During their use reinforced concrete structures are exposed to external influences. Nowadays, the reducing effect of these influences is usually ensured by secondary (barrier) protection. At present, coatings based on organic substances are commonly used. However, these types of secondary protection show substantial limits under extreme conditions. A method that has considerable potential to eliminate these disadvantages includes the application of secondary protection based on alkali-activated materials or geopolymers. This paper is focused on the development and optimisation of secondary protection (coating, plaster) based on alkali-activated materials intended for reinforced concrete structures to be exposed to highly chemically aggressive environments. Keywords: coatings, alkali-activated substances, extreme conditions, agressive environment, durability of structures Med uporabo so armirane betonske konstrukcije izpostavljene zunanjim vplivom. Danes se zmanj{anje vpliva teh u~inkov zagotovi z uporabo sekundarne za{~ite (prepreka). Obi~ajno se uporabljajo premazi na osnovi organskih snovi. Vendar pa so te vrste sekundarne za{~ite precej omejene pri ekstremnih pogojih. Metoda s potencialom da odpravi te pomanjkljivosti, vklju~uje uporabo sekundarne za{~ite na osnovi alkalno-aktiviranih materialov ali geopolimerov.^lanek obravnava razvoj in optimiranje sekundarne za{~ite (premaz, omet) na osnovi alkalno aktiviranega materiala, namenjenega za armirane betonske konstrukcije, ki bodo izpostavljene kemijsko mo~no agresivnemu okolju. Klju~ne besede: premazi, alkalno-aktivirane snovi, ekstremni pogoji, agresivno okolje, zdr`ljivost konstrukcij