This document develops a methodology that evaluates the impact on the environment of the rivers produced by the creation of civil infrastructures. The methodology is based on the two-dimensional hydrodynamic calculation by using shallow water equations both in the conditions prior to the creation of the infrastructure, and in the new conditions after the infrastructure is created. Subsequently, several characteristics, such as water depth and velocity, among others, are compared between the initial and final conditions, and a two-dimensional zoning of the changes observed is obtained. The methodology herein presented is useful to verify the impact that the implantation of different infrastructures around the river currents could produce. In addition, it is also relevant for carrying out a study taking into account different infrastructure options related to river currents, as well as for selecting the most suitable one. By using the methodology presented, changes on the regime of the currents caused by the infrastructures can be deduced, including a qualitative and quantitative zoning of the changes, with a special emphasis on some characteristics, such as depth and velocity. The methodology is applied in a case study for the creation of a road bridge over the Jalon River in Spain.

中文翻译：

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二维模型水动力对比分析及在新桥上的应用

本文件开发了一种方法，用于评估创建民用基础设施对河流环境的影响。该方法基于二维水动力计算，通过在基础设施创建之前的条件和基础设施创建之后的新条件中使用浅水方程。随后，在初始条件和最终条件之间比较了几个特征，例如水深和速度等，并获得了观察到的变化的二维分区。本文提出的方法有助于验证在河流周围植入不同基础设施可能产生的影响。此外，考虑到与河流水流相关的不同基础设施选项，以及选择最合适的基础设施选项，这对于开展研究也很重要。通过使用所提出的方法，可以推断出由基础设施引起的水流状态的变化，包括变化的定性和定量分区，特别强调一些特征，例如深度和速度。该方法应用于在西班牙 Jalon 河上建造一座公路桥的案例研究。比如深度和速度。该方法应用于在西班牙 Jalon 河上建造一座公路桥的案例研究。比如深度和速度。该方法应用于在西班牙 Jalon 河上建造一座公路桥的案例研究。