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A Structural Balanced Network in Real Life

Aerial photos of the Oakland span of the new Bay Bridge taken“Bay Bridge’s troubled China Connection – How Caltrans’ choice of an inexperienced company left structural doubts and cost taxpayers” by Charles Piller.

In this article, it talks about the major issue Caltrans faced regarding its Bay Bridge project. The San Francisco–Oakland Bay Bridge is a complex of bridges spanning San Francisco Bay in California. A Chinese company Shanghai Zhenhua Port Machinery Co. Ltd, also known as ZPMC, was hired to build the key parts of this Bay Bridge project because of its reputation of fast and cost-effective. The company claims it will be able to save The California Department of Transportation about $250 million dollars and able to finish all its parts in just 5 years. However, as the production of the key parts carried out, the suspension span faced some construction problems, such as “suspect concrete in the tower foundation, broken anchor bolts, rust on the main cable, and cracked roadway welds”.

Regarding the quality control of constructing key parts, there were many parties and engineers involved and each expressed their opinion. This is a real life example of a large network we learned on the first day of class. Each person/company involved represented by a node and the relationship between two people/companies is represented by an edge. Particularly, this is an example of what we have learned in Chapter 4 of Networks, Crowds, and Markets. The key players in Caltrans in this situation can be split into two parties, which are defending welding quality controls and criticizing/voiced the handling of welds. For example, Tony Anziano (Toll Bridge Program Manager in Caltrans) and John Fisher (Professor Emeritus of civil engineering in Lehigh University) defended welding quality controls. On the opposite side, Douglas Coe (Supervising Bridge Engineer) and Gary Pursell (Principal Transportation Engineer) expressed their concerns regarding the safety issue. Chapter 4- Networks in Their Surrounding Contexts suggests that the members of each respective party shares similar characteristics and ideas with each other. In this case, Anziano and Fisher share similar ideas on defending the quality control and thus have positive relationship with each other. On the other hand, they will have hostile relationships with opposing party members, like Coe and Pursell. Overall, this is a structural balanced network.



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