APPLICATION OF PERVIOUS CONCRETE IN ROAD CONSTRUCTION

U radu je dan pregled svojstava poroznog betona te prikazane prednosti njegove uporabe u kolničkim konstrukcijama. Pripremljene su dvije mješavine poroznog betona i mješavina referentnog betona, uobičajeno korištena za izradu betonskih kolničkih konstrukcija, te uspoređena njihova svojstva: konzistencija, tlačna i vlačna čvrstoća, poroznost i gustoća, dinamički modul elastičnosti te propusnost. Procijenjena je i mogućnost njihove primjene u betonskim kolničkim konstrukcijama, sukladno uvjetima propisanim u Općim tehničkim uvjetima za radove na cestama. Mješavina s malim udjelom cementa i dodatkom superplastifikatora nije udovoljila najmanje zahtijevanoj poroznosti i propusnosti za porozne betone. Nasuprot tome, mješavina s većim udjelom cementa i bez dodatka superplastifikatora ocijenjena je kao porozna, no ne posjeduje tlačnu čvrstoću potrebnu za kolničke konstrukcije. Stoga, potrebno je daljnja istraživanja usmjeriti ka poboljšanju tlačne čvrstoće mješavina.This paper presents an overview of the properties of porous concrete, and the advantages of its use in pavement structures. Two mixtures of pervious concrete and a reference concrete mixture commonly used for concrete pavements are prepared and their properties compared: consistency, compressive and flexural strength, porosity and density, dynamic modulus of elasticity, as well as permeability. The possibility of their application in concrete pavements is estimated in accordance with the requirements given in General technical conditions for roadworks. Mixture with a small amount of cement and addition of superplasticizer did not meet minimum porosity and permeability required for pervious concrete. In contrast, a mixture with a higher amount of cement and without the addition of superplasticizer was evaluated as pervious one, but does not have a compressive strength required for road construction. Therefore, it is necessary to direct further research towards improving the compressive strength of mixtures of pervious concrete

INFLUENCE OF AGGREGATE TYPE AND SIZE ON PROPERTIES OF PERVIOUS CONCRETE

Porozni beton ima sve veću primjenu u cestogradnji zbog njegove vrlo visoke propusnosti koja daje veliku prednost u odnosu na uobičajeni beton zbog smanjenog površinskog otjecanja vode s kolnika i parkirališta te smanjeni utjecaj toplinskih otoka i buke od prometa. Nažalost, zbog smanjenje čvrstoće porozni beton ima ograničenu primjenu u kolničkim konstrukcijama prometnih cesta. Cilj ovog istraživanja je poboljšanje svojstva čvrstoće uključivanjem različitih vrsta agregata i različitih veličina zrna agregata. Ispitani rezultati pokazuju da je moguće proizvesti beton sa prihvatljivom propusnosti i čvrstoću kroz kombinaciju vrste agregata i veličine zrna agregata.Pervious concrete has been increasingly used in road construction because of its very high permeability, which gives a great advantage over normal concrete due to reduced surface runoff water from the road and parking and reduced heat island effect and the noise of traffic. Unfortunately, due to the reduction in strength pervious concrete has limited application in pavement structures busy roads.The aim of this research is to improve the strength properties of the inclusion of different types of aggregates and various sizes of aggregate. Examined results show that it is possible to produce concrete with acceptable permeability and strength through the combination of aggregate type and size of aggregate