Mike11 ---07---过河桥梁模拟基本设置

发布于新浪博客，时间：2009-02-19 21:49:55 原文 (opens new window)

过河桥梁模拟

桥的阻水问题比较复杂，水头损失来自于桥的底坎（类似于堰）、进水流线收缩、出水流线扩展等，用Energy Loss方法无法合理模拟。可将桥梁概化为一个箱涵（如果桥面过水还可再加一个堰），应用MIKE 11中的箱涵（＋堰）设置来计算。

Energy Loss 用于计算河道突然缩窄/展开、急弯、缓弯等造成的局部水头损失。选用Energy Loss后模型采用的计算公式见MIKE 11 Users Manual （P.121），相应的水头损失系数取值可根据你要模拟的情况在所有标准水力学教科书上都有介绍。---摘自DHI总工Dr.Zhang

模拟方法的选择：

自由流体方法 pure free flow methods

桥墩 For peirs

• Bridge piers (Nagler)

The pier shape is taken into account through a so-called coefficient of discharge which is found through a table based on the pier type. The equation is derived from free flow experiments and is not accurate for high velocities.

b The total bridge opening width exclu** the piers.

• Bridge Piers (Yarnell)

The equation assumes free flow. Thus if submergence and possible overtopping is to be modelled an alternative method should be used.

拱桥 For Arches

Arch bridges (Biery and Delleur)

Arch bridges (Hydraulic research method, HR)

桥孔淹没流与溢桥流 combined with submergence/overflow methods

Energy Equation

Federal Highway Administration (FHWA) WSPRO method

US Bureau of Public Roads (USBPR) method

Overflow is only available in combination with submerged flow. When the bridge structure bottom level is exceeded the bridge type solution will be ignored and replaced with a submerged solution. When the bridge structure top level is exceeded the submerged solution is combined with overflow.

Also note that the use of the two bridge types Fully submerged bridge and Bridge piers  D'Aubuisson's formula) requires the installation of a separate module.

Overview****组左侧为设置的桥梁个数，右侧为每一桥梁对应的开口设置

Overview: Left part shows River name, Chainage and Bridge ID. Right part show methods for the bridge openings.

右侧桥梁下面开口设置时，删除第一行，然后设置相应参数保存。如出现Access violation...错误提示或看似设置了桥墩并计算成功但结果里查看并没有设置桥梁的效果，此问题还是出在这，设置的桥墩参数并没有保存。此bug在其他结构物参数设置如此类表格式界面的都存在这个问题。