摘要: |
This project will produce a report that provides practical engineering guidance for the replacement of deficient bridges with low-water stream crossings in the rural Midwest. The report will address the following issues: (1) site assessment and economics; (2) selection of crossing type -- the two basic types of low-cost low-water crossings are the unvented ford and the vented ford; (3) design of roadway profile and culvert pipes; (4) selection of crossing materials -- low-water crossings can be built of concrete, crushed stone, natural stone, stone reinforced with geogrid or geotextile, stone-filled gabions and other materials; and (5) general design details. The project will provide guidelines for materials selection, provide general design details for unvented fords and vented fords constructed of different materials, and also provide guidance on signage of low-water crossings. |