SAP与硅灰复掺对水泥强度与电阻率的影响

The Effects of SAP and Silica Fume on Strength and Electrical Resistivity of Cement Paste

研究了高吸水树脂(SAP)和硅灰复掺对水泥浆体凝结时间、抗压强度、电阻率和温度等的影响。结果表明:SAP的掺入降低了试块的抗压强度,SAP掺量为0.4%时,随着硅灰掺量的增大,硬化水泥浆体的3 d抗压强度逐渐降低,但28 d抗压强度逐渐增大;SAP能延长水泥浆体的凝结时间,硅灰则缩短水泥浆体的凝结时间;不同掺量SAP和硅灰的水泥浆体电阻率变化曲线具有相同的变化趋势,SAP能明显降低水泥浆体12 h龄期后的电阻率,而硅灰能降低水泥浆体24 h龄期后的电阻率;随着SAP掺量的增加,水泥浆体内部温度峰值逐渐降低,而随着硅灰掺量的增加,水泥浆体内部温度峰值先增加后降低。

The effects of super absorbent polymer（SAP） and silica fume on the setting time, compressive strength,electrical resistivity and temperature of cement paste were studied. The results show that the SAP reduces the compressive strength of the cement pastes, when the content of SAP is 0.4%, the 3 d compressive strength of hardened cement paste decreases gradually with the increase of silica fume, but the compressive strength of 28 d gradually increases. SAP can extend the setting time of the cement paste, but the silica fume can shorten the setting time of the cement paste. The electrical resistivity of cement paste with different SAP and silica fume content have the same trend with time, SAP can obviously reduce the electrical resistivity of cement paste after 12 h, the silica fume can reduce the electrical resistivity after 24 h. The maximum temperature inside the cement paste gradually decreases with the increase of the content of SAP,and which increases first and then decreases with the increase of silica fume content.