Generally all engineering is ?interdisciplinary? to some extent. By its nature, Construction Engineering crosses the discipline boundaries on a regular basis. Construction projects can range from demolition, to reclamation and on to new construction, so it requires a very broad knowledge base.
The start of a new project is often the end of an old one. For example, a bridge replacement project begins with the removal of the existing structure and requires that the construction engineer understand explosive application and safety, material properties and structural behavior.
Construction of a new bridge then requires construction engineers to use their knowledge of surveying, excavation, concrete placement, steel erection, and rigging & hoisting. Construction efforts can be very dangerous places with many crafts operating in a congested area. The construction engineer must understand safe construction practices as well as being able to analyze new or unusual methods.