All of the prestressed concrete members so far considered have been statically determinate. This reflects the major use of prestressed concrete in building structures, since the most common type of prestressed concrete construction is in the form of simply supported beams. However, there are important applications of prestressed concrete in statically indeterminate structures. Many of the features of the analysis and design of these structures are similar to those used for statically determinate structures, as outlined in previous chapters. There are two important differences, however: the introduction of secondary moments and the behaviour at the ultimate limit state. These will be discussed in the following sections.