Études des mécanismes d'érosion du roc à l'aval des évacuateurs de crues par des simulations expérimentales à grande échelle

水电大坝一般配备在岩石中开挖的溢洪道。一个严重的问题是，流水造成的侵蚀会到达大坝的直接基础。在一些hydro - quamesbec水坝遗址观察到这种侵蚀的情况，但迄今没有造成严重后果。hydro - qubec对侵蚀预测方法非常感兴趣，以确保其工程的可持续性。现有的一些确定这些工程侵蚀状态的方法是基于经验反馈的。这些方法在世界上几个新的大坝实例上的应用表明，这些方法所观测到的侵蚀与预测结果之间存在着很大的差距。它们的经验性质使得很难确定该方法不能产生正确预测的条件；特别是，研究几种地质力学参数对侵蚀的综合影响是不可能的。该项目的目标是开发一种更适合岩体条件的侵蚀预测新方法。首先，有必要确定哪些地质力学参数对侵蚀程度影响最大，并确定每个参数在侵蚀过程中的相对重要性。为此，作为该项目的一部分，将设置两个仪表疏散器，第一个用于实验室规模，第二个用于现场试点工厂规模。该设备将使实验研究岩体的几个地质力学参数的影响以及每个参数在侵蚀过程中的相对重要性成为可能。实验测试结果和观测到的侵蚀数据库将用于校准数值模型，以确定地质力学参数对实际侵蚀的影响。这些研究的最终结果将导致一个预测岩石溢洪道岩体侵蚀性的新模型的发展。

Hydroelectric dams are generally equipped with spillways excavated in rock. A serious concern is that erosion caused by flowing water reaches the immediate dam foundation. Cases of such erosion, with no serious consequences to date, have been observed at the site of some Hydro-Québec dams. Hydro-Québec is very interested in methods for the prediction of erosion, in order to ensure the sustainability of its works. Some existing methods to determine the state of erosion of these works are based on experience feedback. The application of these methods on several new dam cases in the world have shown significant gap between the observed erosion and the forecasts obtained by these methods. Their empirical nature makes it difficult to identify conditions for which the method does not yield a correct prediction; In particular, it is impossible to study the combined effects of several geomechanical parameters on the erosion.The objective of this project is to develop a new approach to erosion prediction better adapted to rock mass conditions. First of all, it is necessary to identify which geomechanical parameters have the greatest impact on the erosion level and to determine the relative importance of each of the parameters in the erosion process. For this, two instrumented evacuators, the first one at the laboratory scale, the second one, at a field Pilot-Plant scale, will be set up as part of this project. This equipment will make it possible to study experimentally the effects of several geomechanical parameters of the rock mass and the relative importance of each parameter in the erosion process. Experimental test results and the observed erosion database will be used to calibrate numerical models to determine the effects of geomechanical parameters on erosion on a real scale. The final results of these studies will lead to the development of a new model for predicting rock mass erodability at rock spillways.