Influence of physical and geometrical properties of granite and limestone aggregates on the durability of a C20/25 strength class concrete F. Pacheco Torgal a, * , J.P. Castro-Gomes b,1 a Castelo Branco Polytechnic Institute, Department of Civil Engineering, 6000 Castelo Branco, Portugal b University of Beira Interior, Department of Civil Engineering, 6200 Covilha ˜ , Portugal Received 6 January 2004; received in revised form 10 January 2005; accepted 20 January 2005 Available online 12 April 2005 Abstract This paper presents an experimental study to evaluate the influence of physical and geometrical properties of granite and lime- stone aggregates on the durability of a C20/25 strength class concrete. Different granite and limestone aggregates were collected from seven quarries. Physical, geometrical and mechanical properties of aggregates as well as the rock weathering state were quantify by several tests such as, abrasion, surface hardness, uniaxial compressive strength, ultrasonic pulse velocity, water absorption by cap- illarity, vacuum water absorption and oxygen permeability. Using aggregates from each quarry, several C20/25 strength class concrete mixes have been produced, with the same workability and volume proportions. Concrete specimens have been cured under water for 90 days; after that time concrete durability param- eters were obtained through tests such as, vacuum water absorption, capillarity water absorption, water permeability and oxygen permeability. Relevant statistical correlations have been obtained between absorption and permeability test of rock material and rock deteri- oration state (weathering). Valid statistic correlation was also obtained between durability parameters as well as among aggregates geometrical properties and concrete durability parameters. Ó 2005 Elsevier Ltd. All rights reserved. Keywords: Aggregate; Permeability; Absorption; Durability; Concrete 1. Introduction Concrete durability can be defined as the ability to re- sist through time to the attack of environmental, physi- cal and chemical aggressive conditions. There is not at present a test which can quantify with no doubt this property: a test that could define a dura- bility class, as easy as concrete compressive strength and its resistance class are defined. Only some tests and specifications are able to quantify some concrete parameters related to durability. The BS 8110 [1] speci- fies a minimum amount of cement and a maximum W/C ratio, however, this is only a way to minimize concrete porosity and a weak one. This specification does not give information on concrete porosity once it has been mixed and cast. The same happens with other regula- tions and specifications, as the Japanese Standard [2] which considers the service life of concrete more depen- dent on the concrete cover thickness than on any other concrete parameter. 0950-0618/$ - see front matter Ó 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.conbuildmat.2005.01.063 * Corresponding author. Tel.: +351 272 339300; fax: +351 272 339399. E-mail addresses: fernandotorgal@est.ipcb.pt (F. Pacheco Torgal), castro.gomes@ubi.pt (J.P. Castro-Gomes). 1 Tel.: +351 275 329990; fax: +351 275 329969. Construction and Building Materials 20 (2006) 1079–1088 Construction and Building MATERIALS www.elsevier.com/locate/conbuildmat