Bridge over river Zrmanja in Obrovac was built at the beginning of the 20th century as an arch bridge. During the World War II it was destroyed, and then after the war renovated but with different static system. It is a reinforced concrete structure with maximum span of 42 meters. After 55 years in use in severe climate, typical damages result from reinforcement corrosion caused by carbonation and frost cycles. Bridge lies on the one of the most frequent traffic routes, so it was necessary to do repair works under traffic. Asphalt and insulating layer were removed and replaced with polymer modified concrete overlay. As compared to similar solutions in other countries where high strength concrete is mostly used, the high performances pertain to the durability properties, with specific strength 40 MPa. For improvement of mechanical properties high performance concrete was modified with styrene-butadiene latex and fiber reinforcement and designed for the following properties and purposes: satisfactory resistance to freezing and deicing chemicals, to serve as the impermeable overlay replacing the insulation, resistance to wear and abrasion, smaller risk of crack appearance, higher resistance to chloride ions penetration. Surface exposed to traffic load was impregnated with styrene-butadiene latex to improve its durability and mechanical properties.
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