定形相变材料具有在周围温度变化时通过自身相转变吸收或释放热量的能力,同时使用过程中能够保持较好的强度和稳定性,该种材料掺入寒区路基土体中可以调节路基温度场。研究了冻融循环作用下一种商用定形相变材料对土热学和力学性能的影响,通过对冻融循环作用下的不同掺量定形相变材料的土体进行导热系数试验、温度监测试验和无侧限抗压强度试验,并对定形相变材料进行分析。结果表明:定形相变材料的相变焓值大于200J/g,定形相变材料的掺入使土体的导热系数增大,解冻时长增加,减小了冻融循环作用对土体强度的破坏,15次冻融循环作用下6%掺量的土体强度衰减最小,土体的热学和力学性能的变化与定形相变材料的掺量密切相关。
The shape-stabilized phase change materials (SPCMs) have the ability to absorb or release heat through their own phase transition when the ambient temperature changes,while maintaining good strength and stability in the process of use.The temperature field of roadbed can be adjusted when the material is added into the soil of roadbed in cold region.Under the action of freeze-thaw cycles,the effects of commercial SPCMs on the thermal and mechanical properties of soil were investigated,the thermal conductivity test,temperature monitoring test and unconfined compressive strength test were conducted on soils with different dosage of SPCMs,and the SPCMs was further analyzed.The results showed that the enthalpy value of SPCMs was greater than 200J/g,and the incorporation of the SPCMs enhanced the thermal conductivity of the soil,increased the thawing time,and reduced the damage to the strength of the soil caused by freeze-thaw cycles.Under 15 freeze-thaw cycles,the strength attenuation of the soil with the dosage of 6% was the smallest.The change of thermal and mechanical properties of soil was closely related to the amount of SPCMs.
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基金资助
中国科学院科技服务网络计划项目(KFJ-STS-ZDTP-037)
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