The Effects of Seawater on the Durability of Hydrotechnical (Concrete) Structures in the Port of Klaipeda / Jūros Vandens Poveikis Klaipėdos Uosto Hidrotechninių Statinių (Betono) Ilgaamžiškumui

Abstract

Seawater has a significant impact on hydrotechnical concrete structures in the Port of Klaipeda. This factor must be properly examined and evaluated designing reinforced concrete structures exploited in seawater. The basic aim of research is to assess the effects of seawater on concrete and to form an algorithm for studying the durability of hydrotechnical structures affected by seawater. The conducted investigation showed the impact of seawater on hydraulic engineering (concrete) structures.Serious defects are caused by corrosion in hydrotechnical concrete. The key factors indicating the durability index of hydrotechnical concrete include damage to the concrete due to environmental, mechanical and physical-chemical effects.Physical-chemical environmental effects occur due to changes in temperature, the speed of the wind and fluctuations in the sea-level. Multiple environmental impacts can simultaneously affect hydrotechnical concrete.Mechanical external effects occur due to constant stevedoring works and vessels moored at the Port of Klaipeda.

Influence of Mineral Additives on Environmental Resistance of Concrete

“…Seawater action on concrete structures can cause concrete deterioration in humid and aggressive environments. In this case corrosion and destruction of concrete structures can take place [2], [3]. Typical damages of concrete surfaces in Klaipeda Sea Port structures are displayed in Fig.…”

“…Klaipėda City and the territory of Klaipėda County is attributed to the western climatic region of Lithuania with characteristic western winds and moist sea air where winter temperature is higher than in other climatic zones of Lithuania due to the ice-free sea [2], [4]. Scientists [5], [6] have measured air temperature variations per day within the climatic zone of Lithuania, air temperature around 0 °C may fluctuate in Klaipėda from 3.6 °C to 11.8 °C for several consecutive days.…”

“…Scientists examined quantities of salts contained in water which came into contact with hydraulic concrete [2], the values were as follows: SO4 Researchers T. C. Powers and R. A. Helmuth during their analysis of the structural degradation of concrete due to cyclic freezing and thawing processes in the water-saturated state have established that movements of unfrozen water in concrete pores towards frozen areas under pressure in capillary pores are one of the most important concrete-degrading effects during freezing and thawing, because pressure force depends on the state of water in pores. Hydraulic pressure can cause cracking of concrete [13].…”