Wall selection is an iterative process that involves cycles of preliminary design and
cost estimation. The first and most important step is to define the design problem with
design objectives and constraints. The objective of almost all design problems is least
cost, although there will be many cases, particularly in urban areas, where objectives
will include aesthetic and environmental considerations as well. Costs such as those
for materials and construction are much easier to quantify than are aesthetic and environmental
costs. In the latter instances, it is sometimes difficult to verify which one of
the feasible solutions is the best. In order to find solutions that are at least feasible,
constraints such as serviceability requirements (wall horizontal movement, vertical
differential settlement, etc.) and spatial limitations (rights-of-way, underground easements,
etc.) should be defined as comprehensively as possible. Designs (wall types)
that meet the prescribed constraints are all feasible solutions. A ranking of these feasible
solutions (wall types) is required. The ranking should include spatial behavior and
economic factors as discussed later in this article. Ideally, the wall with the highest
rank should be adopted for detailed design; the rest can be used as design alternatives or
discarded if the selected wall is confidently lowest cost, or is the only wall that satisfies
all the established design requirements.
Wall selection is an iterative process that involves cycles of preliminary design andcost estimation. The first and most important step is to define the design problem withdesign objectives and constraints. The objective of almost all design problems is leastcost, although there will be many cases, particularly in urban areas, where objectiveswill include aesthetic and environmental considerations as well. Costs such as thosefor materials and construction are much easier to quantify than are aesthetic and environmentalcosts. In the latter instances, it is sometimes difficult to verify which one ofthe feasible solutions is the best. In order to find solutions that are at least feasible,constraints such as serviceability requirements (wall horizontal movement, verticaldifferential settlement, etc.) and spatial limitations (rights-of-way, underground easements,etc.) should be defined as comprehensively as possible. Designs (wall types)that meet the prescribed constraints are all feasible solutions. A ranking of these feasiblesolutions (wall types) is required. The ranking should include spatial behavior andeconomic factors as discussed later in this article. Ideally, the wall with the highestrank should be adopted for detailed design; the rest can be used as design alternatives ordiscarded if the selected wall is confidently lowest cost, or is the only wall that satisfiesall the established design requirements.
การแปล กรุณารอสักครู่..
