43 research outputs found
Round robin testing initiative for fiber reinforced polymer (FRP) reinforcement
An international Round Robin Testing (RRT) programme on FRP reinforcement was
conducted within the framework of the Marie Curie Research Training Network, ENCORE,
and with the support of Task Group 9.3 of the International Federation for
Structural Concrete (fib). Eleven laboratories and six manufacturers and suppliers
participated in this exercise. As part of this extensive experimental endeavour, one or more
of the following tests were performed by the participating laboratories: 1) tensile tests on
FRP bars and strips; 2) tensile tests on FRP laminates; 3) double bond shear tests on FRP
laminates (Externally Bonded Reinforcement, EBR) and FRP bars/strip (Near Surface
Mounted reinforcement, NSM). This paper will discusses the results of the RRT initiative,
among which the experimental results of bond tests on concrete specimens strengthened
with EBR and NSM FRP
FRP reinforcement in RC structures
fib Bulletin 40 deals mainly with the use of FRP bars as internal reinforcement for concrete structures. The background of the main physical and mechanical properties of FRP reinforcing bars is presented, with special emphasis on durability aspects. For each of the typical ultimate and serviceability limit states, the basic mechanical model is given, followed by different design models according to existing codes or design guidelines
Confined Concrete Columns Stability with Longitudinal CFRP Reinforcement
The stability and strength of concrete columns confined by tangential CFRP wrapping and longitudinal external CFRP sheet is studied. Plain and confined columns of slenderness l = 40 are tested. Two batches of concrete with different ultimate compressive strengths 25 and 50 MPa are investigated. The total number of specimens is 24 (sixteen 300 mm high cylinders for material properties and eight 1500 mm high columns, all specimens with diameter 150 mm). Unconfined and with one and two CFRP sheet layers confined concrete columns are tested. Further longitudinal CFRP sheet in one and two layers are added on the confined columns. The theoretical prediction of ultimate strength and stability of columns coincides rather well with experimental results. It is concluded that additional external strengthening of CFRP confined concrete columns by attaching longitudinal CFRP sheets is efficient. The two methods applied lead to similar results, that the additional longitudinal reinforcement is efficient for improving stability of confined columns in region of moderate slenderness 3
Confined Concrete Columns Stability with Longitudinal CFRP Reinforcement
The stability and strength of concrete columns confined by tangential CFRP wrapping and longitudinal external CFRP sheet is studied. Plain and confined columns of slenderness l = 40 are tested. Two batches of concrete with different ultimate compressive strengths 25 and 50 MPa are investigated. The total number of specimens is 24 (sixteen 300 mm high cylinders for material properties and eight 1500 mm high columns, all specimens with diameter 150 mm). Unconfined and with one and two CFRP sheet layers confined concrete columns are tested. Further longitudinal CFRP sheet in one and two layers are added on the confined columns. The theoretical prediction of ultimate strength and stability of columns coincides rather well with experimental results. It is concluded that additional external strengthening of CFRP confined concrete columns by attaching longitudinal CFRP sheets is efficient. The two methods applied lead to similar results, that the additional longitudinal reinforcement is efficient for improving stability of confined columns in region of moderate slenderness 3
Tests to estimate the cooperation between confined concrete and column reinforcement up to compressive failure
The stability and strength of reinforced concrete columns confined by tangential external CFRP wrapping is studied. The plain and confined columns of slenderness λ = 66.7 and λ = 16 with or without longitudinal steel bar (with diameter 12 mm and 16 mm) reinforcement are tested. Two batches of concrete with different ultimate compressive strength are investigated