Assessment on engineering properties and CO2 emissions of recycled aggregate concrete incorporating waste products as supplements to Portland cement

This paper presents an experimental investigation on the durability properties and carbon dioxide (CO2) emissions of concrete developed using waste products. The concrete comprised of recycled concrete aggregate (RA) as a complete coarse aggregate replacement. In addition, rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) were used as replacement materials for cement at levels up to 30%. The supplementary cementitious materials (SCMs) were used in RA concrete with the aim of reducing the dependency on cement as a stand-alone binder. The compressive strength, water absorption, chloride-ion penetration and electrical resistivity were investigated for RA concrete containing SCMs. Moreover, the residual compressive strength was also examined along with the weight loss to check the elevated temperature resistance of RA concrete with SCMs. The results revealed that

Effect of Coating Palm Oil Clinker Aggregate on the Engineering Properties of Normal Grade Concrete

Palm oil clinker (POC) is a waste material generated in large quantities from the palm oil industry. POC, when crushed, possesses the potential to serve as an aggregate for concrete production. Experimental investigation on the engineering properties of concrete incorporating POC as aggregate and filler material was carried out in this study. POC was partially and fully used to replace natural coarse aggregate. The volumetric replacements used were 0%, 20%, 40%, 60%, 80%, and 100%. POC, being highly porous, negatively affected the fresh and hardened concrete properties. Therefore, the particle-packing (PP) method was adopted to measure the surface and inner voids of POC coarse aggregate in the mixtures at different substitution levels. In order to enhance the engineering properties of the POC concrete, palm oil clinker powder (POCP) was used as a filler material to fill up and coat the surface voids of POC coarse, while the rest of the mix constituents were left as the same. Fresh and hardened properties of the POC concrete with and without coating were determined, and the results were compared with the control concrete. The results revealed that coating the surface voids of POC coarse with POCP significantly improved the engineering properties as well as the durability performance of the POC concrete. Furthermore, using POC as an aggregate and filler material may reduce the continuous exploitation of aggregates from primary sources. Also, this approach offers an environmental friendly solution to the ongoing waste problems associated with palm oil waste material

Engineering properties of normal and high strength concrete containing palm oil clinker / Fuad Y. M. Abutaha

Utilization of locally available waste materials to replace conventional concrete materials has gained considerable attention in the past two decades. Palm oil clinker (POC) is a lightweight waste material generated from the palm oil industry in Malaysia. POC, when crushed possesses the potential as aggregates for concrete production. Experimental investigation on the usage of POC as a partial and full replacement of the natural aggregates and filler material was carried out in this study. Normal and high strength concrete of 40 and 90 MPa respectively, were the design strength for the purpose of this study. Department of environment (DOE) and Sherbrooke mix design methods were adopted to produce the normal and high strength concrete, respectively. Crushed POC was partially and fully used to replace natural aggregates i.e. fine and coarse. The percentage of POC replacement used are 0%, 20%, 40%, 60%, 80% and 100% of the total volume of fine and coarse aggregate, separately. Particle-packing (PP) method was then adopted for the mixes where coarse aggregate was substituted with POC. To enhance the engineering properties of POC concrete, addition of Palm oil clinker powder (POCP) was then incorporated to the mixes as a filler material to fill up the voids of POC, while maintaining the other mix constituents. Fresh and hardened properties were investigated for the concrete mixes with and without POCP and the results were compared to the control concrete, which was prepared using natural aggregates. POC, being highly porous had a negative effect on the fresh and hardened concrete properties when coarse aggregate was substituted with POC. Meanwhile, the replacement of the natural sand with POC fine had insignificant effect on fresh and hardened properties of concrete. The results also revealed that incorporating additional POCP to normal and high strength POC concrete improved the engineering properties as well as the durability performance. Therefore, there is a great potential towards utilization of POC in the normal concrete production. This approach offers an environmental friendly solution to the ongoing challenge of palm oil mill waste materials

Effect of Coating Palm Oil Clinker Aggregate on the Engineering Properties of Normal Grade Concrete

Palm oil clinker (POC) is a waste material generated in large quantities from the palm oil industry. POC, when crushed, possesses the potential to serve as an aggregate for concrete production. Experimental investigation on the engineering properties of concrete incorporating POC as aggregate and filler material was carried out in this study. POC was partially and fully used to replace natural coarse aggregate. The volumetric replacements used were 0%, 20%, 40%, 60%, 80%, and 100%. POC, being highly porous, negatively affected the fresh and hardened concrete properties. Therefore, the particle-packing (PP) method was adopted to measure the surface and inner voids of POC coarse aggregate in the mixtures at different substitution levels. In order to enhance the engineering properties of the POC concrete, palm oil clinker powder (POCP) was used as a filler material to fill up and coat the surface voids of POC coarse, while the rest of the mix constituents were left as the same. Fresh and hardened properties of the POC concrete with and without coating were determined, and the results were compared with the control concrete. The results revealed that coating the surface voids of POC coarse with POCP significantly improved the engineering properties as well as the durability performance of the POC concrete. Furthermore, using POC as an aggregate and filler material may reduce the continuous exploitation of aggregates from primary sources. Also, this approach offers an environmental friendly solution to the ongoing waste problems associated with palm oil waste material

Adopting particle-packing method to develop high strength palm oil clinker concrete

Utilization of locally available waste and by-product to replace conventional concrete materials has gained considerable attention over the past two decades. This study is a part of an extensive research program on the characteristics of palm oil clinker (POC) incorporated concrete. In this study, experimental investigation was carried out on incorporating POC as aggregates and filler material in the production of high strength concrete (HSC). Crushed POC were used as partial and full replacement of natural aggregates i.e. fine and coarse. Palm oil clinker powder (POCP) was then incorporated to fill the voids present on the surface of POC particles, while maintaining the other mix constituents. Fresh and hardened properties of the POC concrete with and without POCP were investigated. Substituting coarse aggregate with POC negatively affected the concrete fresh and hardened properties due to POC porous nature. However, the results of the study revealed that incorporating additional POCP as filler material by adopting Particle-Packing (PP) method improved the engineering properties of POC concrete. Therefore, there is a potential towards utilization of POC for many practical construction applications. POC being an environmentally-friendly and a low-cost aggregate can serve as a normal aggregate alternative for future use

Viability of agricultural wastes as substitute of natural aggregate in concrete: A review on the durability-related properties

Increase in construction activities has led to rapid depletion of natural resources, particularly aggregates which are utilized in the production of concrete. At the same time, there are huge amount of solid wastes originating from the agricultural industry, particularly from the South East Asia region, such as oil palm shell (OPS), oil palm boiler clinker (OPBC) and coconut shell. Research have since been undertaken to investigate the feasibility of these waste materials as potential substitute for conventional aggregate in concrete. Durability of concretes, especially those containing recycled waste materials are often subjected to scrutiny. Therefore, this paper reviews the published findings on the durability-related properties of concrete containing these agricultural waste materials as aggregate. Due to improved binder quality (lower w/b ratio and higher binder content), concrete prepared with these wastes generally exhibit acceptable quality in terms of water absorption, sorptivity and chloride penetrability. The major drawbacks are associated with the higher drying shrinkage, susceptibility towards severe chemical attack and elevated temperature. Among these wastes, OPBC aggregate is considered to have the best performance based on the reviewed properties, while OPS aggregate and coconut shell aggregate are recommended to be used only as partial aggregate replacement. Current available studies, however, are still insufficient and more in-depth investigations are required to ascertain the suitability of these wastes to be re-used as aggregate replacement in concrete.No sponso

Assessment on engineering properties and CO2 emissions of recycled aggregate concrete incorporating waste products as supplements to Portland cement

This paper presents an experimental investigation on the durability properties and carbon dioxide (CO 2 ) emissions of concrete developed using waste products. The concrete comprised of recycled concrete aggregate (RA) as a complete coarse aggregate replacement. In addition, rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) were used as replacement materials for cement at levels up to 30%. The supplementary cementitious materials (SCMs) were used in RA concrete with the aim of reducing the dependency on cement as a stand-alone binder. The compressive strength, water absorption, chloride-ion penetration and electrical resistivity were investigated for RA concrete containing SCMs. Moreover, the residual compressive strength was also examined along with the weight loss to check the elevated temperature resistance of RA concrete with SCMs. The results revealed that the use of 30% RHA as SCM produced the highest compressive strength efficiency of 0.143 MPa/kg cement among all mixes at the age of 90 days. In addition, a significant enhancement was observed for the durability-related properties at later ages, although the engineering properties of RA concrete containing SCMs was low at the age of 28 days. The thermogravimetric (TG) analysis indicated that the RHA is more effective as a pozzolanic additive than POFA and POCP. The CO 2 emissions from RA concrete were reduced by approximately 29% when it was incorporated with 30% SCM, where the eco-strength efficiency showed the highest values at 20% cement replacement level of 20%

Performance of mechanical steel bar splices using grouted couplers under uniaxial tension

In this study, grouted couplers were used to connect steel bars as an alternative approach to the conventional steel bar lapping method. The aim is to avoid bar congestion problems and to reduce the required quantity of steel bars in order to achieve the development length in practice. Two categories of couplers, i.e., short-threaded grout coupler and long grout coupler, in nine groups as well as one group of deformed bars, were tested under uniaxial tension. In total, 30 samples (including three repeated samples in each group) were tested. The examined parameters were types of couplers, embedded bar length, and bar eccentricity. For the short-threaded grout couplers, the embedded bar length, which is equivalent to 8 times bar diameter with bar eccentricity equal to zero, exhibited the best performance in terms of strength, ductility, energy absorption, and failure mode, which is suitable to be used in the high seismic zone. Additionally, the short-threaded grout couplers with the embedded bar length equal to 7 times bar diameter and the long grout couplers that required embedded bar length that is equal to 8 times bar diameter, are suitable to be used in the low-to-medium seismic zone. Besides, the embedded bar length that is smaller than or equal to the 6 times bar diameter was not sufficient to be utilised in the short-threaded grout couplers and long grout couplers to resist the seismic load due to inadequate bar embedded length. Also, the predicted model is sufficient to estimate the ultimate tensile strength of the grouted couplers.No sponso

Hydraulic and strength characteristics of pervious concrete containing a high volume of construction and demolition waste as aggregates

Recently, construction and demolition waste generated in Malaysia has dramatically increased. For long-term sustainable development, demolition wastes can be recycled in concrete production. Recycled concrete aggregate (RCA) was successfully used in our previous study as coarse aggregate replacement. This research aims to explore the production of a greener RCA-based pervious concrete by using recycled fine aggregates (RFA). The percentage of waste in the concrete will be 72% by volume of the total concrete mixture constituents. The mixture design is based on a targeted porosity of 15% at the water to cement (w/c) ratios of 0.30, 0.35, and 0.40. Furthermore, the effects of 10% (weight of coarse aggregate) river sand and RFA on the mechanical properties and hydraulic conductivity were compared. The experimental results revealed that 0.35 w/c produced the best mechanical properties. However, the w/c ratio had no effect on the hydraulic properties of the concrete. In addition, incorporating RFA into the concrete improved its mechanical properties, where the compressive and splitting tensile strength of the concrete improved by 7% and 37% respectively. Comparing between RFA and river sand, microscopic analyses showed that the adhered mortar on RFA reduced its crack diversion ability in enhancing the pervious concrete’s strength.No sponso