不同应力状态下无机聚合物的破坏模式与力学特性研究-台北科技大学.PDF

不同應力狀態下無機聚合物的破壞模式與 力學特性研究* Failure Modes and Mechanical Characteristics of Geopolymers Under Variying Confining Pressure 1 2 3 4 5 1 2 3 4 5 S.J. Lyu , Y.H. Hsiao , T.T. Wang , T.W. Cheng , T.H. Ueng SiO /Na O This research condu cted uniaxial compression and 2 2 triaxial compression tests on geopolymers under varying confining pressures. The geopolymers were prepared with comp ounds having variou s SiO /N a O mole ratios. The 2 2 purpose was to investigate the associated failure modes and mechanical characteristics under different stresses. Experiment results showed that under the uniaxial compressive condition the geopolymer specimen failed in a splitting mode as a brittle material. As the confining pressure increased, failure mode changed to mono shear crack, conjugated shear crack, or bulge SiO /Na O failure with an increasing failure strain. The apparent cohesion 2 2 of geopolymer decreased when SiO /Na O mole ratio was 2 2 SiO /Na O increased. For geopolymer with similar failure mode, the 2 2 apparent friction angle increased as the SiO /Na O mole ratio 2 2 was increased. A significant reduction can be observed as SiO /N