混凝土的细骨料历来以河砂为主,但由于长期取用,日见枯竭,而混凝土的需要量又迅速增加,所以近年来也大量使用海砂、山砂、碎砂等作为混凝土的细骨料,其中在日本使用海砂的比例最高。所谓海砂,一般是指河口砂、海滨砂、海底砂的总称。海砂受海水影响,必然带有盐分。海水中含的盐类有氯化钠、氯 Concrete fines are historically dominated by river sand, but due to long-term access, daily depletion has dried up, and the demand for concrete has rapidly increased. Therefore, in recent years, sea sand, mountain sand, and crushed sand have also been used as concrete fines. Aggregate, which has the highest proportion of sea sand used in Japan. The so-called sea sand generally refers to estuary sand, beach sand, and sea sand. Sea sand is affected by seawater and it must have salt. Salts contained in seawater include sodium chloride and chlorine