Mechanical behaviour of self compacting concrete: Effect of wood ash and coal ash as partial cement replacement

Self-compacting concrete (SCC) is an innovative construction material in the construction industry. It is a highly fluid and stable concrete that flows under its own weight and fills completely the formwork. The SCC requires high powder content (mainly of cement) up to 600kg/ to achieve its properties. This will be problematic because increasing the cement content is not feasible, and may cause high cost and some other technical problems such as higher heat of hydration and higher drying shrinkage. This paper investigates the effect of limestone powder (LSP) on fresh and hardened properties of SCC due to the use of LSP as a partial cement replacement. For comparison, a control sample of concrete was prepared without LSP to compare it with the various samples containing different percentages of LSP as a partial replacement of cement. Four mixes with a constant amount of (superplasticizer, sand, coarse aggregate, and water) at various replacement levels of 0%, 10%, 20% and 30% from the cement weight were prepared. The experimental results show that the LSP can be effectively used as a partial cement replacement on SCC to reduced cost and enhanced the performance of SCC in fresh and hardened stages.

Download Full-text

Recycling of Coal Ash in Concrete as a Partial Cementitious Resource

Resources ◽

10.3390/resources8020099 ◽

2019 ◽

Vol 8 (2) ◽

pp. 99 ◽

Cited By ~ 5

Author(s):

Sajjad Ali Mangi ◽

Mohd Haziman Wan Ibrahim ◽

Norwati Jamaluddin ◽

Mohd Fadzil Arshad ◽

Sri Wiwoho Mudjanarko

Keyword(s):

Tensile Strength ◽

Bottom Ash ◽

Coal Ash ◽

Pozzolanic Reaction ◽

Concrete Construction ◽

Great Opportunity ◽

Strength Performance ◽

Cement Replacement ◽

Sustainable Concrete ◽

Partial Cement Replacement

Concrete construction offers a great opportunity to replace the cement with a coal-based power plant waste—known as coal bottom ash (CBA)—which offers great environmental and technical benefits. These are significant in sustainable concrete construction. This study aims to recycle CBA in concrete and evaluate its particle fineness influence on workability, compressive and tensile strength of concrete. In this study, a total of 120 specimens were prepared, in which ground CBA with a different fineness was used as a partial cement replacement of 0% to 30% the weight of cement. It was noticed that workability was decreased due to an increased amount of ground CBA, because it absorbed more water in the concrete mix. The growth in the compressive and tensile strength of concrete with ground CBA was not significant at the early ages. At 28 days, a targeted compressive strength of 35 MPa was achieved with the 10% ground CBA. However, it required a longer time to achieve a 44.5 MPa strength of control mix. This shows that the pozzolanic reaction was not initiated up to 28 days. It was experimentally explored that 10% ground CBA—having particle fineness around 65% to 75% and passed through 63 µm sieve—could achieve the adequate compressive and tensile strength of concrete. This study confirmed that the particle fineness of cement replacement materials has a significant influence on strength performance of concrete.

Download Full-text

Development of high-performance self compacting concrete using eggshell powder and blast furnace slag as partial cement replacement

Construction and Building Materials ◽

10.1016/j.conbuildmat.2020.119403 ◽

2020 ◽

Vol 256 ◽

pp. 119403

Author(s):

Olatokunbo M. Ofuyatan ◽

Adewale George Adeniyi ◽

David Ijie ◽

Joshua O. Ighalo ◽

John Oluwafemi

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

High Performance ◽

Self Compacting Concrete ◽

Cement Replacement ◽

Partial Cement Replacement ◽

Furnace Slag

Download Full-text

Characterisation of High Calcium Wood Ash for Use as a Constituent in Wood Ash-Silica Fume Ternary Blended Cement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.346.3 ◽

2011 ◽

Vol 346 ◽

pp. 3-11 ◽

Cited By ~ 4

Author(s):

Cheah Chee Ban ◽

Ramli Mahyuddin

Keyword(s):

Silica Fume ◽

Blended Cement ◽

High Strength ◽

Strength Properties ◽

Wood Ash ◽

Biomass Energy ◽

Cement Replacement ◽

Constituent Material ◽

High Calcium ◽

Partial Cement Replacement

The potential stabilization of high calcium wood waste ash (HCWWA) derived from the wood biomass energy production for use as cementitious material using another industrial by-product, silica fume, was investigated. Throughout the study, both HCWWA and DSF were characterized in term of their respective chemical composition and mineralogical phases. Besides, physical characteristics of HCWWA and DSF in terms of particle grading and specific surface area were established in order to evaluate their suitability as for use as constituent material in blended cement. Additionally, compressive strength properties of high strength mortar produced using HCWWA and DSF blended cement were investigated. Results indicated that the use of HCWWA as a partial cement replacement did not have significant adverse effect on the workability of fresh mortar. The enhancement of the compressive of mortar was observed for mortar mixes containing DSF and HCWWA levels of cement replacement up to 16%.

Download Full-text