Static Analysis of Reinforced Concrete Pipe Strengthened with GFRP Laminates
This paper presents a study of reinforced concrete pipe with the application of continuous glass fiber reinforced polymer sheet (GFRP). The pipe material is considered to be composed of reinforced concrete and the pipe is strengthen by using glass fiber reinforced polymer sheet. The reinforced concrete pipe is analyzed with different layers of externally applied GFRP sheet. Analysis is carried out in commercially available ANSYS software. A finite element model is developed for the pipe wherein the material properties as mentioned are used. The solid 186 layered structural solid element has been used for discretization of the model. Two sets of GFRP sheets (4 layer & 8 Layer) were considered for the analysis. Results obtained were compared with the controlled pipe made up of reinforced concrete. Results are presented for simply supported boundary conditions for the pipe. The deformation and stress distribution across the pipe has also been analyzed
STRENGTHENING OF CONCRETE COLUMNS WITH CFRP
The use of fiber reinforced polymer (FRP) materials for structural repair and strengthening has continuously increased in recent years, due to several advantages associated with these composites when compared to conventional materials like steel. This paper presents the results of an experiment at study on the structural behavior of reinforced concrete columns strengthened with carbon fiber sheets and strips in pre-cut grooves. The reinforced columns were strengthened before testing. The main tasks of these experiments were conducted to investigate the effects of additional strengthening of reinforced columns.
External Reinforcement of Concrete Beams Using Fiber Reinforced Plastics
A series of 16 under-reinforced beams was tested to study the effectiveness of external strengthening using fiber reinforced plastic (FRP) plates. Plates of glass, carbon and aramid fibers were bonded to the tension side of the beams using a 2-part epoxy. An interative analytical method was developed to predict the stiffness and maximum strength in bending of the plated beam. Increases in stiffness (over the working load range) from 17 to 99 percent and increases in strength (ultimate) from 40 to 97% were achieved for the beams with FRP plates. Predicted and acutal load-deflection curves showed fairly good agreement, although generally the theoretical curves were stiffer. Experimental failure did not occur in the maximum moment region on many of the beams, despite attempts at end anchorages to postpone local shear failure. The ulltimate loads of the beams that did fail in the maximum region were within about 5% of predicted values.