Study on Fracture Energy and Uniaxial Compressive Behavior of Mortar Made with No-Cement Eco-Binder

• Main Authors: Chiao-Wei Yang, 楊巧薇
• Other Authors: Ta-Peng Chang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/ys7bzx

碩士 === 國立臺灣科技大學 === 營建工程系 === 106 === This study aims to investigate engineering properties, stress-strain relationship, and the fracture energy of mortar made with no-cement binder. The fracture energy was measured by three point bending (TPB) tests which were carried out on various notched beams, as recommended by RILEM based on Size Effect Law (SEL), and the test result were compared with those of mortar specimens of ordinary Portland cement (OPC) having similar compressive strengths. No-cement binder was denoted as SFC binder, which was made by three kinds of blended industrial solid wastes of ground granulated blast furnace slag (GGBFS/slag), Type F fly ash (FFA), and circulating fluidized bed combustion (CFBC) fly ash. Experimental results showed that: (1) For specimens with similar 28-day compressive strength, the early strength of SFC mortar specimen was lower than that of OPC mortar, but their later strengths were similar; (2) The elastic moduli of SFC mortar were higher than those of the OPC mortar at the similar compressive strength by 15% and 23%, for the low-strength group and high-strength group, respectively. (3) The peak strength of SFC mortar with water-to-binder (W/B) ratio of 0.25 was increased by 85% as compared with that of 0.35. (4) The peak strains of SFC mortar were in the range of 0.00279 to 0.0042, where peak strains were higher by 27% for low-strain group and lower by 32% for high-strength group as compared with those of OPC mortar. (5) The post peak behavior of stress strain relationship of SFC mortar showed more brittle behavior than that of OPC mortar with similar compressive strength. (6) ClassⅡsnap-back failure mode only happened when the compressive strength of SFC mortar higher than 60 MPa in this research; (7) The splitting strengths of SFC and OPC mortar had similar results at similar compressive strength, in which the difference of 3% and 10% occurred to the low-strength group and high-strength group, respectively. (8) For the TPB specimens with the initial crack widths of 2 mm and 4 mm, respectively, the resulting differences were between 4% and 12% for peak load and about 23% for fracture energy; (9) For SFC mortar, the increment of compressive strength by 80% and 98% induced the fracture energy increase by 76% and 225%, respectively. On the other hand, compressive strength increase by 29% and 75% as fracture energy decrease by 15% and 33%.