土石坝压实质量连续检测指标影响因素分析

Influencing factors of continuous testing indices of earth-rock dam compaction quality

为了提高土石坝碾压中连续压实控制技术的适用性,设计并开展了3项现场试验,研究了振动碾压时的激振力、行进速度引起的连续检测指标CMV、CCV、K s和VCV的测值偏差,采用线性回归分析方法研究了强、弱振工艺对不同类别连续检测指标相关性校验的影响规律,并分析了连续检测指标测值与碾压遍数之间的相关性,进而给出了土石坝连续压实检测的应用建议。研究结果表明:激振力引起各类连续检测指标测值的偏差约为50%~80%,速度引起的偏差小于15%。激振力对压实度计类指标的相关性校验影响显著,且在弱振工况下各类连续检测指标得到的决定系数更高。VCV和K s指标与碾压遍数之间具有强相关性,能够更好地适用于碾压工艺法和测值增量法。

In order to improve the applicability of continuous compaction control technique,three field tests were designed and carried out for the granite residual soil filler of an earth-rock dam.The measurement deviations of the continuous testing indices of CMV,CCV,K s and VCV caused by the exciting force and travel speed of the vibration rolling were studied.Then,the influence of strong and weak vibration techniques on the correlation calibration of different types of continuous testing indices was discussed and the correlation between the measurement value of the continuous testing indices and the number of the rolling passes was analyzed using linear regression analysis method.Finally,practical suggestions on the engineering application of continuous compaction control technique for earth-rock dams were put forward.The research results show that the deviation of various continuous testing indices caused by the exciting force is in the range of 50%to 80%,and the deviation caused by speed is less than 15%.The exciting force has a significant influence on the correlation verification of the compactness gauge indices,and the coefficient of determination obtained by various continuous testing indices in the weak vibration mode is higher.There is a strong correlation between the number of rolling passes and the indices of VCV and K s,so these two indices can be better applied to the compaction technique and incremental measurement method.