رسائل ماجيستير
English
2017
Behavior of Reinforced Concrete Columns Buried into Different Types of Aggressive Soils
زهراء فاضل حنش, شاكر أحمد صالح, ليث شاكر رشيد
كلية الهندسة-جامعة كربلاء · العراق
Concrete resistance to sulfate attack is one of the most important properties for maintaining durability of concrete. The main objective of thisresearch is to evaluate the performance of several types of reinforced concrete columns buried in two pits at a 3-meter depthin one of the agricultural areas in the holy city of Kerbala, one containsa sandy soil with sulfur salts (SO3=10.609%) and the other containsa clayeysoil with salinity ratioof(SO3= 2.61%).In this research, three types of concrete mixes have beenproduced and utilized: normal strength concrete, polymeric concrete, and high strength concrete. A total of 21 reinforced concrete columns, 126 concrete cubes, and 63 concrete cylinders were prepared. The columns and reference concrete specimenswere cured for 28 days with tap water and then buried in soils for (60, 150, 240) days. A number oflaboratory testing methodshave beencarried out on the specimens: (axial compression strengthof concrete columns, compressive strengthtest for concrete cubes, splittingtensile strength of concrete cylinders, absorption test, voids ratioand density of concrete cubes). These tests have beenconducted at differentages of exposure.Testresults showed that the aggressive soils (containing sulfates and chlorides) affect the performance of all types of concrete mixes negatively with age of exposure. The deterioration was more for specimen buried in sandy soils. It is found that the resistance of high-strength concrete to aggressive soils was better than other types of concrete.The percentage ofdecreasein compressive strength of concrete columns exposed to aggressive solutions in the clayey soil for normal, polymer, and high-strength concretesranged from (0.95-12.51)%, (20.28-24.96) %,and (1.5-15.62) % respectively. The percentage of decreasein compressive strength capacity of polymer,and high-strength concrete columns exposed to aggressivesolutions in Abstract
VIIthe sandy soils ranged between (20.03-37.52) %, and (0-18.74) % respectively, compared to the reference concrete columns not buried in soils.In contrast a development in strength was observed for normal concrete columns exposed to aggressive sandy soils, it reads up to (11.7 %) after (240 days) of exposure. The durability test results (absorption and voids ratio) showed a deterioration (increases) for polymer and high strength concrete mixes, while it was not observed in normal concrete mix.