Development of rapid setting and self levelling repair mortar | |
| Author | Sultana, Jennifar |
| Call Number | AIT Thesis no.ST-21-17 |
| Subject(s) | Mortar--Additives Composite materials--Compression testing |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | The purpose of this thesis was to come up with a mix design to obtain a self-levelling, rapid-setting repair mortar. Based on literature research, pre-screening tests, and supplier recommendations, the amount of cement, silica fume, and superplasticizer used in this study was carefully determined to obtain the ideal fresh properties of self levelling mortar and desired compressive strength at 6 hours. The challenge was to provide a mix that is self-levelling in nature with high compressive strength at 6 hours and flexural strengths in 1 day and with adequate bond strength between the new repairing material and the old substrate. Two level full factorial design (2k) with 4 centre points was adopted to analyse the results where k is the number of factors. A constant amount of superplasticizer (Mighty 150 SA-5) which 1.75% by the weight of cement and accelerator (SikARapid-1) which 4% by the weight of cement was used for the entire experiment process. Cement was fixed for 400 kg/m3. 20 experiments were carried out and the obtained results were analysed by Minitab19 software. All the 20 mixes were levelling in nature and gave rapid setting properties with varying fresh and hardened properties. It was observed that in fresh properties higher percentage of silica fume has a negative impact and in hardened properties it shows a positive impact. Addition of 10 % silica fume increases the bond strength and give the highest strengths. Lower amount of water-binder ratio give higher strengths in hardened properties. The expansive agent plays a positive role in fresh properties but in case of hardened properties it reduces their strength with the increasing amount of CSA(calcium aluminate additive. The drying shrinkage was found to be under acceptable limits i.e. 500 microstrain at 28 days due to the application of CSA. |
| Year | 2021 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pennung Warnitchai;Thanakorn Pheeraphan (Co-Chairperson) |
| Examination Committee(s) | Punchet Thammarak;Anwar, Naveed |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2021 |