《电力水利 外文文献 文献翻译 英文文献 涵洞设计》由会员分享，可在线阅读，更多相关《电力水利 外文文献 文献翻译 英文文献 涵洞设计（12页珍藏版）》请在金锄头文库上搜索。
1、Culvert Design1Introduction： Culverts have been utilized for thousands of years as a means to transmit water under walkways or roads. Often, a culvert is simply installed without much thought to how much water it needs to convey under extreme conditions. If a culvert cannot convey all of the incomin
2、g water, then the water will flow over or around the pipe, or simply back up behind the culvert creating a pond or reservoir. If any of these conditions are unacceptable, then the proper culvert diameter and number of culverts must be selected prior to installation in order to convey all of the anti
3、cipated water through the pipe(s). This calculation helps the designer size culverts as well as present a headwater depth vs. discharge rating curve.The LMNO Engineering calculation is primarily based on the methodology presented in Hydraulic Design of Highway Culverts by Normann (1985) and publishe
4、d by the U.S. Department of Transportations Federal Highway Administration. It is also known as HDS-5 (Hydraulic Design Series No. 5). HDS-5 focuses on culvert design. Culvert design is usually based on the maximum acceptable discharge - thus the HDS-5 methodology is geared toward culverts flowing f
5、ull with water possibly flowing over the road above the culvert. In addition to programming the HDS-5 methodology, LMNO Engineering wished to compute headwater depths for lesser flows. Therefore, in addition to the HDS-5 methodology, we have added the Manning equation for culverts flowing partially
6、full. The HDS-5 methodology also assumes that the user knows the tailwater depth (Yt) before using the methodology. Though Yt can be found by field measurements, it is often computed in the office using Mannings equation based on bottom width, side slopes, channel roughness, and channel slope. There
7、fore, LMNO Engineering added the additional feature of a built-in subroutine for computing Yt for trapezoidal channels. Note that for the graphing portion of our calculation, Yt is re-computed for the entire range of flows (Qt) shown on the graph (unless the user specifically inputs Yt).1摘自：科技报告缩微资料
8、库涵洞和水工结构作者：wellen 凯恩 dl;费尔班克斯斯特- 阿拉斯加大学Design Culvert And Design Requirements for Culvert JointsThe Culvert command lets you model the behaviour of a culvert under various conditions of flow. A culvert is a short, closed (covered) conduit that conveys stormwater runoff under anembankment, usually a
9、roadway. The primary purpose of a culvert is to convey surface water, butproperly designed it may also be used to restrict flow and reduce downstream peak flows. Inaddition to the hydraulic function, a culvert must also support the embankment and/or roadway,and protect traffic and adjacent property
10、owners from flood hazards to the extent practicable.Most culvert design is empirical and relies on nomographs and standard procedures. The purposeof this section is to provide an overview of culvert design standards and procedures.Because of the many variables involved, the process is largely one of
11、 trial and error and MIDUSS does not suggest initial feasible values for the design.Culvert design can be carried out for either steady, (i.e. time invariant) flow or for an inflow hydrograph. When inflow is in the form of a hydrograph the hydraulic design can be followed by a routing process that s
12、hows the attenuation of the inflow hydrograph caused by ponding that occurs upstream of the embankment. In such cases the peak outflow from the barrel will be less than the peak inflow and you can refine the barrel design for the reduced flow if desired. The design of a culvert should take into acco
13、unt many different engineering and technical aspectsat the culvert site and adjacent areas. The list below presents the key considerations for thedesign of culverts.25-year design storm event.The allowable headwater is the depth of water that can be ponded at the upstream end of theculvert during th
14、e 100 yr event with clogged conditions, which will be limited by one or more ofthe following constraints or conditions.(1) The allowable headwater must not damage upstream property.(2) The ponding depth is to be no greater than the low point in the road grade.(3) The ponding depth is to be no greate
15、r than the elevation where flow diverts around the ulvert.(4) Headwater elevations shall be established to delineate potential flood zones.Your Culvert design can be preceded by a Channel design with either a trapezoidal or complex cross-section. When this is done the cross-sectional shape of the ch
16、annel is inherited by the culvert design and used to describe the flow cross-section upstream of the culvert. If the inflow is a flow hydrograph, a channel design may be followed by a Channel routing process from which the channel outflow forms the inflow to the culvert.The culvert is assumed to be located below a sag point in a highway embankment that will form an overflow weir in the event that the barrel flow capacity is sufficiently surcharged. Flow separation betw
