Effect of stone dust in concrete using fly ash in cement / Mohammad Abdul Azim bin Haji Ali

Dissertation submitted to Universiti Teknologi Brunei in partial fulfillment of the requirements for the degree of Bachelor of Engineering

Abstract

Nowadays High Performance Concrete has been used widely in the construction industry worldwide. However Brunei is gradually adapting the use of fly ash in construction such as UBD swimming pool, Temburong Bridge and Pulau Muara Besar Bridge. For a strong and durable structure it appears that High Performance Concrete is a better choice. Normal and special materials are used to make these specially designed concrete that must meet a combination of performance requirements.

This report is written based on the practical work as well as the results obtained by the application of project work "EFFECT OF STONE DUST IN CONCRETE USING FLY ASH IN CEMENT". The experimental investigation is carried out to evaluate the slump value, compressive strength, water absorption and density of M30 grade concrete in which Ordinary Portland cement was replaced with 25% of low calcium fly ash by weight which were further modified by partially replacing natural sand with two percentages (25% & 50%) of stone dust/quarry dust. The compressive strength was determine at the age of 3, 7, 28 and 56 days.

As expected from the investigation by many researchers, the early compressive strength of sample H1, H2 and H3 which contain pulverized fly ash are lower than control mix sample CI (without fly ash). At the age of 7 days, the compressive strength of sample H2 have surpassed compressive strength of sample C1 by 0.3% of its value. The compressive strength of sample H1, H2 and H3 continue to develop and exceed sample C1 by more than 25% of its value at the age of 56 days.

Other tests such as slump test were conducted on fresh concrete while water absorption test and density test were conducted on hardened concrete. The slump values obtained were within the targeted value with sample HI as the highest slump. Water absorption test and density test on the other hand shows that sample H2 and H3 have the highest value obtained respectively when compared to control mix and other sample. The test results shows that the combination of stone dust/quarry dust and low calcium fly ash give a satisfactory and excellent performance due to the efficient microfilling and the pozzolanic activity. The details of the investigations along with the list of studies by many researchers are presented in this report.

Thesis is also available in CD and is not for loan or reference use.

Includes bibliographical references and appendices