This lecture covers the concept of partial connection in composite beams, where the degree of connection is limited for beams with a span of 5 to 10 m. Topics include flexible connectors, plastic calculation, and the ultimate resistance of composite beams. The instructor explains the principles of partial connection, the number of connectors required, and the limitations in deflections due to interface sliding. Additionally, the lecture delves into the particularities of composite slabs, such as reinforcements, end anchors, and the mixed effect of profiled sheet-concrete. The session concludes with discussions on resistance factors, concrete cracking effects, and the calculation of internal forces in composite structures.