ABSTRACT
This chapter covers the strength of the different elements of the strut-and-tie model (STM), struts, nodes (or nodal zones), and ties. For the concrete struts, the behavior of concrete under different loading conditions and the different basic compression stress fields, prismatic, bottle-shaped, and fan-shaped, are discussed. The geometry and strength of nodes (nodal zones) under different boundary conditions are explained. The strength of reinforced ties and the influence of their detailing on the geometry of the connecting nodal zones are examined. The chapter also presents the nominal strength and design strength of struts, nodal zones, and ties according to the ACI 318-14 provisions. Finally, this chapter covers the reinforcement anchorage with regard to bond action of straight bars, anchorage length, lap joints, and curved reinforcement.
