We delve into the substructure, the crucial support system holding the bridge deck. You'll learn to design piers, the pillars taking the bridge's weight, and abutments providing support at the ends. Analyzing forces acting on these structures and designing them for strength and stability, even during earthquakes, is a key focus. Different pier designs and bearing systems that transfer the bridge's weight to the ground will be explored. Moving underground, you'll tackle foundation engineering - the bridge's cornerstone. We explore different foundation types, from shallow ones for good soil conditions to deep pile foundations for weak soils or heavy bridges. Understanding how soil properties influence the foundation design is crucial. The course equips you to design pile foundations, including selecting the right type, analyzing their load capacity, and ensuring their stability under varying conditions. Well foundations, suitable for deep water or weak soil, will also be covered. But building a bridge isn't just about initial construction. This course emphasizes the importance of monitoring and maintaining bridges throughout their lifespan. You'll learn how engineers use various methods to keep an eye on bridges during construction to identify and address potential issues early on. This includes installing sensors to track the bridge's behavior after construction, allowing for data-driven maintenance decisions. The course covers periodic inspections using visual and specialized techniques to detect problems. You'll learn about routine maintenance tasks like replacing bearings and expansion joints, crucial for ensuring the bridge's long-term functionality. Even bridge widening to accommodate changing traffic needs will be explored. Finally, the course culminates with a fascinating look at bridge construction through real-world case studies. You'll explore how different bridge types are brought to life, from pre-stressed concrete to awe-inspiring cable-stayed bridges. Examining specific construction methods used for each type, such as segmental construction and the impressive balanced cantilever method for achieving large spans, will give you insights into the engineering ingenuity behind these marvels of modern infrastructure. By completing this course, you'll gain a comprehensive understanding of the unseen but critical world that supports bridges. This knowledge is valuable for a career in bridge engineering, construction, or any field where understanding foundations and construction methods is important.