Optimum Oil Palm Shell Content as Coarse Aggregate in Concrete Based on Mechanical and Durability Properties

Mehdi Maghfouri,Muhammad Aslam,Payam Shafigh

doi:10.1155/2018/4271497

Abstract

Oil palm shell (OPS) is a biosolid waste in palm oil industry in the tropical countries which could be used as aggregate in concrete mixture. Since 1984, OPS has been experimented as natural lightweight aggregate in research studies to produce lightweight concrete (LWC). Medium and high-strength LWCs using OPS as coarse aggregate were successfully produced. However, higher drying shrinkage and lower mechanical properties for concretes containing higher volume of OPS are reported in previous studies. Therefore, OPS is not fit to be used as full coarse aggregate in concrete mixture and therefore, there should be an optimum OPS content in concrete. In this study, in a normal-weight concrete, normal coarse aggregate was replaced with OPS from zero to 100% with an interval of 20%. Tests such as slump, density, compressive strength in different curing conditions, splitting tensile strength, initial and final water absorptions, and drying shrinkage of cured and uncured specimens were conducted to find out optimum OPS content in concrete. From the test results, it could be summarized that OPS content should not exceed 60% of total volume of coarse aggregate.

Highlights

Growing of the human population and consumption of the natural resources lead to production of large quantities of the waste which causes environmental issues
In order to achieve the optimum level of oil palm shell (OPS) contribution in concrete mixture for production of the lightweight aggregate concrete, six concrete mixes with different level of OPS as replacement of crushed granite from 20 to 100% with interval of 20% were produced. e obtained results of the mechanical properties and drying shrinkage are represented as follows: (1) Replacement level of OPS from 60 to 100% in normal-weight concrete transformed it into lightweight concrete, whereas concrete mixes containing 20 to 60% of OPS aggregate, with oven-dry density between 2100 and 2200 kg/m3 are categorized as semi-lightweight aggregate concretes
(2) In improper curing condition, concrete containing OPS aggregates has higher loss of compressive strength compared to conventional aggregate concrete

Summary

Introduction

Growing of the human population and consumption of the natural resources lead to production of large quantities of the waste which causes environmental issues. OPS lightweight concrete grades 30 and 35 MPa were successfully produced by using fly ash at 50% and 30% replacement levels of the cement content It has a lower compressive strength than the reference ordinary concrete [18]. Because of the importance of OPS content in concrete, in order to achieve satisfactory mechanical properties and less drying shrinkage, this investigation was carried out to find out the optimum substitution of oil palm shell in conventional concrete to produce durable structural lightweight aggregate concrete. E results of the present study can be effectively used as a reference for production of structural OPS lightweight concrete in precast and construction industry since there is an optimum level of OPS to meet requirements of both mechanical properties and drying shrinkage

Materials

Results and Discussion

Conclusion