Week4

Week 4

            The group accomplished a lot during last week’s lab.  During the first part of the lab each member worked in modifying their designs to optimize the strength to cost ratio.   After modifying each design the group came together to analyze and make a final pick on a bridge design.   The design that was picked had a cost of 260 thousand dollars initially but one of the group members realized that the price cost could be decreased even more.  No changes were made regarding the structure of the bridge; instead changing the building materials reduced the cost of the bridge.  Initially the bridge only used solid bars with the standard 140x140 thickness.  After a lot of modification the cost of the bridge was brought down to $241, 389.46.   

            West Point bridge design is a really good simulation for building a Knex bridge.  Although WPBD is a realistic representation o a real bridge, I wouldn’t recommend it to be used for building a real bridge.  The main problem with this program is that only considers the force of gravity and weight load.  A really important force that WPBD is not considering is the force of wind.  Wind is really important force that should be considered when designing and building a bridge.  If this force is not considered when designing a bridge, it would be very likely that the bridge would eventually collapse.  Also this program doesn’t consider other facts such resistance to natural disasters such as earthquakes and weather conditions.  Although I don’t recommend this program for building a real bridge, I think that it suits perfectly for this lab.