سينا ندرمحمدي

Climate and environmental temperature changes are among the most significant challenges affecting the behavior of materials. These changes can result in extreme temperature fluctuations increased sandstorms, and consequently a rise in sulfate attacks as well as intensified freeze-thaw cycles. One of the infrastructures constantly exposed to climatic changes is railway tracks. In ballasted railway tracks ballast is affected by various factors such as freezing and thawing, extreme cold or heat and attacks by different sulfate salts, all of which can accelerate the degradation of ballast aggregates. Therefore, considering that a substantial portion of railway maintenance costs is due to ballast layer degradation this study aims to investigate the impact of climatic changes and environmental temperature conditions on the durability of ballast aggregates through laboratory experiments. In this regard the present project examines the durability behavior of ballast aggregates under four different environmental temperature conditions: warm temperatures up to +100°C, cold temperatures down to -20°C, freeze-thaw cycles and a corrosive sulfate environment. To achieve this, ballast aggregates were placed under each of these simulated conditions and their durability was analyzed and eva‎luated by measuring changes in various indices including Los Angeles abrasion, micro-Deva‎l abrasion, impact, crushing and fracture of the aggregates. The laboratory results indicate that the overall trend of index changes in cold, warm, sulfate attack, and freeze-thaw conditions led to an average reduction of 50%, 20%, 40%, and 35% in durability indices, respectively. This demonstrates the significant impact of environmental temperature conditions on the durability of ballast aggregates.

بالاست , دوام سنگدانه ها , تغييرات دمايي , شرايط محيطي

ballast , ballast durability , thermal change , environmental condition

Sina Nader Mohammadi

Dr. Hamidreza Heidari