Ensayos a rotura de vigas de hormigón con pretensado exterior. Segunda parte: Vigas continuas

Up ta failure tests on externally prestressed concrete beams: Second part: Continuous beams

In this article two up to failure tests on one externally prestressed concrete twospan continuous beam are presented. For the first test, the prestressing tendons were anchored only on the extreme diaphragm. And for the second test the new tendons were blocked at the one central support diaphragm, reducing their length to half the tendon length of the first test. Due to this length reduction and in spite of the damage of the beam from the first test, the ultimate load capacity in the second test was higher than in the first one. The increment of prestressing steel stress from the effective stress up to failure were, in both cases, remarkables. These increments of stress and other parameters measured during the test were compared with those obtained from a numerical analysis, showing excellent correlation.