According to maintenance Engineers of City of Vantaa and Helsinki there has been problems in durability of concrete block pavements in recent years. Concrete block pavers (CBP) have deteriorated fast by wearing down just in 2 to 3 years. These observations have led to believe that the material quality of CBP's have declined during the last twenty years. In the 1980's the use of CBP's was justified by studies, which indicated that concrete block pavers have longer life and better abrasion resistance than asphalt concrete. Objectives of the thesis were to determine what factors affect on abrasion resistance of CBP's and what types of damages occur in concrete block pavements. Research was conducted having in-situ inventory study of damaged pavements and testing abrasion resistance of CBP's in laboratory. Abrasion resistance standard criteria were assessed based on the laboratory tests. In addition, a test area was constructed in Vantaa where construction practices and quality of delivered materials were studied in more detail.Based on the literature survey abrasion resistance of CBP's are particularly affected by cement content, strength of cement, water-cement ratio, granularity, hardness of aggregate and curing time. Standard determines that the abrasion resistance of CBP should be tested with the wide-wheel abrasion test or the Böhme-test. Neither of the tests is applicable to determine the studded tire abrasion resistance. In addition, the weather resistance test, which is used for testing chemical and freeze-thaw resistance, is for the Central European conditions and does not address conditions in Finland. Based on visual inspections of the trafficked areas, the biggest problem with concrete block pavements was peeling of the surface of the CBP. CBP's used in test area decayed only after six months from construction, which is less than is thought. According to manufacturers and maintenance engineers the main cause for this wear was studded tire abrasion aggravated by the maintenance salt and freeze-thaw cycles during winter time.Laboratory tests were carried out by the Böhme apparatus and a Prall apparatus, which is a standard device for testing asphalt concrete's abrasion against studded tires. Most of the CBP samples did poorly on the Prall test and there were large differences among the abrasion values. Only two CBP types passed the lowest abrasion resistance criteria set for asphalt concrete. In Böhme-test, the only CBP type suitable for trafficked areas didn't pass criteria set in the EU-standard. In addtition to CBP's, polymer concrete blocks (PC) were tested. In PC blocks polymer resin serves as a binder instead of cement paste. PC blocks did very well on both tests; the abrasion values of PC blocks were half of the values of the best CBP's. Based on the tests carried out for this work, Prall apparatus is suitable for testing CBP's, but further tests are needed.
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