基于回归分析的长距离水工隧洞泵送混凝土抗压强度研究

Analysis of the Compressive Strength of Long Distance Pumping Concrete for Hydraulic Tunnels based on Regression Analysis

以龙开口电站一期工程长距离泵送C25混凝土为对象,研究不同泵送距离、不同水灰比、不同粉煤灰掺量等对混凝土强度的影响。在相同的条件下养护7d,根据实测混凝土的28d抗压强度,通过回归分析,建立了不同距离泵送C25混凝土标准抗压强度公式。实测的混凝土强度与试配强度相差无几,证明适量掺粉煤灰不影响其抗压强度。并得出长距离泵送混凝土粉煤灰掺量宜控制在10%~30%之间。

Based on the C25 pumping concrete used in the first phase project of Longkaikou Hydropower Station, the influences of the pumping distance, water cement ratio and fly ash content on the compressive strength of concrete are analyzed. The 28-day compressive strengths of the concrete specimens after 7-day curing are measured. A standard compressive strength equation is established using the regression analysis for the C25 pumping concrete under different pumping distances. The measured concrete strength is of little difference with the prescribed value. It demonstrated that proper amount of fly ash does not affect the compressive strength. Also, it shows that the dosage of fly ash for long distance pumping concrete should be controlled between 10% and 30%.