri zamoru. Dan je prijedlog korekcije fib Model Code modela.Dodavanjem čeličnih vlakana u beton poboljšavaju se njegova svojstva pri zamoru. Opisana su eksperimentalna istraživanja betonskih elemenata s recikliranim čeličnim vlaknima pri cikličkom opterećenju. Prikazani su proračunski modeli zamora prema fib Model Code 2010, ACI 215 i JSCE smjernicama. Rezultati proračunskih modela uspoređeni su s rezultatima eksperimentalnog istraživanja. Uočeno je da, u pravilu, svi proračunski modeli podcjenjuju eksperimentalno određenu otpornost betona pri zamoru. Dan je prijedlog korekcije fib Model Code modela.

LOAD BEARING CAPACITY OF THE GLASS RAILING ELEMENT

In this paper some basic physical and mechanical properties of glass as structural material are presented. This research is about specifically manufactured glass railing element that will be a part of a pedestrian bridge construction in Zagreb, Croatia. Load bearing capacity test of the glass railing element is conducted within the Faculty of Civil Engineering in Zagreb and obtained experimental results are discussed and compared to the ones provided by the numerical model. Taking into account the behaviour of laminated glass and results of experimental and numerical testing, glass railing element can be regarded as safe.

Ductility analysis of laminated timber beams of small section height

Svrha je rada analizirati odnosno utvrditi primjenjivost modela koji uzimaju u obzir duktilnost drvenih elemenata pri savijanju. Ispitani su i prikazani gredni elementi male visine, dakle elementi kod kojih je raspon visestruko veci od visine. Osim ispitivanja grednih elemenata, dani su rezultati ispitivanja mehanickih karakteristika osnovnog materijala i prikazana su ispitivanja provedena metodom konacnih elemenata (numericki modeli). Numericki modeli napravljeni su u programskom paketu Abaqus.