concrete running surface的意思|示意

Avoid concrete as much as possible: It's about 10 times as hard as asphalt, and is a terrible surface for running.

尽量避免水泥路面：其硬度是沥青路面的十倍，是非常不适合跑步的路面。

After running for 30 years, carbonization, cracks and corrosion of steel have occurred on the surface of the concrete of Sanhe navigation lock which was built in 1970.

三河船闸建于1970年，经过三十多年的运行，混凝土表面出现碳化、裂缝和钢筋外露锈蚀。