PERFORMANCE OF CONCRETE WITH RECYCLED CRUSHED GLASS AS A SUBSTITUTE FOR NATURAL SAND
INTRODUCTION
The aim of the research dissertation is to examine the concrete workability and performance which is prepared with RCG instead of sand. It is a substitute Materials to recycle waste and reduce the consumption of natural sand. Project objectives are:
1) Examine concrete workability with RCG and investigate it as a natural sandreplacement. 2)
MIX DESIGN
Experiment Methodology
The experiment plan is divided into the following stages:
Resource Planning
Indirect Tensile Strength Test
Flexural or Bending Strength Test
TABLES, FIGURES AND EQUATIONS
Cylinder
Beam
Figure 3.2 Beam Design from AutoCAD
Table 3.2: Rectangular Beam Mold Parameters
| Rectangular Beam Mould Parameters | |
|---|---|
| Height (m) | 0.15 |
| Width (m) | 0.15 |
| Length (m) | 0.51 |
| Volume (m3) | 0.0115 |
| Number of Molds | 10 |
| Total Volume | 0.1148 |
| Total Concrete Required | 275.40 |
3.3 Equations Used.
A = cross-sectional area of specimen (mm2)
Splitting Tensile Strength
D = diameter of specimen (m)
Maximum Bending Moment
RESULT AND OBSERVATION
Compressive Strength Test
𝑀max
𝑃 ∗ 𝐿 = 𝑃𝐿
Flexural Strength
𝝈 = 𝑴 = 𝑴𝒂𝒙𝒊𝒎𝒖𝒎 𝒃𝒆𝒅𝒊𝒏𝒈 𝒎𝒐𝒎𝒆𝒏𝒕 = 𝑴
𝒀 𝒅⁄𝟐
=𝒃𝒅𝟐
modes. Then, according to the chart, we can see cracks and a graphic of typical fracture patterns. From the table, we can see the failure mode of our cylinders. Depending on the Batching mix, this failure mode type was altered. We discovered some compressive strength test data as a result of this. The numerous sizes and types of cracks can be seen here. We may deduce from the potential failure that the cylinder's strength is higher than normal compressive strength, but because we can see the break, we can calculate the average compressive strength test result and determine the cylinder's failure mode from of the tables.
We substituted sand with various sizes of glass; after putting 40% glass and 60% sand to specimens 2,3, and 4, the compressive of the cylinder was decreased compared to Control mixture 1 as there was no glass in the control specimen and I used 100% sand instead of glass. Also, in specimen 1, I used 80 percent cement and only 20% fly ash, which boosted compressive strength when compared to the other four specimens, but in the other four specimens, I applied more than 20% fly ash instead of cement as a cementitious material.
Indirect Tesnile Strength
18 cylinders from each batch. Each batch has various materials, and we tested eight cylinder for ultimate load carrying capacity. Those all cylinders were displaying different findings, and during the test, we applied a 2.4 KN/s load and obtained data from the various channels utilising the SANS machine. I recorded various data from the tests, including deflection, load, and duration.
After gathering this information, I utilised a formula to compute average tensile, as well as variance using average mechanical properties so each cylinder's tensile strength. After adding split tension force, I can see a crack on the cylinder. These fissures revealed the cylinder's failure mode. In the diagram, we can identify typical fracture patterns.
As a result, specimen 1 has a high average tensile strength, however specimen 2 has a lower average tensile strength since I used 30% fly ash as a cement replacement and 40% glass rather than just 100% sand. As a result, we can see in the Average tensile strength graph that the maximum compressive strength is constantly decreasing, while it suddenly increases in specimen 4 but we used 30% fly ash and 15% slag instead of 100% solidify and 40% RCG instead of 100% sand, that also increased the tensile strength of the concrete to nearly 2.41 MPa.
Various sorts of fracture patterns in the cylinder were caused by the variable average tensile strength. The cracks in the cylinders can be seen in the photograph, and the failure mode of specimen 1 cylinder is type 1 since the cylinder fracture through to the caps. The failure modes of the second specimen cylinders are type 3 and type 4. We can detect failure patterns such as type 3-vertical crack extending through the cylinder cap and type-4 diagonal fracture with no cracking through the ends from the photograph. Because each of the five examples has a distinct fracture pattern, we can readily determine which cylinders has the maximum tensile strength.
Bending Strength Test
To begin, we determined the bending moment. We used flexural strength formulas after obtaining the
maximum bending moment: moment divided by cross - section area. All of these computations resulted in the beam's flexural strength.
Fig 4.4Beam esult of Bending Strength Test
CONCLUSION
To conclude that adding recycled crushed glass in the replacement of sand that is best composition in concrete mix which increase strength of concrete while, adding many different cementitious Materials such as fly ash, slag, and silica fume which affected concrete strength and workability. After performing three tests compressive, tensile, and flexural strength tests; after calculating strength and compared with normal 32 MPa strength; we can see that cementitious materials are resisting alkali silica reaction, but it is decreasing compressive, tensile and flexural strength. While, adding glass is improving strength of concrete so we can add glass in more proportion in replacement of sand.
REFERENCES
Byars, E.A, Morales-Hernandez, B & Ying, Z.H 2004, ‘Waste glass as concrete aggregate and pozzolan - laboratory and industrial projects’, Concrete, vol. 38, pp. 41–44.
Can ham, I, Page, C.L & Nixon, P.J 1987, ‘Aspects of the pore solution chemistry of blendedcement related to the control of alkali-silica reaction', Cement and Concrete Research, vol. 17, no. 5, pp. 839-844.