The assessment of cement partially replaced with calcium carbide waste pow-der, CCWP and bamboo leaf ash, BLA on the strength of concrete made with cement was investigated. Oxide composition analysis of CCWP and BLA con-firm their status as non-pozzolanic material rich in CaO component and poz-zolanic materials, respectively. Setting times, slump, compressive and micro-structure analysis tests were c onducted on fresh and hardened concrete. Twen-ty-eight (28) and fifty-six (56) days peak compressive strength values of 13.23 N/mm2 and 15.97 N/mm2 respectively were obtained when 5% CCWP was mixed with 5% BLA plus 90% cement. Values comparable to 28 and 56 days peak compressive strength values of 13.03 N/mm2 and 15.07 N/mm2 respec-tively obtained when cement was only used as a binder. The use of CCWP and BLA in concrete will ensure economy in concrete production and a better way of disposing these wastes.
The possibility of incorporating wastes from industrial or agricultural processes in the construction industry is borne out of the need to provide sustainable materials for construction. This is achieved either by searching for or incorporating new materials and products that are more environmental friendly and/or contributing towards the reduction of carbon dioxide emission into the atmosphere [
Research trends in materials development have also focused on providing alternatives necessitated by the high cost of conventional materials, and challenges in accessing fund for construction/building development, amongst many other reasons. The alternatives to conventional materials include use of pozzolanas as substitutes to cement or as mineral admixtures and use of other binders from agricultural wastes and by-products from industrial processes as admixtures or additives. In many developing countries the demand for building construction materials such as Ordinary Portland cement and admixtures is high to meet the infrastructure needs of the citizens [
Agricultural and industrial byproducts regarded as wastes in technologically underdeveloped societies could be used as partial replacement of Portland cement to achieve this purpose. Efforts have recently been focused on such substitute materials in making cement composites such as concrete and sand Crete [
According to [
CaC 2 + 2 H 2 O → C 2 H 2 + Ca ( OH ) 2 (1)
Research findings have indicated that Calcium Carbide Waste, when combined with certain pozzolanas such as fly ash, silica fume, etc., containing high silicon dioxide and aluminum oxide could due to pozzolanic reactions yield final products that are like those obtained from cement hydration process. More researches are still being conducted on use of Calcium Carbide Waste in construction.
CaO + S i O 2 + H 2 O → C − S − H (2)
(Calcium Carbide Waste Powder) + (Bamboo Leaf Ash)
From Equation (2), it is observed that calcium carbide waste contains some cement chemical composition. Research findings have indicated that Calcium Carbide Waste, when combined with certain pozzolans such as fly ash, silica fume, etc., containing high silicon dioxide and aluminum oxide could due to pozzolanic reactions yield final products that are like those obtained from cement hydration process [
X-Ray Fluorescence Spectrometer is an effective non-destructive technique of analyzing the elemental and oxide crystal composition of a material [
This research is set out to investigate the use of the mix of an industrial waste, Calcium Carbide Waste Powder (CCWP) and an agricultural waste, Bamboo Leaf Ash (BLA) as partial replacement of cement in concrete, determine the compressive strength and workability of the concrete. This may be a cheaper alternative to conventional admixtures, which may lead to reduction in the cost of construction. This may also be a means of addressing the environmental pollution caused by the accumulation of the waste.
Aim and ObjectivesThe aim is geared towards using calcium carbide waste and bamboo leaf ash as partial replacement of cement in bid to achieve this aim, the specific objectives are to:
・ determine the chemical composition of calcium carbide waste powder (CCWP), bamboo leaf ash (BLA) and Ordinary Portland cement (OPC).
・ carry out compressive strength and other investigations on the concrete cubes that contain CCWP and BLA.
・ determine the interlocking property of concrete containing both wastes.
The materials used in this research work were Calcium carbide waste powder (CCWP), Bamboo leaf ash (BLA), sand (fine aggregate), granite (coarse aggregate), cement (OPC, Dangote type) and clean water for mixing as well as the curing medium. These materials were all gotten with Akure metropolis.
Sample Collection: Calcium carbide waste was collected from panel beaters’ workshops within Akure metropolis, sun-dried, grinded and sieved through British sieve 0.075 mm to produce the calcium carbide waste powder (CCWP) and Bamboo leaves were collected as the fall off from the main bamboo trees behind the students’ union building of federal university of technology Akure was collected. The bamboo dried bamboo leaves were dried and heated in the furnace to a temperature of 600˚C for 1hour to form BLA.
Methods of Physical Analysis: Particle size distribution analysis (with minimum sieves size 75 µm) as well as the hygrometer test were carried out for the fine aggregate obtained while aggregate crushing value (ACV) and aggregate impact value (AIV) tests were done for the granites. The particle size distribution curve for the fine aggregate was plotted.
Aggregate Crushing Value (ACV) Test: To determine the ACV for the granites, the aggregate passing through 12.5 mm and retained on 10 mm. British Standard (BS) sieve were oven dried at a temperature of 100˚C - 110˚C for 3 - 4 hours. The cylinder was filled in three layers, each layer tamped with 25 strokes of the tamping rod. The weight of the aggregate was measured and recorded as A. The surface of the aggregate was then leveled, and the plunger inserted. The apparatus was then placed in the compression testing machine and loaded at a uniform rate until the sample fails. The sample was then sieved through a 2.36 mm BS sieve and the fraction passing through the sieve was weighed as B. The ACV was calculated using Equation (3).
ACV ( % ) = ( B / A ) × 1 00 (3)
Aggregates impact Test: Also, the AIV test was done to determine the aggregate impact value of coarse aggregates according to [
AIV ( % ) = ( Y / X ) × 1 00 (4)
Methods of Chemical Analysis: Chemical tests were carried out on the CCWP and BLA to determine their chemical properties. Chemical analyses were conducted with the aid of X-ray fluorescence (XRF) spectrometry (XRF machine-Model X-supreme 8000 by Oxford instrument) and the various percentages of oxides present in the ash and powder were displayed on the screen as well as scanning electron microscope. Moisture content, soundness and loss of ignition tests were also carried out on these materials.
X-Ray Fluorescence Analysis: Mini Pal 4 Energy dispersive X-ray fluorescence (XRF) bench-top spectrometer was also used to perform nondestructive chemical analysis of elemental oxides present in the different wastes used. The CCWP and BLA were loaded into the sample holder and placed in the appropriate sample tray. The test was carried out by bombarding the samples with high energy X-rays which resulted into emission of characteristics secondary X-rays. Using silicon drift detector, the elemental analysis and oxide composition were determined and printed out through the attached computer and printer.
Scanning Electron Microscopic Analysis: In carrying out SEM analysis, the paste samples (of about 25 mm diameter) were prepared to fit in into the specimen chamber and they were mounted rigidly on the specimen stub. Their surfaces were polished to an ultra-smooth surface and were coated with carbon. Secondary electron detectors were used, and the data were displaced by a computer device.
Test: test was done by heating up CCWP and BLA to a temperature between 900˚C to 1000˚C until a constant weight was obtained. The test was conducted to determine the organic matter present in a sample. The weight of the various samples due to heating was then determined and recorded using Equation (5).
where; W1 = Weight of empty crucible (g), W2 = Initial weight (g) of crucible and sample before heating and W3 = Final weight (g) of crucible and sample after heating for 25 minutes and cooling for 20 minutes.
Loss on Ignition ( % ) = ( W 2 − W 3 ) / ( W 2 − W 1 ) × 100 (5)
Test and Analysis of Concrete Specimens: Concrete specimens of size 150 mm × 150 mm × 150 mm were produced by partially replacing OPC with CCWP/BLA at 0%, 5%, 10%, 15% and 20%. They were cured for 7, 21, 28 and 56 days in water and later brought out to be used for the compressive strength test in accordance with [
Compressive Strength and Bulk Density: Density of cubes was determined using Equation (6) and the compressive strength of 60 cubes was determined using Equation (7).
Materials | Quantities (kg) | ||||
---|---|---|---|---|---|
OPC (0%) | CCWP/BLA (5%) | CCWP/BLA (10%) | CCWP/BLA (15%) | CCWP/BLA (20%) | |
Cement (kg) | 12.50 | 11.88 | 11.25 | 10.63 | 10.00 |
BLA (kg) | 0.00 | 0.31 | 0.63 | 0.94 | 1.25 |
CCWP (kg) | 0.00 | 0.31 | 0.63 | 0.94 | 1.25 |
Water (kg) | 7.50 | 7.50 | 7.50 | 7.50 | 7.50 |
Sand (kg) | 25.00 | 25.00 | 25.00 | 25.00 | 25.00 |
Granite | 50.00 | 50.00 | 50.00 | 50.00 | 50.00 |
Water/cement ratio | 0.60 | 0.60 | 0.60 | 0.60 | 0.60 |
Tests | Duration (Days) | ||||
---|---|---|---|---|---|
7 | 21 | 28 | 56 | ||
Number of Specimen | CCWP/BLA 0% | 3 | 3 | 3 | 3 |
CCWP/BLA 5% | 3 | 3 | 3 | 3 | |
CCWP/BLA 10% | 3 | 3 | 3 | 3 | |
CCWP/BLA 15% | 3 | 3 | 3 | 3 | |
CCWP/BLA 20% | 3 | 3 | 3 | 3 |
Density of concrete ( kg / m 3 ) = M / V (6)
where; M = weight of dry concrete cube, V = Volume of dry concrete cube (150 mm by 150 mm by 150 mm).
Compressive Strength ( N / mm 2 ) = F / A (7)
where;
F = Crushing load (N);
A = Cross Sectional Area of the concrete cube in mm2 (150 mm by 150 mm = 22,500 mm2).
The results of the particle size distribution and the hygrometer test for sand (fine aggregate) is shown in
The X-ray fluorescence (XRF) spectrometry test was performed on the Calcium Carbide Waste Powder (CCWP), Bamboo Leaf Ash (BLA) and Ordinary Portland Cement (OPC). The result is given in
Physical Properties of All Materials Used | Fine Aggregate (Sand) | Coarse Aggregate (Granite) | Calcium Carbide Waste Powder (CCWP) | Bamboo Leaf Ash (BLA) | Ordinary Portland Cement (OPC) |
---|---|---|---|---|---|
Moisture content (%) | 0.47 | - | - | - | - |
Bulk Density (g/cm3) | 1.788 | - | - | - | - |
Silt/Clay Content (%) | 5.56 | - | - | - | - |
Fineness content (%) | - | - | 100 | 100 | 99.72 |
Soundness (mm) | - | - | <10 | <10 | <10 |
Specific Gravity | 2.64 | 2.61 | 2.93 | 2.32 | 3.13 |
AIV (%) | - | 19.78 | - | - | - |
ACV (%) | - | 30.48 | - | - | - |
Water Absorption (%) | - | 0.93 | - | - | - |
Loss on Ignition (%) | - | - | 16.62 | 5.23 | - |
pozzolan while Calcium Carbide Waste Powder doesn’t satisfy the requirement for a pozzolan (a non-pozzolan material). The chemical composition of the cement is also satisfactory and has met the standard [
Chemical Oxide | Percentage Composition (%) | ||
---|---|---|---|
BLA | CCWP | OPC | |
SiO2 | 67.41 | 6.69 | 22.00 |
Al2O3 | 1.95 | 2.30 | 3.11 |
Fe2O3 | 1.24 | 0.30 | 4.65 |
CaO | 16.99 | 89.76 | 62.00 |
MgO | 1.18 | ND | 2.06 |
MnO | 0.19 | ND | 0.32 |
ZnO | 1.18 | ND | 0.86 |
K2O | 1.27 | 0.09 | 0.40 |
LOI | 5.33 | 16.62 | - |
the maximum permissible value of 10% as specified by ASTM. This indicates that there is only very little unborn carbon, a substance which reduces the pozzolanic activity of the ashes if present in amounts greater than 10%. The pozzolanic activity of the investigated bamboo leaf ash is therefore not inhibited by the presence of unborn carbon.
As shown in
As shown in
% CCWP/BLA Replacement | Compressive Strength (N/mm2) | |||
---|---|---|---|---|
7 days | 21 days | 28 days | 56 days | |
5 | 9.57 | 10.60 | 12.07 | 15.17 |
10 | 9.93 | 11.83 | 13.23 | 15.97 |
15 | 8.07 | 10.97 | 11.90 | 14.10 |
20 | 7.23 | 9.70 | 10.50 | 12.87 |
concrete. These results show that some strength forming reactions takes place when these wastes were partially used to replace cement from 0% to 20%, after which the reactions reduces, and the compressive strength dropped. The phase of the optimum percentage replacement was studied using SEM studies.
The results of the setting times are shown in
Slump test result presented in
The results of the compaction factor tests performed in the fresh concretes are detailed in
From the chemical composition results in
S/N | Replacement (%) | Initial Setting Time (min) | Final Setting Time (min) |
---|---|---|---|
1 | 0 | 85 | 588 |
2 | 5 | 75 | 632 |
3 | 10 | 85 | 676 |
4 | 15 | 105 | 702 |
5 | 20 | 155 | 737 |
S/N | Percentage Replacement (%) | CCWP/BLA Slump Heights (mm) |
---|---|---|
1 | 0 | 58 |
2 | 5 | 59 |
3 | 10 | 61 |
4 | 15 | 58 |
5 | 20 | 54 |
S/N | Replacement (%) | L2-L1 |
---|---|---|
1 | 0 | 0 |
2 | 5 | 0 |
3 | 10 | 0 |
4 | 15 | 1.0 |
5 | 20 | 1.0 |
more than 4% would make the pozzolan to be unsound, was 1.18% in Bamboo Leaf Ash (BLA) which implies that it’s far less than 4% and not detected in Calcium Carbide Waste Powder, which implies that it could only be present in trace quantities. With this, it makes the replacements sound up to 20% replacement (no expansion or shrinkage is up to or above 10 mm.
L1 = Distance separating the indicator submerge in normal temperature water for 24 hours (mm). L2 = Distance separating the indicator submerge in boiling
for 3 hours (mm).
The dry densities of the concrete from the various mixes are presented in
The results of the SEM pictures for hydrated samples of OPC and CCWP/BLA 10% at 28 days curing are shown in
From the study, the following conclusions were drawn:
・ Oxide composition analysis of calcium carbide waste powder (CCWP) shows that CCWP is a no-pozzolanic material with high CaO content, and low SiO2
content, while bamboo leaf ash (BLA) is a pozzolanic material rich in silicon oxide (SiO2) component as shown in
・ Setting times of CCWP/BLA-cement combination increased with CCWP and BLA content in paste made with cement partially replaced with the two wastes.
・ Compressive strength results show that CCWP and BLA have positive effects on the strength of concrete made with the two wastes.
・ Compressive strength test result of concrete made exhibited great improvement with the addition of 10% CCWP/BLA after which a decline in compressive strength was observed.
・ Hence, the recommendation of a combination of 10% CCWP/BLA for use is in concrete products for construction, because peak compressive strength at this replacement level is comparable with result obtained with the use of only cement as binder.
・ Also, efforts should be made to keep CCWP and BLA sealed after grinding, sieving and burning. They should be kept in a dry area to prevent them from moisture attack, which may reduce its strength.
The authors declare no conflicts of interest regarding the publication of this paper.
Aderinola, O.S., Omolola, O.E. and Quadri, A.I. (2018) Effect of Calcium Carbide Waste Powder on Some Engineering Properties of Bamboo Leaf Ash Concrete. Open Access Library Journal, 5: e4990. https://doi.org/10.4236/oalib.1104990