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交通工程專業(yè)外文翻譯外文文獻(xiàn)英文文獻(xiàn)(編輯修改稿)

2024-07-13 23:42 本頁面
 

【文章內(nèi)容簡介】 road, use traffic counts that project numbers and sizes of vehicles 20 years into the future. These are only projections, at best, but they will allow you to plan for traffic loadings through a road’s life.6. Design for maintenanceWithout 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 safelyA 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 readyIt 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 upThis 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 investmentThe 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 iceDrainage — clean and repair ditches and culverts。 remove all excess materialRoadside — cut brush, trim trees and roadside plantings, control erosionTraffic service — clean and repair or replace signsDesign 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 recordsYour maintenance will be more efficient with good records. Knowing the road’s construction, life, and repair history mak
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