Prediction model of air-borne salt distribution in the coastal region of northern Taiwan

Abstract

Taiwan is located in subtropical region, where temperature and humidity are relatively high all year round. Besides, theisland is surrounded by ocean that the air-borne salt (ABS) attack is one of the major concerns for concrete structures. In this paper, a prediction model for the distribution of air-borne salt in the coastal region of northern Taiwan is proposed based on the result of ABS measurement at 38 sites near a period of four years. The ABS content was calculated monthly based on the salt concentration, water amount, time, and area of entrance. The monthly measured ABS of the entire year were then analyzed to obtain the characteristics of ABS attack in different conditions. By using the measurements of Chin-Shan, Keelung, and Lung-Fong sites, 480 data in total were analyzed by the proposed prediction model. The distance to seashore, wind direction, effective wind velocity, and effective precipitation are the primary factors for the ABS distribution.