Describe the steps that an engineer must follow if asked to determine the need for a grade-separated railroad grade crossing that would replace an at-grade crossing of a two-lane highway with a rail line.
What will be an ideal response?
The first step the engineer will need to follow is to define the situation.
The engineer must fully understand the reason why the grade-separated structure
is said to be needed.
The next step is to define the problem in terms of the objectives to be
accomplished by the project. The objectives for this project might be to improve
safety by reducing or eliminating vehicle-train interaction. Another quantifiable
objective might include the reduction in travel time to the motorists by
eliminating delay due to crossing trains.
The third step for the engineer is to identify solutions to the perceived
problem. Possible solutions to the problem might include the installation of
active warning devices at the grade crossing, the diversion of motorists to other
close-by grade crossings, or to construct a grade separated structure. A “no-build”
or “do-nothing” alternative is typically considered as a possible solution.
The fourth step in the process is to analyze the expected performance of
each of the alternatives under present and future conditions. This analysis should
employ quantified measures of effectiveness such as travel time delay reductions
and crash rate reductions. The analysis should also take into consideration costs
such as the construction, maintenance, and operation costs of each alternative.
The fifth step in the process is to compare the alternatives against the
objectives developed in step 2 of this process. The advantages and disadvantages
of each must be studied.
The sixth step is to recommend one of the alternatives after considering all
of the factors involved.
The final step in the process is to design the facility after one of the
alternatives has been selected. This step also moves the project out of the planning
process and into project development.
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