| Title |
A Study on the Physical Properties of Polymer Cement Mortar as Restorative Materials by Formation of Raw Materials |
| Authors |
Lee Mun-Hwan ; Song Tae-Hyeob |
| Keywords |
Repair Method ; Restorative Mortar ; Polymer ; Reinforcing Fiber ; Material Mix Design |
| Abstract |
Restorative mortar of which main materials are cement employs and makes diverse combined materials for better performances in site work conditions. Many factors including setting time, stream, work, and conveyance are able to work as components of materials and the amount of rebound and the efficiency of adhesion in construction works as main factors of materials.This study is intended to compare and analyze performances of which mortar combination is suitable to spray in restoration works for concrete. For this, it sets out the combination of cement, powder-type EVA polymer and reinforced fiber and changes the factors of raw materials by two to compare performances. The results of the study show that properties of raw materials of restorative mortar are as follows.Shape of fine aggregate is similar to round type and bending force and rate of change in length are stable, while one of natural aggregates is not regular and provides with lower physical properties. Anhydrite gypsum used to ensure initial strength alters in performances as connected with using superplasticizer. Specifically, polycarbonate-based and melamine-based superplasticizers are substantially unavailable to molding of product due to fast hardening and dehydration. The study has identified that additional CSA is able to control initial strength but is lower in rate of change in length and stability than alumina cement mixtures. The measurement of fiber types shows that the length of mixture of PP fiber changes smoothly, which indicates that PP fiber with lower specific gravity is relative higher depending on mixing rate by weight ratio. Mixing of PP fiber, therefore, does not improve the strength due to pull-out under strong external force like bending force but is excellent in cohesion for longer period like drying shrinkage. |