钢纤维增强粉煤灰自密实混凝土力学性能

Mechanical Properties of Steel Fiber Reinforced Fly Ash Self-compacting Concrete

采用粉煤灰取代40%水泥来制备粉煤灰自密实混凝土(SCC),研究其工作性、基本力学性能和轴压变形性能随钢纤维体积分数的变化规律.结果表明:粉煤灰SCC的工作性随钢纤维体积分数的增加而降低,当钢纤维体积分数大于0.75%时,粉煤灰SCC的工作性降幅最大;钢纤维体积分数对粉煤灰SCC抗压强度的影响不明显,但能够显著改善其劈裂抗拉强度和抗折强度,当钢纤维体积分数为1.00%时,劈裂抗拉强度和抗折强度较未掺钢纤维粉煤灰SCC分别提高了14%、12%;钢纤维能够显著改善粉煤灰SCC的轴压变形能力,当钢纤维体积分数为0.50%时,其极限应力、峰值应变、应变能和相对韧性与未掺钢纤维粉煤灰SCC相比,分别提高了3%、35%、53%和49%.

Fly ash self-compacting concrete(SCC)was prepared by replacing 40%cement with fly ash.Its workability,basic mechanical properties and axial compression deformation properties with the volume fraction of steel fibers were studied.The results show that the workability of fly ash SCC decreases with the increase of the volume fraction of steel fibers.When the volume fraction of steel fibers is more than 0.75%,the workability decreases most remarkable.The change of the volume fraction of steel fibers has slight effect on the compressive strength of fly ash SCC,but it can significantly improve its splitting tensile strength and flexural strength.When the volume fraction of steel fibers is 1.00%,the splitting tensile strength and flexural strength are increased by 14%and 12%respectively compared with SCC without steel fiber fly ash.The addition of steel fibers can significantly improve the axial compressive deformation properties of fly ash SCC.When the volume fraction of steel fiber is 0.50%,its ultimate stress,peak strain,strain energy and relative toughness are increased by 3%,35%,53%and 49%respectively compared with SCC without steel fiber fly ash.