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外文翻譯--一個良好的公路的基礎-公路隧道(編輯修改稿)

2025-06-26 08:21 本頁面
 

【文章內容簡介】 ut they will allow you to plan for traffic 河南理工大學 09 級交通工程專業(yè)外文翻譯 2020 4 loadings through a road’s life. 6. Design for maintenance Without maintenance a road will rapidly deteriorate and fail. Design your roads so they can be easily maintained. This means: ? adequate ditches that can be cleaned regularly ? culverts that are marked for easy locating in the spring ? enough space for snow after it is plowed off the road ? proper cross slopes for safety, maintenance and to avoid snow drifts ? roadsides that are planted or treated to prevent erosion ? roadsides that can be mowed safely A rule of thumb for adequate road width is to make it wide enough for a snowplow to pass another vehicle without leaving the travelled way. Mark culverts with a post so they can be located easily. 7. Pave only when ready It is not necessary to pave all your roads immediately. There is nothing wrong with a wellbuilt and wellmaintained gravel road if traffic loads and volume do not require a paved surface. Three hundred vehicles per day is the remended minimum to justify paving. Don’t assume that laying down asphalt will fix a gravel road that is failing. Before you pave, make sure you have an adequate crushed stone base that drains well and is properly pacted. The remended minimum depth of crushed stone base is 10 depending on subgrade soils. A road paved only when it is ready will far outperform one that is constructed too quickly. 8. 202。 Build from the bottom up This mandment may seem obvious, but it means that you shouldn’t top dress or resurface a road if the problem is in an underlying layer. Before you do any road improvement, locate the cause of any surface problems. Choose an improvement technique that will address the problem. This may mean recycling or removing all road materials down to the native soil and rebuilding everything. Doing any work that doesn’t solve the problem is a waste of money and effort. 9. 202。 Protect your investment The road system can be your municipality’s biggest investment. Just as a home needs painting or a new roof, a road must be maintained. Wisconsin’s severe climate requires more road maintenance than in milder places. Do these important maintenance activities: Surface — grade, shape, patch, seal cracks, control dust, remove snow and ice Drainage — clean and repair ditches and culverts。 remove all excess material Roadside — cut brush, trim trees and roadside plantings, control erosion Traffic service — clean and repair or replace signs Design roads with adequate ditches so they can be maintained with a motor grader. Clean and grade ditches to maintain proper pitch and peak efficiency. After grading, remove all excess material from the shoulder. 10. Keep good records Your maintenance will be more efficient with good records. Knowing the road’s construction, life, and repair history makes it much easier to plan and budget its future repairs. Records can also help you evaluate the effectiveness of the repair methods and materials you used. Good record keeping starts with an inventory of the system. It should include the history and surface condition of the roadway, identify and ev
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