关键词: 铁尾矿砂, 力学性能, 吸水率, 碳化深度, 渗透深度, 放热速率, 放热量

Abstract: In order to explore the influence of iron tailing ore addition on the mechanical properties and durability of iron tailing concrete， the compressive strength， impact resistance， impermeability and hydration properties of concrete with different iron tailing addtions were investigated by taking iron tailing ore from Tangshan as aggregate. The results show that: ①With the increase of iron tailing sand content， the compressive strength and flexural strength of concrete both increase first and then decrease. The compressive strength is the highest when the iron tailing sand content is 10%， and the flexural strength is the highest when the iron tailing sand content is 20%. The impact energy and fracture absorption energy of concrete tend to increase first and then decrease. When the iron tailing sand content is 20%， the impact energy and fracture absorption energy reach the maximum value. ②As the content of iron tailings increases， the water absorption of concrete gradually decreases. The carbonation depth and penetration depth of concrete first decrease and then increase. When the iron tailing sand content is 20%， the carbonization resistance and impermeability of the concrete are the best. ③As the hydration reaction continues， the heat release rate of hydration shows a trend of increase， decrease， increase， decrease， and decrease. However， the hydration heat release rate of concrete under the same hydration time decreases with the increase of iron tailing sand content. With the extension of the hydration time， the heat release of concrete hydration shows an increasing trend. With the increase of iron tailings sand content， the lower the hydration heat of concrete under the same hydration time.

Key words: iron tailings, mechanical properties, water adsorption, carbonation depth, water seepage depth, hydration heat release rate, hydration heat release