Influence of superplasticizer on performance of cement – bottom ash concrete

Abstract

The issue related to disposing waste material from industries has become one of the major environmental, economic and social problems. However, natural resources consumed worldwide, while at the same time increased amount and type of the waste material has resulted in waste disposal crisis with a growing consumer population. Therefore, the solution to this crisis is recycling waste into useful materials. In this project, Municipal Solid Waste Incineration (MSWI) by product which is bottom ash is used as partial replacement in cement. However, its properties as water absorbent become the issue for concrete strength. This research paper is to investigate the influence of superplasticizer on performance of cement-bottom ash concrete and designed for strength of 20 MPa at 28 days will be evaluated for its early stage properties. Superplasticizer is used to reduce water in cement while keeping up a consistent workability. The percentage of replacement in cement is by 0% (control), 10% and also 10%, 20% and 30% with addition of 0.30% by weight of cement of superplasticizer. In order to achieve the objective, few tests were carried out including slump test, density test, water absorption test and compression test. The result of this research indicates that 10% of replacement of bottom ash with superplasticizer shows highest compressive strength with 33.215 MPa with density 2417 kg/m3, water absorption of 1.41% and 122 mm for slump loss at 28 days. This study proved that the addition of superplasticizer can increase the workability and strength of concrete containing bottom ash as replacement for cement.