The document summarizes a study on the behavior and use of waste concrete from demolition sites. It discusses: 1) Large amounts of concrete debris were generated from earthquake damage in Nepal, which is difficult to decompose. 2) Testing showed that replacing up to 15% of fine aggregate in new concrete with recycled concrete aggregate can increase the compressive strength by about 12%. 3) Using recycled concrete aggregate is beneficial as it reduces environmental impacts from extracting new aggregates and solves the problem of disposing waste concrete.

1. Behaviour of Waste Concrete
Debris in Concrete
Participants
Saurav Shrestha
Sujan Maharjan
Nishma Karki
Er. Suraj shah
Department of Civil Engineering
Khwopa College of Engineering
Nepal

2. • Introduction and need of the study
• Literature review
• Methodology and Material Specifications
• Result
• Conclusion
• Recommendations
Prepared by: Saurav Shrestha
Khwopa College of Engineering

3. • Complete or partial destruction of over 600,000 houses following
earthquake of April 25 and May 12,2015 (as per codeofnepal.org)
• Results in large quantities of solid waste named concrete debris
• Also caused as a result of demolition of houses after it comes of age or
any other reasons
• Very hard to decompose
• Continuous extraction of natural aggregates from riverbeds, lakes and
other water bodies results in huge environmental problems
• May serve as an alternative for replacement of these aggregates
Prepared by: Saurav Shrestha
Khwopa College of Engineering

4. • The recycled aggregates are either used as fine recycled or coarse
recycled
• In some studies, increase in percentage of recycled aggregate
increased the strength of concrete to some extent and then decreased
on further increase (Marzouk and Azab,2014)
• In others, it was found that the increase in percentage of recycled
aggregate resulted in a fraction decrease in the strength of concrete
(Mohd Monish, 2014)
• Either way the study showed promising results
Prepared by: Saurav Shrestha
Khwopa College of Engineering

5. • Collection of construction debris from demolition site
35 years old
M20 concrete
Partially destroyed by earthquake of April,2015
• Ramming the collected construction debris to get fine recycled
aggregates (0.075 mm-4.75 mm)
Prepared by: Saurav Shrestha
Khwopa College of Engineering

6. • Calculation of specific gravity of fine, coarse aggregate, cement and
recycled aggregate
Pycnometer Test Material
type
Size
(mm)
Specific
gravity
Fine
aggregate
<4.75 2.61
Coarse
aggregate
<20 and >
4.75
2.76
Cement - 3.10
Debris (35
years old)
<4.75 2.48
Prepared by: Saurav Shrestha
Khwopa College of Engineering

7. • Mix proportion calculation based on IS method(M20 grade)
Water Cement FA CA
In kg/cu.m 180.42 360.84 594.60 1263.83
In
Proportion
0.50 1.00 1.65 3.50
w/c=0.5
Prepared by: Saurav Shrestha
Khwopa College of Engineering

8. • Cube preparation
Size 15cm*15cm*15cm
Percentage of (0%,5%,15%,25%,35%,50%) replacement of fine aggregate
with recycled aggregate
18 cubes (3 for each proportion)
The one with 0% replacement was taken as standard
• Curing and testing after 28 days
• Study, analysis and documentation of data in terms of compressive, flexural
and tensile strength
Prepared by: Saurav Shrestha
Khwopa College of Engineering

9. Fig.2 Compressive Strength test in UTMFig.1 Cube samples prepared with percentage of
respective recycled aggregate content
Prepared by: Saurav Shrestha
Khwopa College of Engineering

10. Fig. Compressive strength(N/𝑚𝑚2) vs
percentage of aggregate replacement
• The optimum amount of
replacement was 15%,
• about 11.85% of
increment in strength
Prepared by: Saurav Shrestha
Khwopa College of Engineering

11. Fig. Flexural strength (N/𝑚𝑚2
) and percentage of debris
replacement
Fig. Tensile strength (N/𝑚𝑚2
) vs. percentage of
replacement
Flexural strength is calculated referring relevant
clause fcr = 0.7 (fc) ^0.5) from 6.2.2: IS 456 – 2000
Tensile strength is calculated from an expression ft = 0.12
(fc) ^0.7 used in British Code of practice BS 8007:1987
Flexural
Strength
% of
replacement
Prepared by: Saurav Shrestha
Khwopa College of Engineering

12. • Very little difference in changes in flexural and tensile strength so,
compressive strength is primary basis
• The optimum amount of replacement was 15%,
-about 11.85% of increment in strength
• Excellent replacement for fine aggregate in the concrete mix
• Solves indisposable problem of waste concrete debris due to
earthquake and demolition
• Promotes environmental balance by reducing excavation of
aggregates
• Tool in Post Disaster Reconstruction Planning
Prepared by: Saurav Shrestha
Khwopa College of Engineering

13. • Reasons for varying result with literature review maybe due to
Varying age of concrete(concrete after completing life shows lesser
strengths)
Grade of concrete used
Region of construction
Rate of water absorption
Prepared by: Saurav Shrestha
Khwopa College of Engineering

14. • Testing of concrete may also be done by
 varying grain size
 varying water cement ratio and
 modifying properties of waste concrete to study variations
• Chemical analysis of concrete debris in concrete
Bonding
Prepared by: Saurav Shrestha
Khwopa College of Engineering

15. References
• Seeni, A., Selvamony, C., Kannan, S.U & Ravikumar, M.S. (2012) .Experimental study of partial replacement of fine aggregate with
waste material from china clay industries. International journal of computational Engg. Research, 2(8), 167-171.
• Al-Jaberi, L. (2018). Effect of Grinded of Debris of Concrete on the Compressive Strength of Reactive Powder Concrete. Journal of
University of Babylon for Engineering Sciences, 26(8), 218 - 227. Retrieved from
https://www.journalofbabylon.com/index.php/JUBES/article/view/1612 26
• . Poovendiran, K., Mariappan, P., Thivya, J., & Jayganesh, D. (2015). Recovery and reuse of fine aggregate from debris of building
demolition. International Journal of Engineering and Technology (IJET), 7(1), 222-233.
• Li, X. (2008). Recycling and reuse of waste concrete in China: Part I. Material behavior of recycled aggregate concrete .Resource
Conservation Recycle, 53(3), 36–44.
• Mahzuz, H.M.A., Ahmed A.A.M., & Yusuf M.A. (2011). Use of stone powder in concrete and mortar as an alternative of sand,
African journal of Environmental Science and Tech,5(5), 381-388.
• Miguel Blanco-Carrasco, F. H. N. O. (2010), Qatar: Green Concrete Technologies-Towards a Sustainable Concrete Industry in Qatar
• Asutkar, P., Shinde, S., & Patel, R. (2016). Study on the Behaviour of rubber aggregates concrete beams using analytical approach.
Engineering Science and Technology, an International Journal.20. 10.1016/j.jestch.2016.07.007.
• Wu, B., Yong, Y., &Zongping, C. (2018). Compressive Behaviors of Prisms Made of Demolished Concrete Lumps and Fresh Concrete.
Applied science, 8(5), 1-21
Prepared by: Saurav Shrestha
Khwopa College of Engineering

16. ACKNOWLEDGEMENT
• Entire ICEE-PDRP committee
• Entire family of Khwopa College of Engineering
• Shivaram Suwal sir
• Friends and companions
Prepared by: Saurav Shrestha
Khwopa College of Engineering

17. Prepared by: Saurav Shrestha
Khwopa College of Engineering