Effect of polymer admixtures on flexural properties of preplaced aggregate concrete | |
| Author | Minsar, Mohamed Aslah Mohamed |
| Call Number | AIT Thesis no.ST-20-05 |
| Subject(s) | Aggregates (Building materials) Polymer-impregnated concrete Concrete--Mixing |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ST-20-05 |
| Abstract | This research is carried out to study the influence of different Polymer Admixtures in preplaced aggregate concrete on its Flexural Strength, and to identify the highest possible and economical Flexural Strength of preplaced aggregate concrete using polymer admixtures. Since the flexural strength of both conventional and preplaced aggregate concrete is mainly dependent on aggregate-grout bond strength, this research studies the aggregate-grout bond strength at the introduction of various polymer admixtures by conducting pull-off tests as the initial method to decide on the most effective polymer admixture to continue the experiments. Before the ignition of initial tests, fresh properties such as mini slump and flow time of grout was checked at the screening phase to ensure the sufficiency in flow and to fix the quantities of all the contents in the grout mix with due respect to past researchers. Grout materials such as the water, cement and sand were kept constant to evaluate performance at the initial stage and then upon the selection of the Polymer Admixture, 3 variable factors with 2k (two level full factorial) model with center points was selected for a different type of pull-off bond test; where k is the number of factors considered. Accordingly, pull-off test between the pressure washed exposed aggregate concrete surface with the selected polymer admixture added grout was evaluated. Based on the evaluation results, Compressive strength of grout and compressive strength of preplaced aggregate concrete are also checked along with flexural strength to develop relationships on selected mix designs. Finally, a pull-out test is also conducted between the PAC specimen and re-bar to understand the bonding strength of rebars with PAC on the same selections. The rate of superplasticizer was kept constant at 0.7 % from weight of binder to fulfil the water demand. To compare the experimental results of Polymer admixture added grout and PAC, a control mix design without any polymer admixtures and a past researcher’s mix design which gave the highest flexural strength using Silica Fume was separately casted in each type of tests. As a conclusion, it has been noted that Vinyl acetate copolymer dispersions performs better than styrene butadiene in all aspects and the flexure strength is almost same with the past researcher’s highest PAC strength obtained with Silica Fume. Also to be noted that curing conditions do play a major role on polymerization. |
| Year | 2020 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-20-05 |
| 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) | Punchet Thammarak;Thanakorn Pheeraphan (Co-Chairperson); |
| Examination Committee(s) | Pennung Warnitchai;Raktipong Sahamitmongkol; |
| Scholarship Donor(s) | Asian Institute of Technology Fellowship; |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2020 |