International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 10, October 2013) 261 Rehabilitation and Strengthening of R.C.C. STRUCTURES by using FRP composites Rahul kumar satbhaiya 1 , Shishir gupta 2 , T.R Arora 3 1 M.Tech Scholar CTM, LNCT Bhopal (M. P.) 2 Asst Proff LNCT Bhopal (M.P.) 3 H.O.D Department Of Civil Engg. LNCT Bhopal (M.P.) Abstract— Fiber Reinforced Polymer (FRP) as an external reinforcement is used extensively to deal with the strength requirements related to flexure and shear in structural systems. But the strengthening of members subjected to torsion is explored only recently. Torsion failure is an undesirable brittle form of failure which should be avoided specially in the earthquake prone areas. In the present work, the behaviour and performance of rectangular reinforced concrete beams strengthened with externally bonded Fibre Reinforced Polymer (FRP) fabrics subjected to combined flexure and torsion is studied experimentally. Three sets of concrete cylinders were tested for their ultimate strengths. In SET I three concrete cylinders (F1, F2 and F3) are tested. In SET II three concrete cylinders (S1, S2 and S3) are tested. In SET III three concrete cylinders (R1, R2 and R3) are tested. The concrete cylinders F1, S1 and C1 were taken as the control concrete cylinders. It was observed that the concrete cylinders F1, S1 and C1 had less load carrying capacity when compared to that of the externally strengthened beams using FRP sheets. In SET I concrete cylinders F2 is strengthened only single warp of FRP sheet on the full dimensions of concrete cylinders and F3 is strengthened by double warp of FRP sheet on the full dimensions of concrete cylinders. In SET II concrete cylinders S2 is strengthened only single warp of FRP sheet on the full dimensions of concrete cylinders and S3 is strengthened by double warp of FRP sheet on the full dimensions of concrete cylinders. In SET III concrete cylinders R2 is strengthened only single warp of FRP sheet on the full dimensions of concrete cylinders and R3 is strengthened by double warp of FRP sheet on the full dimensions of concrete cylinders. The ultimate load carrying capacities of all the concrete cylinders are calculated. Experimental data on ultimate cracking loads of each of the cylinders were obtained. The effect of different types and configuration of FRP and ultimate load carrying capacity of the cylinders were investigated. Keywords— Concrete, Cylinder, Failure, Fibre, Polymer, Reinforced I. INTRODUCTION This The maintenance, rehabilitation and upgrading of structural members, is perhaps one of the most crucial problems in civil engineering applications. Moreover, a large number of structures constructed in the past using the older design codes in different parts of the world are structurally unsafe according to the new design codes. Since replacement of such deficient elements of structures incurs a huge amount of public money and time, strengthening has become the acceptable way of improving their load carrying capacity and extending their service lives. Infrastructure decay caused by premature deterioration of buildings and structures has lead to the investigation of several processes for repairing or strengthening purposes. One of the challenges in strengthening of concrete structures is selection of a strengthening method that will enhance the strength and serviceability of the structure while addressing limitations such as constructability, building operations, and budget. Previously, the retrofitting of reinforced concrete structures, such as columns, beams and other structural elements, was done by removing and replacing the low quality or damaged concrete or/and steel reinforcements with new and stronger material. However, with the introduction of new advanced composite materials such as fiber reinforced polymer (FRP) composites, concrete members can now be easily and effectively strengthened using externally bonded FRP composites. Retrofitting of concrete structures with wrapping FRP sheets provide a more economical and technically superior alternative to the traditional techniques in many situations because it offers high strength, low weight, corrosion resistance, high fatigue resistance, easy and rapid installation and minimal change in structural geometry. In addition, FRP manufacturing offers a unique opportunity for the development of shapes and forms that would be difficult or impossible with the conventional steel materials. Although the fibers and resins used in FRP systems are relatively expensive compared with traditional strengthening materials, labour and equipment costs to install FRP systems are often lower. FRP systems can also be used in areas with limited access where traditional techniques would be impractical.
13
Embed
Rehabilitation and Strengthening of R.C.C. STRUCTURES - IJETAE
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
International Journal of Emerging Technology and Advanced Engineering
Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 3, Issue 10, October 2013)
261
Rehabilitation and Strengthening of R.C.C. STRUCTURES by
using FRP composites
Rahul kumar satbhaiya1, Shishir gupta
2, T.R Arora
3
1M.Tech Scholar CTM, LNCT Bhopal (M. P.)
2Asst Proff LNCT Bhopal (M.P.)
3H.O.D Department Of Civil Engg. LNCT Bhopal (M.P.)
Abstract— Fiber Reinforced Polymer (FRP) as an external
reinforcement is used extensively to deal with the strength
requirements related to flexure and shear in structural
systems. But the strengthening of members subjected to
torsion is explored only recently. Torsion failure is an
undesirable brittle form of failure which should be avoided
specially in the earthquake prone areas. In the present work,
the behaviour and performance of rectangular reinforced
concrete beams strengthened with externally bonded Fibre
Reinforced Polymer (FRP) fabrics subjected to combined
flexure and torsion is studied experimentally.
Three sets of concrete cylinders were tested for their
ultimate strengths. In SET I three concrete cylinders (F1, F2
and F3) are tested. In SET II three concrete cylinders (S1, S2
and S3) are tested. In SET III three concrete cylinders (R1, R2
and R3) are tested. The concrete cylinders F1, S1 and C1 were
taken as the control concrete cylinders. It was observed that
the concrete cylinders F1, S1 and C1 had less load carrying
capacity when compared to that of the externally
strengthened beams using FRP sheets. In SET I concrete
cylinders F2 is strengthened only single warp of FRP sheet on
the full dimensions of concrete cylinders and F3 is
strengthened by double warp of FRP sheet on the full
dimensions of concrete cylinders. In SET II concrete
cylinders S2 is strengthened only single warp of FRP sheet on
the full dimensions of concrete cylinders and S3 is
strengthened by double warp of FRP sheet on the full
dimensions of concrete cylinders. In SET III concrete
cylinders R2 is strengthened only single warp of FRP sheet on
the full dimensions of concrete cylinders and R3 is
strengthened by double warp of FRP sheet on the full
dimensions of concrete cylinders. The ultimate load carrying
capacities of all the concrete cylinders are calculated.
Experimental data on ultimate cracking loads of each of
the cylinders were obtained. The effect of different types and
configuration of FRP and ultimate load carrying capacity of