Abstracts Book - IMRC 2018

• SE4-O030
LOAD CAPACITY DEGRADATION OF CORRODED PRESTRESSED
CONCRETE ELEMENTS
Arturo Zalapa 1 , Ramon A. Figueroa Carranza 1 , Andres Antonio Torres Acosta 2 , Wilfrido Martinez
Molina 3 , Elia Mercedes Alonso Guzman 1
1 Universidad Michoacana de San Nicolás de Hidalgo, Materials Laboratory, Mexico. 2 Instituto
Mexicano del Transporte, CIVIE, Mexico. 3 Universidad Michoacana de San Nicolás de Hidalgo, ,
Mexico.
Durability of concrete structures is affected by environment hazzards like
chlorides in marine environment. This work shows the results of a corrosion
accelerated program performed to prestressed concrete by appliying a galvanic
current to the prestressed strands. The evaluated beams had four embedded
prestressed steel rods on the beam´s bottom (anode) and one prestressed
rod at top (cathode). NaCl contamination (1% by cement mass) in the concrete
was added to the middle third of each prestressed beam, in order to accelerate
corrosion in that area. Further acceleration of the corrosion process was
achieved by applying a nominal 65 μA/cm2 constant anodic current. Other
group of prestressed beams was fabricated, which were not subjected to the
process of accelerated corrosion, and accted as control beams. Corrosion crack
survey (crack length and width measurements) was performed before and after
the galvanic current was applied. The results show a significant increase in the
occurrence of longitudinal cracks in the direction of prestressing steel. When
achieving the target corrosion degradation, beams were disconnected and
flexure tests were performed (three point bend tests). Results shown that a
decrease of the 48.3% of beam´s load capacity was achieved when only 15% of
radius loss due to corrosion was obtained.
Keywords: Accelerated corrosion, Load capacity, Prestressed beams
Presenting authors email: andres.torres@umq.maristas.edu.mx