考虑压实质量影响的碾压混凝土坝层间结合质量动态评价研究

碾压混凝土坝的层间结合质量评价是碾压混凝土坝施工质量控制的重要手段。已有的研究仅考虑层面处理和层间间隔时间对层间结合质量的影响,不仅忽略了压实质量对碾压混凝土坝层间结合质量的影响,而且未能够对大坝层间结合质量进行动态评价。本研究提出实时监控下考虑压实度及其不确定性影响的碾压混凝土坝层间结合质量动态评价模型,模型的建立主要包括3个方面的内容:(1)基于熵-盲数理论对混凝土特性参数进行处理,提出考虑参数不确定性影响的压实度动态计算方法,并将压实度计算结果应用于层间结合质量评价;(2)以混凝土初凝时间与层间间隔时间的差值作为评价指标,解决不同季节条件下评价模型的适用性问题;(3)建立了3个层次的碾压混凝土坝层间结合质量评价指标体系,并基于线性回归分析方法建立了层间结合质量与层间间隔时间、压实度的映射关系。结合实际工程,应用基于实时监控系统建立的评价模型对某碾压混凝土坝的层间结合质量进行了动态评价;结果表明本研究不仅能够在准确评价层间结合质量的同时提供参数不确定性影响等信息,而且层间结合质量动态评价结果更符合实际。

Dynamic evaluation of RCC dam Interlayer bonding quality considering the influence of compaction quality

Evaluation of the interlayer bonding quality is the key way for controlling the roller compacted concrete dam (RCC dam) construction. The existing study only considered the influences of layer process-ing and the interval time, which ignored the influence of the compaction quality on the interlayer bonding quality. Besides, there is no dynamic evaluation study of the interlayer bonding quality. In this study, an interlayer bonding quality dynamic evaluation model considering the influence of the compaction quality and its uncertainties based on the real-time monitoring system is proposed and the model contains three main contents:(1) processing the concrete characteristic parameters based on the entropy-blind number theory, and the compaction degree dynamic calculation method considering the uncertainties of the parameters is proposed. The compaction degree calculation results will be used in the interlayer bonding quality evalua-tion;(2) the deference value between the concrete initial setting time and the interval time is calculated as the evaluation factor, which solves the feasibility problem of the model in different seasons; and (3) a three level evaluation factors system is built, and the mapping relationship between the interlayer bonding quality and the interval time and the compaction degree is established. Combining the practical engineer-ing, the interlayer bonding quality of an RCC dam is evaluated dynamically using the model based in the real time monitoring system. The evaluation results proved that the study model can evaluate the interlayer bonding quality and provide more information including the parameter uncertainty. The dynamic evaluation model of interlayer bonding quality can give more practical results.