6678

6229

كارشناسي ارشد

سازه

اصفهان: دانشگاه صنعتي اصفهان، دانشكده عمران

1390

يازده، 118ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

داود مستوفي نژاد

محمدرضا افتخار

17/2/91

علي اكبر مقصودي، مرتضي مدح خوان

1396/10/06

كتابنامه

عمران

مهندسي عمران

ID6229

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

Effect of Grooving Method Instead of Conventional Surface Preparationon Flexural Failure Mechanism of Concrete Beams Strengthened with FRP Amir reza Moghaddas Bidabadi a moghaddas@cv iut ac ir September 21 2011 Department of Civil Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Dr Davood Mostofinejad Assoc Prof Email address dmostofi@cc iut ac irAdviser Dr Mohamadreza Eftekhar Assistan Prof Email address eft@cc iut ac ir Abstract Retrofitting of reinforced concrete and steel structures due to reasons such as drawbacks in old codes changing the usage of structure destructive environmental factors and deficiencies in construction process isfrom important issues in structural engineering Strengthening of structures with FRP composites is one of themethods that have been welcomed by researchers due to the unique properties of FRPs including their hightensile strength light weight simple application and resistance to corrosive environment Although the mainpurpose of retrofitting is to increase the overall load carrying capacity of the structures however the failuremechanism of the strengthened member is also very important In a reinforced concrete beam four modes of flexural failure mechanism is possible a concrete crushing aftersteel yields b concrete crushing before steel yields c FRP rupture after steel yields and d FRP rupture beforesteel yields To achieve any of these modes premature surface deboning should be controlled and prevented Debonding of FRP sheets from concrete substrate is directly affected by the method of connecting FRPlaminates to the concrete i e the conventional surface preparation and the new method of grooving in the formof externally bonded reinforcement on grooves EBROG has been recently introduced in the literature Toexamine the effects of the aforementioned methods 36 reinforced concrete beam specimens with the dimensionsof 120 140 1000 mm were cast and strengthened with FRP laminates and subjected to four point flexuralloading Then the flexural failure mechanisms of the beams were investigated using both EBROG andconventional EBR methods 6 concrete beam specimens with the dimensions of 100 100 500 mm with 4reinforced concrete beam with the dimensions of 120 140 1000 mm were tested to control the effect ofdelaying between different steps in EBROG method Numerical investigation on experimental samples from thispaper and other scientific sources has been done The results indicate EBROG is more effective than EBR to control debonding and increasing load carryingcapacity of beams in all four flexural failure mechanisms Putting delay between steps of EBROG methodreduces the efficiency of it ACI 440 2R 08 code does not have sufficient accuracy in predicting load carryingcapacity and failure mechanism of beams strengthened with FRP Key Words FRP EBR EBROG Debonding Flexural Failure Mechanism

داود مستوفي نژاد

محمدرضا افتخار

علي اكبر مقصودي، مرتضي مدح خوان