**5. Properties of fresh concrete made with used foundry sand**

The properties of fresh concrete made with used foundry sand vary much to that of standard concrete with regular ingredients. The fresh properties of concrete include the workability, temperature, density, and air content.

**15**

**5.2 Temperature**

strength concrete mix is shown in **Figure 5**.

Due to the inclusion of used foundry sand into the concrete mix, the temperature

of the fresh concrete mix changes. Much research results are not available in this regard for the temperature variations. The temperature difference of the concrete

*A Review on the Usage of Recycled Sand in the Construction Industry*

The workability is an essential parameter of the fresh concrete. In most cases, the workability of the concrete made with used foundry sand decreases as the percentage of used foundry sand increases in the mix. As per Khatib et al. [26], the decrease in workability is attributed to the increase in the fineness of the fine aggregate in the mix. However, some researchers reported equal or slightly higher slump values in concrete made with used foundry sand. Mavroulidou and Lawrence [41] stated that the concrete having 20 MPa compressive strength at 28 days made with 100% chemically bonded waste foundry sand showed 160 mm slump as against 120 mm slump for concrete with regular concrete sand. From the research findings on the use of foundry sand in concrete production, Khatib et al. [26] remarked that the slump dropped approximately in a linear manner from 200 mm for the control mix to zero for the mixes containing 80 and 100% waste foundry sand as the replacement of ordinary sand. Manoharan et al. [28] also confirmed that the slump values of concrete having a design compressive strength of 20 MPa at 28 days made with partial replacement of natural river sand with chemically bonded used foundry sand in 0, 5, 10, 15, 20, and 25% showed a significant decrease in slump value when the used foundry sand content increased in the concrete mix. The same trend was also stated by Bhardwaj and Kumar [52] that the addition of waste foundry sand lowered the workability of geopolymer concrete, and the effect was rapid beyond 40% waste foundry sand replacement level. Some researchers noticed that for concrete incorporating used foundry sand, up to a certain percentage replacement of fine aggregates with used foundry sand, the slump value remains constant. After that, the slump value decreases. In the investigation on the effects of foundry sand as a fine aggregate in concrete production, Prabhu et al. [53] observed that up to 10% replacement of fine aggregate with waste foundry sand, the slump value remains constant as that of the control mix, and after that, the slump values decreased. As per Seshadri and Salim [12], the high-performance concrete of 60 MPa characteristic compressive strength prepared with the fractional replacement of manufactured sand with used foundry sand from 0% to 40% showed a decrease in slump values as the percentage of used foundry sand increased in the concrete mix. In this research, the slump obtained was 140 mm for the control highperformance concrete, and at 40% replacement, the slump value obtained was only 105 mm. Ranjitham et al. [35] observed that for 75 MPa characteristic compressive strength high-performance concrete with cement and fly ash, the slump values consistently reduced from 55 to 42 mm with 0–30% addition of foundry sand. From the research on the effect of used-foundry sand on the mechanical properties of concrete, Siddique et al. [54] stated that the concrete having 28.5 MPa characteristic compressive strength showed a decrease in the slump values when the percentage replacement of used foundry sand increased from 0 to 30%. The concrete mix containing used foundry sand normally requires higher dosages of superplasticizers to maintain the workability. The slump variation of the control mix (CM) and the concrete mix with foundry sand (FS) from 10 to 50% replacement of natural sand when tested immediately after mixing, 30 minutes after mixing, and 60 minutes after mixing as reported by Prabhu et al. [15] for 25 MPa characteristic compressive

*DOI: http://dx.doi.org/10.5772/intechopen.92790*

**5.1 Workability**

*A Review on the Usage of Recycled Sand in the Construction Industry DOI: http://dx.doi.org/10.5772/intechopen.92790*

### **5.1 Workability**

*Sandy Materials in Civil Engineering - Usage and Management*

 Guney et al. [21] Highway sub-bases Nabhani et al. [22] Manufacture of asphalt Bakis et al. [23] Asphalt mixtures Javed et al. [24] Asphalt concretes Pasetto and Baldo [25] Road foundation mixtures

15 Basar and Aksoy [34] Ready-mixed concrete

19 Nirmala and Raviraj [37] Self-compacting concrete

21 Hossain and Anwar [39] Lightweight concrete 22 Dogan-Saglamtimur [3] Geopolymer concrete

 Jerusha and Mini [42] Geopolymer concrete Safi et al. [43] Self-compacting mortars Cevik et al. [44] Cement mortars Navarro-Blasco et al. [45] Cement mortars Marchioni et al. [46] Paver blocks

30 Santos et al. [47] Paver blocks 31 Tausif et al. [46] Paver blocks 32 Kulkarni and Katti [49] Concrete pavers

20 Makul [38] High-performance self-consolidating concrete

23 Bhardwaj and Kumar [40] Ambient cured geopolymer concrete

29 Kewal et al. [13] Paver blocks with geopolymer concrete

33 Mahima et al. [50] High-strength solid masonry blocks

**Sl. No. Researchers Application of used foundry sand** Yazoghli-Marzouk et al. [18] Sub-base layer in road construction Iqbal et al. [19] Material for embankment and structural fill Arulrajah et al. [20] Road embankment fill and pipe bedding

9 Manoharan et al. [28] Concrete of compressive strength of 20 MPa 10 Sohail et al. [30] Concrete of compressive strength of 30 MPa 11 Singh and Siddique [31] Concrete of compressive strength of 40 MPa

 Guney et al. [14] High-strength concrete of compressive strength of 65 MPa Chandrasekar et al. [32] High-strength concrete of compressive strength of 60 MPa Torres et al. [33] Ultra-high-strength concrete of compressive strength of 120 MPa

16 Seshadri and Salim [12] High-performance concrete of design compressive strength of 60 MPa 17 Ranjitham et al. [35] High-performance concrete of design compressive strength of 75 MPa 18 Siddique and Sandhu [36] Self-compacting concrete having a compressive strength of 30 MPa

**5. Properties of fresh concrete made with used foundry sand**

include the workability, temperature, density, and air content.

The properties of fresh concrete made with used foundry sand vary much to that of standard concrete with regular ingredients. The fresh properties of concrete

34 Naik et al. [51] Concrete products like bricks, blocks, and paving stones

**14**

**Table 1.**

*Summary of research studies.*

The workability is an essential parameter of the fresh concrete. In most cases, the workability of the concrete made with used foundry sand decreases as the percentage of used foundry sand increases in the mix. As per Khatib et al. [26], the decrease in workability is attributed to the increase in the fineness of the fine aggregate in the mix. However, some researchers reported equal or slightly higher slump values in concrete made with used foundry sand. Mavroulidou and Lawrence [41] stated that the concrete having 20 MPa compressive strength at 28 days made with 100% chemically bonded waste foundry sand showed 160 mm slump as against 120 mm slump for concrete with regular concrete sand. From the research findings on the use of foundry sand in concrete production, Khatib et al. [26] remarked that the slump dropped approximately in a linear manner from 200 mm for the control mix to zero for the mixes containing 80 and 100% waste foundry sand as the replacement of ordinary sand. Manoharan et al. [28] also confirmed that the slump values of concrete having a design compressive strength of 20 MPa at 28 days made with partial replacement of natural river sand with chemically bonded used foundry sand in 0, 5, 10, 15, 20, and 25% showed a significant decrease in slump value when the used foundry sand content increased in the concrete mix. The same trend was also stated by Bhardwaj and Kumar [52] that the addition of waste foundry sand lowered the workability of geopolymer concrete, and the effect was rapid beyond 40% waste foundry sand replacement level. Some researchers noticed that for concrete incorporating used foundry sand, up to a certain percentage replacement of fine aggregates with used foundry sand, the slump value remains constant. After that, the slump value decreases. In the investigation on the effects of foundry sand as a fine aggregate in concrete production, Prabhu et al. [53] observed that up to 10% replacement of fine aggregate with waste foundry sand, the slump value remains constant as that of the control mix, and after that, the slump values decreased. As per Seshadri and Salim [12], the high-performance concrete of 60 MPa characteristic compressive strength prepared with the fractional replacement of manufactured sand with used foundry sand from 0% to 40% showed a decrease in slump values as the percentage of used foundry sand increased in the concrete mix. In this research, the slump obtained was 140 mm for the control highperformance concrete, and at 40% replacement, the slump value obtained was only 105 mm. Ranjitham et al. [35] observed that for 75 MPa characteristic compressive strength high-performance concrete with cement and fly ash, the slump values consistently reduced from 55 to 42 mm with 0–30% addition of foundry sand. From the research on the effect of used-foundry sand on the mechanical properties of concrete, Siddique et al. [54] stated that the concrete having 28.5 MPa characteristic compressive strength showed a decrease in the slump values when the percentage replacement of used foundry sand increased from 0 to 30%. The concrete mix containing used foundry sand normally requires higher dosages of superplasticizers to maintain the workability. The slump variation of the control mix (CM) and the concrete mix with foundry sand (FS) from 10 to 50% replacement of natural sand when tested immediately after mixing, 30 minutes after mixing, and 60 minutes after mixing as reported by Prabhu et al. [15] for 25 MPa characteristic compressive strength concrete mix is shown in **Figure 5**.

#### **5.2 Temperature**

Due to the inclusion of used foundry sand into the concrete mix, the temperature of the fresh concrete mix changes. Much research results are not available in this regard for the temperature variations. The temperature difference of the concrete

**Figure 5.** *Workability variation of foundry sand concrete.*

mix is attributable to the chemical action of the chemicals present in the used foundry sand with cement and water. In the research report on the application of used foundry sand in concrete production, Prabhu et al. [53] stated that for 20 and 30% replacement of fine aggregate with used foundry sand, the concrete showed an increase in temperature of 1°C from the room temperature. Some researchers observed no variations in fresh concrete temperature to that of room temperature by the addition of used foundry sand in the concrete mix. Manoharan et al. [28] reported that the concrete made with natural river sand replaced with used foundry sand from 10 to 25% in 5% increments had no difference between the room temperature and the fresh concrete temperature. Naik et al. [55] stated that the fresh concrete containing 25 and 35% used foundry sand showed the same temperature as that of room temperature, whereas the control mix showed a 2°C less temperature as that of room temperature. Seshadri and Salim [12] stated that for high-performance concrete made with partial replacement of fine aggregates with used foundry sand, the temperature of the fresh concrete was less than that of the room temperature for all the replacement from 0 to 40%, and the highest temperature difference observed for the replacement of 30 and 35% has a value of 3.5°C, whereas for the control mix, the value observed was 2.5°C.

#### **5.3 Density**

The specific gravity of the used foundry sand is normally less than the specific gravity of the fine aggregates. Hence, the density of the concrete incorporating used foundry sand may vary depending on the percentage of the used foundry sand in the concrete mix. Few researchers only reported the density of fresh concrete incorporating used foundry sand. Manoharan et al. [28] stated that the fresh density of concrete made with partial replacement of natural river sand with chemically bonded used foundry sand showed a marginal decrease in fresh density when the used foundry sand content increased from 0 to 25% in the concrete mix, the control mix has a fresh density of 2373 kg/m3 , whereas the concrete containing 25% used foundry sand has a fresh density of 2355 kg/m3 only.

In some cases, the addition of used foundry sand does not affect the fresh density of concrete. Siddique et al. [54] investigated the effect of used-foundry sand on the mechanical properties of concrete. They reported that the concrete made

**17**

*A Review on the Usage of Recycled Sand in the Construction Industry*

and 30% used foundry sand has a fresh density of 2332 kg/m3

the percentage of foundry sand in the mix from 2522 to 2502 kg/m3

sand and remains constant further up to 35% replacement.

are discussed in detail in the following paragraphs.

**6.1 Compressive strength**

**6. Properties of hardened concrete made with used foundry sand**

Many researchers reported the hardened properties of concrete made with used foundry sand at different curing periods. The mechanical properties include compressive strength, split tensile strength, flexural strength, and modulus of elasticity. The mechanical properties of hardened concrete made using waste foundry sand

The concrete incorporating used foundry sand generally shows higher compressive strength than the normal concrete. In some cases, the compressive strength of concrete made with partial replacement of fine aggregates with used foundry sand was below or equal to that of the control mix. Siddique et al. [54] reported that the concrete having the 28th-day compressive strength of 28.5 MPa made with 0, 10, 20, and 30% replacement of sand with used foundry sand, the compressive strength was consecutively increased from 28.5 to 31.3 MPa. Manoharan et al. [28] reported the 28th-day compressive strength of concrete with 0 and 20% chemically bonded

with used foundry sand showed almost the same fresh density as that of the control mix for 10–30% replacement of fine aggregates with used foundry sand in which

observed similar trends and confirmed that the control mix and concrete with 35% used foundry sand have the same fresh density, and fresh density of concrete with 25% used foundry sand has shown an increase in 1.30% over the control mix. For the ultra-high-strength concrete made with used foundry sand, also the fresh density has variation over the control mix. Torres et al. [33] investigated the properties of ultra-high-strength concrete made with silica fume, river sand, steel fibers, and green sand at 0, 10, 20, and 30% by weight of cement. They observed that the fresh density of ultra-high-strength concrete marginally decreased with the increase in

A small quantity of air is entrapped in the concrete. Depending on the concrete mix and type of compaction, the entrapped air content may vary. Manoharan et al. [28] investigated the properties of chemically bonded used foundry sand incorporated concrete and reported that the air content of fresh concrete made with partial replacement of natural river sand with used foundry sand showed a marginal increase with an increase in the used foundry sand content in the concrete mix, the control mix has an air content of 5.2%, whereas the concrete with 25% used foundry sand has an air content of 5.7%. Siddique et al. [54] also observed similar trends in air content for the concrete made with used foundry sand and stated that the air content of the concrete with used foundry sand has a higher percentage of air content than the control mix in which the control mix has an air content of 4.2%, whereas the air content at 10% used foundry sand, the air content value was increased to 4.5%. In some cases, the air content of the concrete mix made with used foundry sand is found to be less than the air content of the regular mix. Naik et al. [55] observed that the air content of the concrete made with used foundry sand tends to decrease up to 25% replacement of fine aggregate with used foundry

, and the concrete with 10, 20,

.

. Naik et al. [55] also

*DOI: http://dx.doi.org/10.5772/intechopen.92790*

**5.4 Air content**

the control mix has a fresh density of 2331 kg/m3

*A Review on the Usage of Recycled Sand in the Construction Industry DOI: http://dx.doi.org/10.5772/intechopen.92790*

with used foundry sand showed almost the same fresh density as that of the control mix for 10–30% replacement of fine aggregates with used foundry sand in which the control mix has a fresh density of 2331 kg/m3 , and the concrete with 10, 20, and 30% used foundry sand has a fresh density of 2332 kg/m3 . Naik et al. [55] also observed similar trends and confirmed that the control mix and concrete with 35% used foundry sand have the same fresh density, and fresh density of concrete with 25% used foundry sand has shown an increase in 1.30% over the control mix. For the ultra-high-strength concrete made with used foundry sand, also the fresh density has variation over the control mix. Torres et al. [33] investigated the properties of ultra-high-strength concrete made with silica fume, river sand, steel fibers, and green sand at 0, 10, 20, and 30% by weight of cement. They observed that the fresh density of ultra-high-strength concrete marginally decreased with the increase in the percentage of foundry sand in the mix from 2522 to 2502 kg/m3 .

## **5.4 Air content**

*Sandy Materials in Civil Engineering - Usage and Management*

mix is attributable to the chemical action of the chemicals present in the used foundry sand with cement and water. In the research report on the application of used foundry sand in concrete production, Prabhu et al. [53] stated that for 20 and 30% replacement of fine aggregate with used foundry sand, the concrete showed an increase in temperature of 1°C from the room temperature. Some researchers observed no variations in fresh concrete temperature to that of room temperature by the addition of used foundry sand in the concrete mix. Manoharan et al. [28] reported that the concrete made with natural river sand replaced with used foundry sand from 10 to 25% in 5% increments had no difference between the room temperature and the fresh concrete temperature. Naik et al. [55] stated that the fresh concrete containing 25 and 35% used foundry sand showed the same temperature as that of room temperature, whereas the control mix showed a 2°C less temperature as that of room temperature. Seshadri and Salim [12] stated that for high-performance concrete made with partial replacement of fine aggregates with used foundry sand, the temperature of the fresh concrete was less than that of the room temperature for all the replacement from 0 to 40%, and the highest temperature difference observed for the replacement of 30 and 35% has a value of 3.5°C, whereas for the control mix, the value observed was 2.5°C.

The specific gravity of the used foundry sand is normally less than the specific gravity of the fine aggregates. Hence, the density of the concrete incorporating used foundry sand may vary depending on the percentage of the used foundry sand in the concrete mix. Few researchers only reported the density of fresh concrete incorporating used foundry sand. Manoharan et al. [28] stated that the fresh density of concrete made with partial replacement of natural river sand with chemically bonded used foundry sand showed a marginal decrease in fresh density when the used foundry sand content increased from 0 to 25% in the concrete mix, the control

In some cases, the addition of used foundry sand does not affect the fresh density of concrete. Siddique et al. [54] investigated the effect of used-foundry sand on the mechanical properties of concrete. They reported that the concrete made

, whereas the concrete containing 25% used

only.

**16**

**5.3 Density**

**Figure 5.**

*Workability variation of foundry sand concrete.*

mix has a fresh density of 2373 kg/m3

foundry sand has a fresh density of 2355 kg/m3

A small quantity of air is entrapped in the concrete. Depending on the concrete mix and type of compaction, the entrapped air content may vary. Manoharan et al. [28] investigated the properties of chemically bonded used foundry sand incorporated concrete and reported that the air content of fresh concrete made with partial replacement of natural river sand with used foundry sand showed a marginal increase with an increase in the used foundry sand content in the concrete mix, the control mix has an air content of 5.2%, whereas the concrete with 25% used foundry sand has an air content of 5.7%. Siddique et al. [54] also observed similar trends in air content for the concrete made with used foundry sand and stated that the air content of the concrete with used foundry sand has a higher percentage of air content than the control mix in which the control mix has an air content of 4.2%, whereas the air content at 10% used foundry sand, the air content value was increased to 4.5%. In some cases, the air content of the concrete mix made with used foundry sand is found to be less than the air content of the regular mix. Naik et al. [55] observed that the air content of the concrete made with used foundry sand tends to decrease up to 25% replacement of fine aggregate with used foundry sand and remains constant further up to 35% replacement.
