structural performance of repaired corroded reinforced concrete beams
تأليف: mohammed shehada el-ebweini(اعداد):: mohammed ziara(مشرف)
النشر: gaza strip:author 2009
النوع: رسائل جامعية
عدد الصفحات: 95
المواضيع: concrete – materials (construction) – structural engineering:: الخرسانة – الهندسة المدنية
رقم التصنيف: 624.1834
العنوان : structural performance of repaired corroded reinforced concrete beams
العنوان بالعربية : الأداء الإنشائي لعوارض الخرسانة المسلحة المتآكلة التي تم إصلاحها
This research presents the results of a laboratory investigation of the flexuralcapacity such as strength, deflection and steel mechanical properties for both corrodedand repaired corroded beams.
Examination of the behavior of crack development wasalso examined.Fourteen small scaled reinforced concrete beams were used in the testingprogram.
Ten out of them were tested as simply supported beams subjected to twoconcentrated point loads.
Two out of the ten as control beams two others as corrodedbeams and six of them as repaired beams. The other four were used to investigate thecorrosion rate and the mechanicals properties for corroded steel bars.
An electrochemical system was used to achieve the corrosion level. Thespecimens were immersed in a 5 percent of sodium chloride solution for a period of 11weeks.
The beams were connected in parallel to +5 Volts with a capacity of 25 Ampereselectric DC current generated by power supply which impressed an equal voltage oneach beam to accelerate the corrosion process.
Steel bars were immersed in the solutionto act as a cathode and to force the steel reinforced concrete beam to act as an anode.Six corroded beams out of the fourteen were structurally repaired after beencorroded.
Additional longitudinal steel reinforcement bars fixed with shear connectorswere added to the flexural corroded reinforcement.
Three types of cementitious andresin repairing materials were used to apply a new layer instead of the crasheddeteriorated beams bottom concrete cover.It was concluded that the flexural capacity of the corroded beams reduced byabout 28 % compared with the control beams and showed a noted reduction in itsductility behavior during the flexural test.
The flexural capacity of the repaired beamsincreased by about 47 % compared with the control beams.
They showed good ductilitybehavior during the flexural test and performed as sound constructed beams regardingtheir flexural capacity, crack development and deflection.
It also concluded that types of repairing materials used for applying a new layerto corroded beams did not affect the flexural performance of repaired beams, in spite ofthat it may be important to inhabit the corrosion process in the future.