The story of the Hoover Dam is also a great example. It's a massive building project. Big machines were used for excavation, concrete pouring etc. The big story involves the reasons for building the dam, like providing water and electricity. The challenges during construction such as working in a harsh canyon environment, and how the big machines were crucial in getting the job done. It also has a story about the impact on the surrounding area and the people.
The building of the Panama Canal is another big story. There were big machines used for digging through mountains and creating the locks. The big building aspect is the entire canal infrastructure. The story includes the historical reasons for building it, the international cooperation involved, and how the big machines were employed over many years to complete this huge engineering feat.