Enhancing the Compressive Strength of Concrete Hollow Blocks Using Ash of Sugarcane (Saccharum officinarum) Bagasse and Coconut (Cocos nucifera) Husk

Abstract

INTRODUCTION

Rapid crack propagation, brittle mode of failure, and increased overload are common in concrete structures due to the low tensile strength of concrete hollow blocks. Although conventional steel reinforced concrete is the most popular method to reduce such problems, it is rather becoming expensive. This has led to a lot of challenges such as building collapse usually accompanied by devastating economic and human loss. for these drawbacks, the development of contemporary concrete technologies such as eco-friendly and affordable concrete mixtures for hollow blocks can be helpful. The selection of building materials should meet the needs of local conditions by building new structures and/or by improving existing structures. The researchers decided to combine the ash of fibrous materials, i.e., coconut husk and sugarcane bagasse. Coconut fiber is a natural fiber extracted from the coconut husk, found in between the internal shell and the outer coat of the coconut. Bagasse is the dry pulpy fibrous residue when sugarcanes are crushed for juice extraction. According to Kumator Taku (2012) the ash helps improve the compressive strength of concrete hollow blocks. The researchers decided to mix different amounts of ash of coconut husk and sugarcane bagasse to see if the fiber-reinforced concrete mixture is stronger than the commercial ones in terms of compressive strength.

METHODS

Sugarcane bagasse and coconut husks were collected and dried for 7 days. These were then burned inside a drum, then cooled. After the ashes cool, these were sieved. 15kgs cement was mixed with 4L of water and 60kgs of sand. The whole batch was then divided into 9. The first part was mixed with 250g of CHA and 750g SCBA, the second one was mixed with 500g CHA and 500g SCBA, and the last part was mixed with 750g CHA and 250g SCBA. The hollow blocks were tested for compressive strength.

RESULTS

The results of the compressive strength of hollow blocks with CHA and SCBA are shown. The first trial with 250g CHA and 750g SCBA showed a weighted mean of 162.33. While the second trial with 500g CHA mix with 500g SCBA showed a weighted mean of 253.67. The last trial with 750g CHA mix with 250g SCBA showed a weighted mean of 224.67.

DISCUSSIONS

The results prove that hollow blocks with 500g SCBA and 500g CHA is greater by 185 units than the commercial concrete hollow blocks, the latter only having 68.67 units of compressive strength.