| 摘要 |
<p>The concrete kerb for public or private use is made by continuous casting in situ by a machine with sliding shuttering. It has a reflective surface formed by encrustation with glass micro-balls having a refraction index of between 1.504 and 1.535 and a diameter of between 125 and 991 microns, depending on the function of the kerb. The glass micro-balls are encrusted in the concrete in contact with one another, and cover all of the kerb's visible faces. They are applied to the freshly-cast concrete by a hopper and metal plate attached to the shuttering.</p> |
