Syntax Literate: Jurnal Ilmiah Indonesia p–ISSN:
2541-0849 e-ISSN: 2548-1398
Vol.
9, No. 5, Mei 2024
WORKABILITY INVESTIGATION ON THE FRESH MIX OF ECC MORTAR AND CRUMB RUBBER (CR)-ECC BASED ON VARIATIONS OF PALM SHELL ASH, RIVER SAND, AND CEMENT
Agussalim Lubis1,
Muhammad Aswin2, Gina Cynthia R. Hasibuan3
Universitas Sumatera Utara, Medan, Indonesia1,2,3
Email: [email protected]1,
[email protected]2
Abstract
Engineered
cementitious composite (ECC) is a composite that has better tensile properties
and behavior than concrete. ECCs are usually made of
cement, water, silica sand, cementitious materials, fibers,
and other additives. The term ECC mortar is used because the ECC does not use fiber. The cementitious material in this research uses palm
shell ash, with a proportion of 5%, 10%, and 15% of the cement weight. As a
replacement for the fiber, crumb rubbers are used,
with proportions of 2.5%; 5%; 7.5%; 10% and 12.5% of the cement weight.
Workability was measured based on slumpflow tests
(with measurements T500 and slumpflow diameter). The
objective of this study is to establish the workability of fresh mix of the ECC
mortar and CR-ECC with variations in the addition of palm shell ash, cement,
sand and crumb rubber. Based on the results of slumpflow
tests, the average diameter for fresh ECC mortars ranges between 88 cm to 106.5
cm, and the T500 ranges from 0.28 seconds to 1.39 seconds. As for fresh CR-ECC
mix, the mean slumpflow diameter is between 71 cm to
93 cm and the T500 ranging between 0.90 seconds and 1.68 seconds. All of these
values meet the slumpflow requirements stipulated by
EFNARC. Nevertheless, the workability of the fresh mix ECC mortar is more
flowable than the fresh mix CR-ECC. This is because crumb rubbers are
water-absorbing.
Keyword: ECC, cementitious
materials, palm shell ash, crumb rubber, workability
Introduction
Use of concrete in Indonesia is the
most widely used construction material because concrete has some advantages,
including that the materials are easy to obtain, easy to implement, fire
resistant and having a high compressive strength. Concrete is a type of
composite commonly used in construction which is made from a mixture of water,
cement, fine aggregates (sand), and coarse aggregate (usually gravel or crushed
stone) with a certain proportion, which forms a solid mass. Apart from having
advantages, concrete also has disadvantages, including low tensile and flexural
strength, causing the concrete to crack easily and also low ductility,
especially in earthquake-resistant structures.
Concrete researchers continue to
make innovations and technological developments in making efforts to improve
the quality and strength of concrete. One effort to improve the quality and
strength of concrete is to use engineered cementitious composites (ECC), which
is a composite that does not use coarse aggregate.
The building sector has become more
environmentally conscious and sustainable. Because of its resilience to cracks,
ductility, strength capacity, and self-healing ability, ECC is one of the
sustainable and environmentally friendly technologies that have the potential
to reduce the built environment's carbon and energy footprints. An attempt has
been made throughout the last 20 years to employ fibers,
fillers, and binders that are more environmentally friendly in order to produce
an ECC that is greener (Al-Fakih
et al., 2021; Hau Hong et al., 2020; Shoji et al., 2022). These initiatives fit under a
number of categories.
ECC was first discovered by Victor
C. Li in the early 1990s at Michigan University, USA. Li et al. (1993) and Li (1993) developed ECC based on
micromechanical principles, fiber crack bridging behavior, multiple cracks, and apparent strain hardening.
In developing ECC, fundamental approaches generally aim to produce reciprocal
mechanical interactions between fiber, matrix, and fiber-matrix interface, as well as to increase ductility
and tensile strength. The fiber content will be 2% or
less based on volume fraction (Li,
1993, 2008). High volume fly ash and micro-silica sand are always
utilized to support the unique behavior of ECC. The
adjusted SP is used to control the workability of ECC (Wang
& Li, 2007). Due to its adverse impact on the
unique behavior of the composite, coarse aggregate is
not used in ECC mixtures. In general, the ECC composition consists of a
water-cement ratio and a sand-cement ratio of 0.5 or lower, where the cement
content is less than 600 kg/m3. Apart from that, the typical fiber used is polyvinyl alcohol (PVA), but other fibers can also be used such as high strength polyethylene
(PE) fiber or polypropylene (PP) fiber
(Fischer
& Shuxin, 2003; Li & Wang, 2002). The main mechanical properties of
ECC are shown in Table1 (Li,
2008).
Table 1. The main mechanical properties of ECC (Li, 2008)
|
Compressive |
Fist Crack |
Ultimate Tensile |
Ultimate Tensile |
Young's |
Flexural |
Density |
|
Strength |
Strength |
Strength |
Strain |
Modulus |
Strength |
|
|
(MPa) |
(MPa) |
(MPa) |
(%) |
(GPa) |
(MPa) |
(kg/m³) |
|
20-95 |
3-7 |
4-12 |
1-8 |
18-34 |
10-30 |
950-2300 |
Aswin et al. (2024) has developed ECC using local
river sand, silica fume, medium to high-volume fly ash (FA) and polyvinyl
alcohol fiber (PVA), by evaluating workability and
strong pressure at test life (1, 7, 28, 60, and 180 days). All ECC samples had
a strong pressure of more than 20 MPa after 1 day,
while the strongest pressure after 28 days was 111.28 MPa.
Liew et al. (2020) revealed that ECC fresh mix must
have high workability. However, the use of volume fraction of PVA fiber causes a decrease in workability. This is due to the
hydrophilic nature of PVA fiber. This deterioration
is clearly seen when the volume fraction reaches 2% or more. Furthermore, Zhao
et al. (2023) reported that the use of fly ash
and crumb rubber in the ECC mix results in increased ductility, a denser
fracture pattern, and decreased permeability.
Global cement production exceeds 4
billion tons per year, accounting for around 8% of CO2 emissions (Lehne
& Preston, 2018; Summerbell et al., 2016). Thus, the purpose of this study
is to investigate the fresh performance and workability of ECC mix with a low
cement content (less than 400 kg/m3) and the creation of a green ECC by the
utilization of waste materials like crumb rubber and palm shell ash.
A study of the workability of the
ECC mortar and crumb rubber ECC mix is important, because the target for using
ECC mix in the field is that fresh ECC mix can flow and consolidate itself
without using a vibrator. In this study, the workability of fresh ECC mix was
only considered based on the slump flow diameter and T500 only. Apart from
that, the differences in workability that occur between fresh ECC mortar mix
and the ECC fresh mix using crumb rubber (CR-ECC) will also be evaluated.
Research Methods
Materials
and Equipment
Preparation of materials and
equipment can be used to make or form ECC and CR-ECC mortars are cement, water,
sand, palm shell ash, superplasticizer and crumb rubber. The cement used is OPC
with Type-1. Palm shell ash is obtained from plantations in Serdang Bedagai Regency, North Sumatra Province which is produce
from the burning process and only uses palm shell ash that passes filter no. 30
or 0.6 mm diameter. Furthermore, the procurement of equipment used in making ECC
mortar is scales, mixer drills, slump test equipment, flowability test
equipment, measuring meters, etc.
Mix
Design
Mix design is the process of
determining the right proportion (composition) to achieve the desired
properties in a mixture or mortar in order to produce a mixture that meets the
desired technical requirements. In this research, mix design was carried out
using the addition of crumb rubber material and without crumb rubber. The
composition of the mixture without crumb rubber is coded Type-1, namely AME,
EM, TEM, and the composition of the mixture with crumb rubber is coded Type-2,
namely FRC, CRE, TCRE.
The mix proportion of ECC mortar
(Type-1: AME, EM, TEM) is made based on trial and error in the lab, as well as
referring to related references. Meanwhile, the Crumb Rubber ECC mix proportion
(Type-2: FCR, CRE, TCRE) is taken with the ECC mortar mix proportion which
produces the highest compressive strength value. The ECC mortar mix proportion
can be seen in Table 2, and for CR-ECC is shown in Table 3.
Table 2. Mix Proportion of ECC Mortar
|
Code Specimen |
Cement (kg) |
Ash
Shell Palm (kg) |
Water (kg) |
Sand (kg) |
Super plasticizer (kg) |
Crumb rubber (kg) |
|
AME 0% |
10.720 |
- |
4.449 |
11.792 |
0.075 |
- |
|
AME 5% |
10.467 |
0.523 |
4.344 |
11.513 |
0.167 |
- |
|
AME 10% |
10.239 |
1.024 |
4.249 |
11.263 |
0.256 |
- |
|
AME 15% |
10.011 |
1.502 |
4.155 |
11.012 |
0.34 |
- |
|
EM 0% |
10.382 |
- |
4.360 |
10.382 |
0.073 |
- |
|
EM 5% |
10.134 |
0.507 |
4.256 |
10.134 |
0.162 |
- |
|
EM
10% |
9.898 |
0.99 |
4.157 |
9.898 |
0.247 |
- |
|
EM
15% |
9.673 |
1.451 |
4.063 |
9.673 |
0.329 |
- |
|
TEM 0% |
10.275 |
- |
4.624 |
10.275 |
0.072 |
- |
|
TEM 5% |
10.034 |
0.502 |
4.515 |
10.034 |
0.161 |
- |
|
TEM 10% |
9.803 |
0.98 |
4.411 |
9.803 |
0.245 |
- |
|
TEM 15% |
9.583 |
1.437 |
4.312 |
9.583 |
0.326 |
- |
Table 3. Mix Proportion of CR-ECC
|
Code Specimen |
Cement (kg) |
Ash Shell Palm (kg) |
Water (kg) |
Sand (kg) |
Super plasticizer (kg) |
Crumb rubber (kg) |
|
FCR 0% |
10.239 |
1.024 |
4.249 |
11.263 |
0.256 |
- |
|
FCR 2,5% |
10.149 |
1.015 |
4.212 |
11.164 |
0.254 |
0.254 |
|
FCR 5% |
10.043 |
1.004 |
4.168 |
11.047 |
0.251 |
0.502 |
|
FCR 7,5% |
9.996 |
0.996 |
4.134 |
10.957 |
0.249 |
0.747 |
|
FCR 10% |
9.866 |
0.987 |
4.094 |
10.852 |
0.247 |
0.987 |
|
FCR 12,5% |
9.779 |
0.978 |
4.058 |
10.757 |
0.244 |
1.222 |
|
CRE 0% |
9.898 |
0.99 |
4.157 |
9.898 |
0.247 |
- |
|
CRE 2,5% |
9.802 |
0.980 |
4.117 |
9.802 |
0.245 |
0.245 |
|
CRE 5% |
9.707 |
0.971 |
4.077 |
9.707 |
0.243 |
0.485 |
|
CRE 7,5% |
9.615 |
0.961 |
4.038 |
9.615 |
0.240 |
0.721 |
|
CRE 10% |
9.524 |
0.952 |
4.000 |
9.524 |
0.238 |
0.952 |
|
CRE 12,5% |
9.435 |
0.944 |
3.963 |
9.435 |
0.236 |
1.179 |
|
TCRE 0% |
9.803 |
0.98 |
4.411 |
9.803 |
0.245 |
- |
|
TCRE 2,5% |
9.709 |
0.971 |
4.369 |
9.709 |
0.243 |
0.243 |
|
TCRE 5% |
9.615 |
0.961 |
4.327 |
9.615 |
0.240 |
0.481 |
|
TCRE 7,5% |
9.524 |
0.952 |
4.286 |
9.524 |
0.238 |
0.714 |
|
TCRE 10% |
9.435 |
0.944 |
4.246 |
9.435 |
0.236 |
0.944 |
|
TCRE 12,5% |
9.347 |
0.935 |
4.206 |
9.347 |
0.234 |
1.168 |
The
Fresh Mix of ECC Mortar and Crumb Rubber-ECC
All related ingredients are mixed
in a dry container, then stirred thoroughly until the desired mixture
consistency is achieved. The mixing process usually takes about 10-12 minutes.
Then the fresh mixture of ECC mortar or CR-ECC is put into the Abrams cone and
lifted slowly. Next, the flowability time (T500) and the average diameter of
the fresh mix distribution were measured. The procedure for implementing the
workability test can be seen in Figure 1.
Figure 1. Workability test of the fresh ECC
mortar and CR-ECC mix
Results and
Discussion
Based on the results of workability
testing on the fresh ECC mortar mix (Type-1: AME, EM and TEM) and CR-ECC mix
(Type-2: FCR, CRE and TCRE), the flowability value T500 and the average slumpflow diameter are obtained, as shown in Figure 2-5.
Figure 2. Slumpflow T500 of fresh ECC mortar
Figure 3. Slumpflow diameter of fresh ECC mortar
Figure 4. Slump flow
T500 of fresh CR-ECC mix
Figure 5. Slump flow
diameter of fresh CR-ECC mix
Based on the workability test
results, it can be seen that all fresh ECC mortar mix and CR-ECC mix showed the
good workability, and are in accordance with the provisions of EFNARC. However,
the workability of fresh ECC mortar is more flowable than fresh mix of CR-ECC.
This is because crumb rubber absorbs water.
Conclusion
The workability of the fresh ECC
mortar is better than the fresh mix of CR-ECC. This is because the CR-ECC
contains the crumb rubber which absorbs water, thus causing a reduction in the
workability value of the fresh CR-ECC mix.
BIBLIOGRAPHY
Al-Fakih, A., Mohammed, B. S., & Liew, M. S. (2021). On
rubberized engineered cementitious composites (R-ECC): A review of the
constituent material. Case Studies in Construction Materials, 14,
e00536.
Aswin, M., Özkılıç, Y. O., Aksoylu, C., & Al-Fakih, A.
(2024). Evaluating Bulky PVA-ECC Mortar Developed with River Sand, Silica Fume,
and High-Volume Fly Ash: A Focus on Short-and Long-Term Compressive Strength. Arabian
Journal for Science and Engineering, 1–19.
Fischer, G., & Shuxin, W. (2003). Design of engineered
cementitious composites (ECC) for processing and workability requirements. In Brittle
matrix composites 7 (pp. 29–36). Elsevier.
Hau Hong, D. L., Mohammed, B. S., Al-Fakih, A., Wahab, M. M.
A., Liew, M. S., & Amran, Y. H. M. (2020). Deformation properties of
rubberized ECC incorporating nano graphene using response surface methodology. Materials,
13(12), 2831.
Lehne, J., & Preston, F. (2018). Making concrete change. Innovation
in Low-Carbon Cement and Concrete.
Li, V. C. (1993). From micromechanics to structural
engineering-the design of cementitous composites for civil engineering
applications.
Li, V. C. (2008). Engineered cementitious composites (ECC)
material, structural, and durability performance.
Li, V. C., Stang, H., & Krenchel, H. (1993).
Micromechanics of crack bridging in fibre-reinforced concrete. Materials and
Structures, 26, 486–494.
Li, V. C., & Wang, S. (2002). Flexural behaviors of glass
fiber-reinforced polymer (GFRP) reinforced engineered cementitious composite
beams. Materials Journal, 99(1), 11–21.
Liew, M. S., Aswin, M., Danyaro, K. U., Mohammed, B. S.,
& Al-Yacouby, A. M. (2020). Investigation of fibers reinforced engineered
cementitious composites properties using quartz powder. Materials, 13(11),
2428.
Shoji, D., He, Z., Zhang, D., & Li, V. C. (2022). The
greening of engineered cementitious composites (ECC): A review. Construction
and Building Materials, 327, 126701.
Summerbell, D. L., Barlow, C. Y., & Cullen, J. M. (2016).
Potential reduction of carbon emissions by performance improvement: A cement
industry case study. Journal of Cleaner Production, 135,
1327–1339.
Wang, S., & Li, V. C. (2007). Engineered cementitious
composites with high-volume fly ash. ACI Materials Journal, 104(3),
233.
Zhao, Y., Chen, X., Wang, Z., Zhang, Y., & Leng, Y.
(2023). An experimental study on the influence of fly ash and crumb rubber on
the mechanical property and permeability of Engineered Cementitious Composite
(ECC). Journal of Building Engineering, 76, 106998.
|
Copyright
holder: Agussalim Lubis,
Muhammad Aswin, Gina Cynthia R. Hasibuan (2024) |
|
First
publication right: Syntax Literate: Jurnal
Ilmiah Indonesia |
|
This
article is licensed under:
|
