"1-85 Bridge AssignmentDr. Owalabi briefly discussed the 1-85 collapse that happened in the metro Atlanta area back inMarch. Please response to the questions regarding that incident below:Q1. Why did it Collapse?Q2. What type of structure is this?Q3. What type of foundation of stone and gravel in Atlanta, Georgia?Q4. What was the engineering cause of the collapse?Q5. Suggest mitigative measures?th Ans. 1 On, March 30 , 2017 a bridge, 1-85 in Atlanta collapsed, during the rush hour, because ofthe massive fire underneath viaduct. The fire was viciously set by a group of 3 people. GeorgiaDepartment of Transportation had stored construction material under the bridge, which wereseveral tons of coiled plastic piping which ignited and fueled the fire. The heat from the fireraised the temperature and caused the 100 foot 1-85 northbound bridge to collapse. Ans. 2 This was a reinforced concrete interstate Bridge structure, which is popular as 1-85,passes over the Piedmont Road and crosses the center of the city. Also, it merges with anotherhighway 1-75, along the route for almost 7.5 miles, which is called as Downtown Connector. Ans. 3 In North of Georgia, gravels are generally variable in size, color, ranging from shades ofgrey to dark grey and are composed of Granite. Bank sands are common mostly consist of quartzand light in colour. Sand is 70-80% in concentration in the pavement of Atlanta, Georgia.Ans 4 During the construction of the bridge, steel is put inside the concrete for reinforcement.The strength of the steel and also concrete can get reduced by the extreme level of heat. In thecase of 1-85 massive fire raised the level of the heat so high that it reduced the strength of theconcrete reinforcement bridge, which got collapsed.Ans. 5 Mitigative Measures include:-? The destructed part of bridge should get replaced by strong, improved and competentquality concrete material and steel bars, so as to improve the worst condition of thebridge after collapse.? Leaks and spills near project area from the equipments used for construction and vehiclesshould be taken into daily inspection account.? By calming the active traffic, using street diversions, conditions in and around the area 1- 85 can be improved for the time being till the construction gets over. "