地震作用下大型渡槽结构输水功能可靠性分析

大型钢筋混凝土渡槽作为生命线类水工结构，其输水功能可靠性至关重要。然而，一方面混凝土材料的力学性能表现出显著的随机性与非线性特征，另一方面渡槽结构在服役期内可能遭受不确定的灾害性地震作用，对渡槽结构的服役安全带来威胁。为此，采用混凝土随机损伤力学模型量化混凝土随机性与非线性耦联下渡槽结构的动力响应，并基于概率密度演化理论给出了渡槽结构输水功能可靠性分析方法。以某实际大型钢筋混凝土渡槽结构为例，详述了渡槽结构输水功能可靠性分析的原理和实现流程。研究表明，概率密度演化理论可以准确高效地对渡槽结构输水功能可靠性进行评估；不同设计水准下渡槽结构的输水功能可靠性指标存在一定的差异，在设计初期应予以合理考虑。

Water-conveyance functional reliability analysis of large-scale aqueduct structures subjected to earthquake excitations

Large scale reinforced concrete aqueduct, as a lifeline hydraulic structure, the reliability of its water transport function is very important. However, on one hand, the mechanical property of concrete is equipped with remarkable randomness and nonlinearity. On the other hand, the aqueduct structures may inevitably suffer from uncertain disastrous earthquake actions during service life, posing a great threat to their service safety. To these ends, the present paper proposed a quantification framework for the water-conveyance reliability assessment of the aqueduct structures by incorporating the stochastic damage mechanics model of concrete and the probability density evolution method. The principle and implementation procedures of the developed framework were illustrated in detail on an actual large-scale RC aqueduct structure. The results show that the probability density evolution theory can accurately and efficiently evaluate the reliability of aqueduct structure water conveyance function. The water-conveyance reliability varies with the change of pre-defined seismic fortifications, which should be reasonably accounted for in early design phases.