00:00Welcome to Learn with Cemex.
00:03At Cemex we want to share our years of experience and give you some tips on concrete quality control.
00:11We will start with a common test, the slump or consistency of concrete ASTMC 143 or NTC 396.
00:22To do this, we need to take a sample and homogenize it with a shovel.
00:26Remember not to let more than 5 minutes elapse between taking the sample and starting the test.
00:35We will need a standard-sized conical mold, a smooth rod with a hemispherical tip, a spoon, and a measuring tape.
00:45Moisten the mold and place it on a horizontal surface.
00:48Rest both feet on the supports and with a spoon begin filling in 3 layers of equal volume.
00:55Between each layer, it performs 25 insertions.
01:00Remember to leave an excess on the last layer so that it can be leveled after the inserts.
01:07Without moving the cone, clean up any spills around it that could affect the test.
01:12Place both hands on the handles.
01:15Pull your feet back until you are in a stable position.
01:18And lift the cone vertically in a time of 3 to 7 seconds.
01:25Place the cone upside down next to the concrete sample and the rod horizontally supported.
01:32about this.
01:33Measure the distance between the bottom of the rod and the projection to the center of the cone.
01:39This test has an accuracy of plus or minus one inch.
01:45Some common mistakes are
01:47First, take the reading at the highest point of the cone, not at the center.
01:55Second, take the reading even when the cone has broken.
02:00Third, take the reading from the top of the rod or when the concrete is still in motion.
02:07And fourth, not considering the accuracy of the test.
02:13At CEMEX we work to achieve products with the highest quality standards.
02:18Stay tuned for the next video on how to take a concrete sample according to ASTM C172 or NTC 454.
02:29CEMEX. Building a better future.
02:32To get a quote for our products, call us at 236.
Comments