The crushed stones that line railroad tracks are collectively called track ballast.

铁路轨道上的碎石统称为轨道压碴。

Sometimes, the stones are replaced with a new set of crushed stones.

有时，这些石头会被替换成一套新的碎石。

The crushed stones in the track ballast offer a larger surface area than a flat plane.

轨道道砟中的碎石比平面提供了更大的表面积。

Anti-slip surfaces could be incorporated, too, including crushed stones which are traditionally used to dress road surfaces.

塑料公路还能装上防滑表层，包括传统用于铺设路面的碎石子。

First, mark the sides of the path by dropping two lines of crushed white stone on the ground.

首先，往地面上扔落两排白色的碎石来标记小径的两侧。

They use a soil microbe to transform loose aggregates, like sand or crushed stone, into a biofabricated, or biocement, brick.

他们使用一种土壤微生物，将砂砾或碎石之类的碎颗粒转换成生物制造的砖头，又称生物水泥砖。

By adding rubber " crumbs" , reclaimed from shredded tyres, to the bitumen and crushed stone used to make asphalt, engineers are designing quieter streets.

在沥青和碎石里添加从轮胎碎片中回收的废胶末，再铺成柏油路，这样工程师可以设计出更加安静的街道。