Abstract
It is always required for fresh concrete to provide a proper flowability with least segregation. Mix proportion of concrete to satisfy such requirements is usually determined by trial and error. The authors propose a mechanical model on bleeding taking account of the behavior of cement particles under the usage of superplasticizer. Experimental test was conducted on mortar with parameters of three levels of W/C, three types of sand and four levels of mortar flow. The proper amount of superplasticizer was determined so as to satisfy the target value of mortar flow in each case. Comparing with experimental results, it is found that the proposed model can indicate how to determine a proper mix proportion of mortar with least bleeding under given conditions of mortar flow, W/C, properties of sand and cement.
