Timber iQ June - July 2019 // Issue: 44 | Page 34

FEATURES Timber planks stacked neatly ready to be used. ‘Coal cannot be mined from underground without supporting the roof and often the sides of the mining shafts. For this use, wood is a valuable resource,’ the article reads. The first one is a round prop which has the main purpose of supporting mine roofs. The article describes how the prop is loaded in a perpendicular angle to the roof and the floor to achieve maximum strength. ‘Props are used in faces, mine entries, and along haulage corridors,’ the article explains. Next it describes sawn props, which have a similar purpose to round props. The difference is that they have more of a permanent function in that they are often set in mine corridors for up to 10 years. They are also the main preference for mines because 32 JUNE / JULY 2019 // Timber is mostly used to provide roof support in an underground mine. www.timberiq.co.za