20/03/2012
higgens concrete


started in the e shed talked about what was going on today. made our way to higgens concrete contractors and met aaron curry he started the visit with an intro about what makes a god concrete. cement agrogates/stones and water. he told us about workabilaty which is how easy the concrete is to work with and use. we moved on to the testing. we were showed to to do a compression test and a slump test. the compression test cosited of a worker filling a template in 3rds an prodding it down every 3rd of the cylinder we were told then it was sent off to a lab an tested using compression to see how strong that batch of concrete is. the slump test was pretty much much the same but it was done in a cone shape template. a worker filled the cone in 3rds again prodding it down 25 prods to every fill. he then slowly but with a consistant pace pulled the cone off the concrete turned it upside down an measurement from the top of the cone to the highest point of the concrete an that determined the slump of the concrete. we moved onto what kind of chemicals can be added to slow or speed up the chemical reaction in the concrete to make it set faster or keep it wet longer. accelerator to make it set faster and retarders to slow the process down. also fibres that can be added to concrete that needs to be poured on a slope to hold it together/ keep it in place for example a driveway.