Durability of materials based on a polymer-silicate matrix and a lightweight aggregate exposed to aggressive influences combined with high temperatures

Abstract

The paper presents the results and findings of the research focused on an examination of progressive degradation of newly developed composite materials. These materials consisted of a polymer-silicate matrix and a mix of fillers with a considerable proportion of a porous aggregate. The matrix also contained a larger amount of alternative raw materials, in particular hightemperature fly ash and blast furnace slag. Prepared mixes were tested after different periods of exposure to an aggressive environment -for 45 d and 90 d (50 and 100 cycles). First, after 45 d and 90 d, reference materials (i.e., those not exposed to aggressive influences) were tested. In parallel, tests were carried out with materials exposed to a solution of chloride ions and subjected to cyclic freeze and thaw. The last mode of testing in this research included materials exposed to cyclic freeze and thaw, chloride-ion solution and the consequent thermal load of up to 1000°C. The level of degradation was evaluated by means of physico-mechanical, physico-chemical and microstructural test methods. It was found that the exposure to cyclic freeze and thaw, water and chloride ions has no considerable influence on the reduction of the thermal resistance of the developed mix designs of polymer-silicate-based composites. Keywords: durability, porous aggregate, polymer-silicate matrix, long-term exposure, chloride ions, water, frost, fire, microstructurê lanek predstavlja rezultate in izsledke raziskave, osredoto~ene na preverjanje napredujo~ega slab{anja na novo razvitih kompozitnih materialov. Ti materiali so sestavljeni iz polimer-silikatnih matric in me{anice polnil z znatnim dele`em poroznih agregatov. Matrica je vsebovala tudi ve~jo koli~ino alternativnih surovih materialov, visokotemperaturni dimni{ki pepel iǹ lindro. Pripravljene me{anice so bile testirane po razli~nih~asih izpostavljanja agresivnemu okolju -45 d in 90 d (v 50 in 100 ciklih). Najprej so bili, po 45 d in 90 d, testirani referen~ni materiali, tisti, ki niso bili izpostavljeni agresivnim vplivom. Vzporedno pa so bila izvedena testiranja materialov, ki so bili izpostavljeni raztopini kloridnih ionov ter nato cikli~no zamrznjeni in nato staljeni. Zadnji na~in testiranja v tej raziskavi je bilo izpostavljanje materialov cikli~nemu zamrzovanju in taljenju, kloridni raztopini ionov in ter toplotni obremenitvi do 1000°C. Stopnja degradacije je bila ocenjena glede na fizikalno-mehanske, fizikalno-kemi~ne in mikrostrukturne testne metode. Ugotovljeno je bilo, da izpostavljenost cikli~nemu zamrzovanje in taljenju, vodi in kloridnim ionom, nima ve~jega vpliva na zmanj{anje termi~ne odpornosti na razvite me{anice iz polimer-silikatnih kompozitov.