To use concrete returned from job sites, a method to maintain the fresh properties of the returned concrete for a long time was studied by adding a retarder to stop cement hydration temporarily and adding an activator to the concrete to reuse next day...
To use concrete returned from job sites, a method to maintain the fresh properties of the returned concrete for a long time was studied by adding a retarder to stop cement hydration temporarily and adding an activator to the concrete to reuse next day in the same manner as an ordinary concrete.