gunite covering是什么意思

用法例句

Finally shotmortar support was taken.

最后采用了砂浆喷层支护，控制了洞室坍方问题。

Experiment study on the effects of surface mortar layer to the resistance of concrete to chloride ion penetration;

表面砂浆层改善混凝土抗氯离子渗透性能的试验研究