Factors Affecting Strength of Elements Designed Using Strut-and-Tie Models. Paper by Sergio F. Breña and Micah C. Morrison/Discussion by Emil de Souza Sánchez Filho, Júlio J. Holtz Silva Filho, and Maria Teresa Gomes Barbosa

The authors statement, "The strength of the nodes, struts, and ties was calculated using procedures in Appendix A of the 2002 ACI Code (ACI Committee 318 2002)" is very unclear because this strength depends on the quite a lot of parameters and this code provides several expressions to calculate the concrete effectiveness factor. 2. All three possible different D regions are cataloged in Jennewein and Schäfer (1992), where the expressions for forces, angles of the struts, and ties are given for each D region, and it is a waste of time trying to compare with another special truss model for D regions near the openings, which is the case of models of Specimens 2A and 2B.