Complete and translate the following sentences. 1. The loads on bridge components may be subdivided into the permanent load involving (собственный вес пролетных строений
1. The loads on bridge components may be subdivided into the permanent load involving (собственный вес пролетных строений, опор, фундаментов), the active load by the wind force, ice, breaking force, seismic activity, (перепад температур) and the moving load from the rolling stock and (пешеходы) .
2. Like other structures, bridges must sustain (собственный вес и временная нагрузка). (Постоянные нагрузки) consist of the self-weight of the bridge itself as well as the loads from bridge railings, sidewalks, lighting facilities, etc. which the bridge must support.
3. Planners estimate the dead weight with a high degree of accuracy during (проектирование) and accurately control it during (строительство). The moving load is important for successful (расчет конструкций) and planning of any bridge.
4. Live loads include vertical and horizontal impact forces created by (транспортные средства) and pedestrians passing the bridge as well as forces resulting from (ветер, землетрясение) and temperature variation. Other moving loads are secondary in nature and result from impact forces, for instance, (навал судов).
5. The most difficult problem for the live load calculation is the preliminary determination of (невыгодное положение) of the rolling stock and pedestrians. The planner cannot estimate the live loads to be imposed upon the bridge as precisely as the dead loads because it often has little, if any, control over these loads once the bridge is put into operation.
6. (Размыв грунта) can have destructive effects on bridges. (Насыпи и опоры) can reduce the rivers natural width, and the speed of the water flow increases.
7. (Надежный пропуск транспорта и воды) during the high water period is one of the problems for maintenance crews because of washout.
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