The effect of waste foundry sand (WFS) as partial replacement of sand on the mechanical, leaching and micro-structural characteristics of ready-mixed concrete
Highlights
► Potential re-use of waste foundry sand (WFS) in ready-mixed concrete (RMC). ► Utilization of WFS as partial replacement of fine aggregate (regular sand). ► Regular sand has been replaced by WFS (0%, 10%, 20%, 20%, 40%). ► Effects of WFS on the mechanical, leaching and micro-structural properties of RMC. ► WFS can be effectively used in making good quality RMC with no adverse impacts.
Introduction
The usage of ready-mixed concrete (RMC) together with modern construction technologies is one of the requirements of modern life, healthy urbanization and safe structuring. The RMC sector is a subdivision of construction industry being at a crucial position in Turkey and it is relatively new compared to other countries. Germany is the first country where RMC industry emerged in the year of 1903; however, the first RMC was produced in 1976 in Turkey [1]. According to the European Ready Mixed Concrete Organization (ERMCO), 79.7 million metric tons of RMC were produced in Turkey in the year 2010 corresponding to the 21% of the total production of RMC in Europe [2].
RMC is a type of concrete that is specifically manufactured for delivery to the customer’s construction site in a freshly mixed and plastic or unhardened state [3]. The crucial difference between RMC and conventional concrete is the production of RMC in modern facilities following scientific methods in accordance with standards. RMC is composed of 75% aggregate, 10% cement and 15% water by weight.
The RMC industry consumes high amounts of aggregates, i.e., sand, gravel and crushed rock. It is estimated that the aggregate demand for only RMC production is 140 million tons per year in Turkey and will increase sharply in the upcoming years. In order to maintain the current supply from existing natural resources at constant level, alternative sources such as blast-furnace slag, fly ash and foundry sand can be used for aggregates.
Foundry sand is a high-quality silica sand that is by-product of metal casting industries, where it has been utilized for many years as a mold mainly due to its thermal conductivity [4]. Ferrous and non-ferrous foundries use silica sand in order to create metal casting molds and cores. During the casting process, molds can be exposed to high temperatures (∼1500 °C) depending upon the metal being poured [5]. The molding sands can be reused for several times (about 8–10 times) until losing its molding characteristics before the repeated exposure to molten metal and mechanical abrasion [6], [7]. Finally, when the recycled sand degrades to the point at which it can no longer be reused in the metal casting process [7], it is removed from the foundry and named as “waste foundry sand” (WFS) [8].
Section snippets
Literature review
As WFS is basically a fine aggregate, it is reasonable to anticipate that it can be used in many applications where natural sands are used [9]. Several researchers have investigated the use of WFS in various civil engineering applications, manufactured products and geotechnical applications, some of whose work has been listed in the following: the use of WFS in highway applications [10], [11], [12], [13], [14]; concrete and concrete related products (i.e., bricks, blocks and paving stones) [4],
Cement
Ordinary Portland cement (CEM I 42.5R) conforming to Turkish standard specifications TS EN 197-1:2002 was used in all concretes.
Waste foundry sand
WFS used in this study is green sand obtained locally from ferrous foundry located in the Marmara Region of Turkey which produces metal components for the automotive industry. WFS was used as partial replacement of fine aggregate (regular sand). Therefore, analysis for the determination of the geometrical, physical and chemical properties of WFS and regular sand are
Compressive strength and modulus of elasticity
Compressive strength of concrete specimens prepared with and without WFS was determined at the ages of 7, 28, 56 and 90 days. The results are shown in Fig. 1. It is observed that compressive strength of conventional concrete was 43.2 MPa at 28-day, which is the highest one. Furthermore, concrete mixtures containing WFS exhibited lower compressive strength than conventional concrete at all ages. The results also showed that compressive strength of all concrete mixtures increased with age. Similar
Conclusions
The following conclusions are drawn from this investigation:
- 1.
WFS exhibited almost similar geometrical, physical and chemical properties as that of regular sand (fine aggregate) according to the Turkish Standard “TS 706 EN 12620+A1:2009-Concrete aggregates”.
- 2.
Partial replacement of regular sand with WFS decreases the strength performance (compressive strength, tensile splitting strength and modulus of elasticity) of concrete at all ages.
- 3.
The strength properties of all concrete mixtures increases
Acknowledgements
The authors wish to thank TÜBİTAK Marmara Research Center, İSTON A.Ş. and Turkish Ready Mixed Concrete Association for their support in this research.
References (37)
- et al.
Effect of used-foundry sand on the mechanical properties of concrete
Construct Build Mater
(2009) - et al.
Concentrations of PCDD/PCDFs and PCBs in spent foundry sands
Chemosphere
(2009) - et al.
Re-usage of waste foundry sand in high-strength concrete
Waste Manage (Oxford)
(2010) - et al.
Utilization of spent foundry sand in controlled low-strength materials and concrete
Resour Conserv Recycl
(2008) - et al.
Strength, durability and micro-structural properties of concrete made with used-foundry sand (UFS)
Construct Build Mater
(2011) - et al.
Properties of concrete using metallurgical industrial by-products as aggregates
Construct Build Mater
(2010) - et al.
Geotechnical and leaching properties of flowable fill incorporating waste foundry sand
Waste Manage (Oxford)
(2008) - et al.
Waste foundry sand and its leachate characteristics
Resour Conserv Recycl
(2010) - et al.
By-products and recycled materials in earth construction in Finland – an assessment of applicability
Resour Conserv Recycl
(2002) - Karakule F, Akakın T, Ucar S. Ready-mixed concrete industry in Turkey and in the world. In: Proceedings of concrete...
Characterization of physical and chemical properties of spent foundry sands pertinent to beneficial use in manufactured soils
Plant Soil
Evaluation of foundry wastes for use in highway construction
ASCE Environ Eng
Geotechnical performance of a highway embankment constructed using waste foundry sand
Geotechn Spec Publ
Using waste foundry sand for hydraulic barriers
ASCE Geotechn Spec Publ
Cited by (145)
Red mud as a sustainable road construction material: An experimental investigation
2024, Construction and Building MaterialsForecasting the strength characteristics of concrete incorporating waste foundry sand using advance machine algorithms including deep learning
2023, Case Studies in Construction MaterialsFeasibility of waste foundry sand in high-strength self-compacting concrete and the effects of elevated temperatures
2023, Construction and Building MaterialsA novel hybrid adaptive boosting approach for evaluating properties of sustainable materials: A case of concrete containing waste foundry sand
2023, Journal of Building EngineeringMachine learning approach for predicting concrete compressive, splitting tensile, and flexural strength with waste foundry sand
2023, Journal of Building Engineering