Emeritus Professor Hokkaido University, Sapporo, Japan.
Department of Health and Psychosocial Medicine, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan.
PLoS One. 2021 May 13;16(5):e0249761. doi: 10.1371/journal.pone.0249761. eCollection 2021.
In concrete structures (concrete), damage from cracks, deterioration, amorphization, and delamination occur in some structures, causing disaggregation (concrete changed to very fine particles) and hollowing out of the concrete. In concrete pavements, damage from large amounts of pop-out of aggregate occurs from the surface of the concrete pavement 4-5 hours after spraying of snow melting agent on the surface of the pavement. The damage from disaggregation, blistering, cracks, and peeling-off of a surface course have also been observed in asphalt runways and highways. The damage from disaggregation, cracks and pop-out of aggregate in asphalt pavements and concrete structures have long been seen as strange and unexpected and have defied explanation. As a result of examinations in various experiments, it was concluded that all of the unexplained kinds of damage of both asphalt pavements and concrete structures were caused by Trace Quantities of Organic Matter (TQOM), Air Entrained (AE) water reducing agent in air and/or cement, and surfactant in snow melting agent. The emission sources of TQOM and these organic substances were also identified by chemical analysis for these unexpected and unexplained phenomena. The TQOM includes phthalate compounds (phthalates in the following), amine compounds, phosphate compounds, snow melting agent and Sodium Polyoxyethylene Nonyl phenyl Ether Sulfate (SPNES). SPNES is a surfactant in windshield washer fluid for automobiles. We found that the water content and content of organic matter in damaged asphalt pavements and concrete structures are also important indicators for the damage. Further, a new evaluation method for amorphization was proposed in this study and it appears suitable for evaluating the safety of concrete structures along roads which were exposed to TQOM in severely air-polluted environments.
在混凝土结构（混凝土）中，一些结构会出现裂缝、劣化、非晶化和分层等损伤，导致混凝土解体（混凝土变成非常细的颗粒）和空心化。在混凝土路面中，大量骨料弹出的损伤会在路面表面喷洒融雪剂后 4-5 小时从混凝土路面表面发生。在沥青跑道和高速公路上，也观察到表面层的离析、起泡、裂缝和剥落损伤。沥青路面和混凝土结构中骨料的离析、裂缝和弹出损伤长期以来一直被视为奇怪和意外的现象，并且无法解释。通过各种实验的检查，得出结论，所有未解释的沥青路面和混凝土结构的损伤都是由痕量有机物（TQOM）、含空气的引气减水剂和水泥中的表面活性剂以及融雪剂中的表面活性剂引起的。通过对这些意外和无法解释的现象进行化学分析，还确定了 TQOM 和这些有机物质的排放源。TQOM 包括邻苯二甲酸酯化合物（以下简称邻苯二甲酸盐）、胺类化合物、磷酸盐化合物、融雪剂和聚氧乙烯壬基苯基醚硫酸酯（SPNES）。SPNES 是汽车挡风玻璃清洗液中的一种表面活性剂。我们发现，受损沥青路面和混凝土结构中的水分含量和有机物含量也是损伤的重要指标。此外，本研究提出了一种新的非晶化评价方法，该方法似乎适合评估在严重空气污染环境下暴露于 TQOM 的道路沿线混凝土结构的安全性。
