The investigations of concretes leak-proof, freeze-proof and chemical corrosion-proof have been confirmed that the new alkali-slag concrete has possessed a good merit of durability.
抗渗、抗冻及抗化学侵蚀试验表明，新型碱矿渣混凝土具有优异的耐久性能。
2
Via experiment and analysis, the technical specifications of the freezeproof and electrical heating device for plug doors as well as the inspection requirements are put forward.
通过实验分析，提出了塞拉门防冻电热装置的技术条件和检验要求。
3
The principles, structure and mode of the freezeproof and electrical heating device for plug doors are described.