Please answer me these $"$ bridge and tunnel construction course $"$ assignment question" breifly?

$1.$ When do we need to construct bridges?

$2.$ Bridge is said to be a key element in any transportation system because it determines the capacity of the system. How can a bridge determine the capacity of a highway or railway?

$3.$ What are the economic and social benefits of bridge construction?

$4.$ What are the objectives in bridge design? How do we attain each of the objectives

$5.$ Why should a bridge engineer worry about safety and aesthetics in his design? Give general guidelines that if followed would result in a bridge of improved appearance.

$6.$ Give the design philosophy of AASHTO $2005$ used in bridge design. What is each limit state concerned with?

$7.$ Bridge Engineer is said to be a planner, architect, designer, constructor, and facility manager. What is the significance of each of this aspects of role of a bridge engineer?

$8.$ Give account of the history of development of bridge construction during the past $200$ years. Give the aesthetic development of bridges also during the past $200$ years.

$9.$ What is the purpose of investigation for bridges? Outline the steps in investigation from preliminary up to detailed data collection and give the purpose or goal of each.

$10.$ What information should be gathered during field visit that will help the bridge engineer to identify the preferred location for the bridge and decide on the type, size and capacity of the bridge?

$11.$ What data are gathered during investigation? List the criteria used to select the best bridge site. Does the alignment of the road affect bridge site selection in any way?

$12.$ After site selection, give factors affecting span selection. How do these factors affect span selection?

$13.$ How do you estimate design flood level for design? What are the factors significantly affecting design discharge? When do you use HWM$?$ How do you determine HWM$?$

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$14.$ What are the factors affecting selection of the size of free board?

$15.$ What are the contents of investigation report for a major bridge? What will the team carrying out the investigation composed of$?$