Durability Study on Concrete Bridge Decks with Pultruded FRP Stay-in-place Structural Forms PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Durability Study on Concrete Bridge Decks with Pultruded FRP Stay-in-place Structural Forms PDF full book. Access full book title Durability Study on Concrete Bridge Decks with Pultruded FRP Stay-in-place Structural Forms by Queen's University (Kingston, Ont.). Department of Civil Engineering. Download full books in PDF and EPUB format.
Author: Queen's University (Kingston, Ont.). Department of Civil Engineering
Publisher:
ISBN:
Category :
Languages : en
Pages : 200
Get Book Here
Book Description
This study consists of three phases examining the durability of concrete bridge decks with stay-in-place GFRP structural forms that completely replace the bottom reinforcing bars. Phase I examines the effect of aggressive freeze-thaw (FT) cycles on strength of small scale decks. The concern has been whether entrapped moisture may cause 'frost-jacking' of the form. Eleven specimens were built, each using two spliced flat GFRP plates with T-shape ribs, spanning the gap between girders. The study simulated various surface treatments of the form as well as unbonded and bonded lap splices. The decks were cracked before being saturated and subjected to up to 300 FT cycles at +5°C to -18°C core temperatures. Some specimens were thawed without being submerged and one specimen had perforated forms for drainage. Subsequent testing to failure showed no reduction in ultimate capacity or stiffness, despite the 23% reduction in tensile strength of GFRP coupons from the same form, because failure was governed by punching shear. Phase II compares the GFRP form tested in Phase I to another corrugated form, using short one way slabs to trigger a shear-bond failure. Nine slabs with different surface treatments were fabricated and some were exposed to the same FT cycles. It was clearly shown that flat-ribbed forms are superior to corrugated ones, as no loss in strength occurred after FT exposure, whereas corrugated form-specimens lost 18-21%. This is attributed to the anchorage advantage provided by the T-shape rib embedment in concrete. In Phase III accelerated aging of the two GFRP forms is studied in 3% salt solution at 23, 40 and 55oC for up to 224 days, using 170 coupons to establish tensile strength retentions. Data were assessed using Analysis of Variance (ANOVA). It was shown that the tensile strength retentions of both forms were similar and reduced from 77 to 63% as the temperature increased from 23 to 55°C. Results also showed that the polymer matrix is not fully degraded by the hydrolysis as no significant changes occurred in glass transition temperature. When data was fitted in the Arrhenius service life model, it showed that after 100 years, the ribbed form will suffer more deterioration than the corrugated one as the strength retentions at a location with annual mean temperatures of 10oC were 42 and 61%, respectively.
Author: Queen's University (Kingston, Ont.). Department of Civil Engineering
Publisher:
ISBN:
Category :
Languages : en
Pages : 200
Get Book Here
Book Description
This study consists of three phases examining the durability of concrete bridge decks with stay-in-place GFRP structural forms that completely replace the bottom reinforcing bars. Phase I examines the effect of aggressive freeze-thaw (FT) cycles on strength of small scale decks. The concern has been whether entrapped moisture may cause 'frost-jacking' of the form. Eleven specimens were built, each using two spliced flat GFRP plates with T-shape ribs, spanning the gap between girders. The study simulated various surface treatments of the form as well as unbonded and bonded lap splices. The decks were cracked before being saturated and subjected to up to 300 FT cycles at +5°C to -18°C core temperatures. Some specimens were thawed without being submerged and one specimen had perforated forms for drainage. Subsequent testing to failure showed no reduction in ultimate capacity or stiffness, despite the 23% reduction in tensile strength of GFRP coupons from the same form, because failure was governed by punching shear. Phase II compares the GFRP form tested in Phase I to another corrugated form, using short one way slabs to trigger a shear-bond failure. Nine slabs with different surface treatments were fabricated and some were exposed to the same FT cycles. It was clearly shown that flat-ribbed forms are superior to corrugated ones, as no loss in strength occurred after FT exposure, whereas corrugated form-specimens lost 18-21%. This is attributed to the anchorage advantage provided by the T-shape rib embedment in concrete. In Phase III accelerated aging of the two GFRP forms is studied in 3% salt solution at 23, 40 and 55oC for up to 224 days, using 170 coupons to establish tensile strength retentions. Data were assessed using Analysis of Variance (ANOVA). It was shown that the tensile strength retentions of both forms were similar and reduced from 77 to 63% as the temperature increased from 23 to 55°C. Results also showed that the polymer matrix is not fully degraded by the hydrolysis as no significant changes occurred in glass transition temperature. When data was fitted in the Arrhenius service life model, it showed that after 100 years, the ribbed form will suffer more deterioration than the corrugated one as the strength retentions at a location with annual mean temperatures of 10oC were 42 and 61%, respectively.
Author: RAOUF. BOLES
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 166
Get Book Here
Book Description
Wide-flanged concrete girders are increasingly being used for highway bridges in Wisconsin. The objective of this research was to understand the state of the art of non-metallic SIP forms and to develop design guidelines and performance specifications that can be used locally for the construction of highway bridge decks. Four major types of stay-in-place (SIP) forms using fiber reinforced concrete (FRC) or fiber reinforced polymer (FRP) materials were investigated: fiber reinforcements, grid reinforcements, bar reinforcements and pultruded profiles. The results were used to develop a model design and construction specification for non-structural, non-metallic, SIP forms in highway bridge decks.
Author: Thomas D. Larson
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 174
Get Book Here
Book Description
Author: David Allan Dieter
Publisher:
ISBN:
Category :
Languages : en
Pages : 464
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 154
Get Book Here
Book Description
Author: Anna Beth Pridmore
Publisher:
ISBN:
Category :
Languages : en
Pages : 379
Get Book Here
Book Description
The deterioration of steel in aging reinforced concrete bridges is a continual problem which could benefit from improved rehabilitation techniques that take advantage of enhanced and more durable materials such as fiber reinforced polymer (FRP) composites. Appropriately designed hybrid material systems benefit from the performance and durability advantages of FRP materials yet remain more cost effective than comparable all-composite systems. Development of rapid rehabilitation systems for the decks of concrete box girder bridges, which are increasingly common throughout the United States, is presented. One goal of this research is to assess and validate the use of FRP composite panels for use as both stay-in-place formwork and as the bottom longitudinal and transverse reinforcement in the deck of concrete box girder bridges. Performance assessments for full-scale two-cell box girder bridge specimens through monotonic and extensive cyclic loading provided validation for the FRP panel system bridge deck as a viable rehabilitation solution for box girder bridge decks. The FRP panel system performed comparably to a conventionally reinforced concrete bridge deck in terms of serviceability, deflection profiles, and system level structural interaction and performed superior to the RC bridge deck in terms of residual deflections, and structural response under cyclic loading. Assessment of a damaged FRP panel bridge deck system, which was repaired using a resin injection technique, showed superior performance for the repaired system in terms of integrity of the FRP panel interface and cyclic response. Rapid rehabilitation techniques for strengthening reinforced concrete box girder bridge deck overhangs using near-surface-mounted (NSM) carbon fiber reinforced polymer (CFRP) were also evaluated. Analytical predictions of load carrying capacity and deflections provided correlation with experimental results, and the developed analysis methods provide an effective design tool for future research. Results from the laboratory testing of a bridge deck overhang strengthened with FRP showed significant increases in load carrying capacity as well as deformation capacity as compared to the as-built specimen without FRP. This research provides enhanced understanding of hybrid structures and indicates significant potential for rehabilitation applications to concrete box girder bridges.
Author: Adam C. Berg
Publisher:
ISBN:
Category :
Languages : en
Pages : 584
Get Book Here
Book Description
Author: David A. Jacobson
Publisher:
ISBN:
Category :
Languages : en
Pages : 426
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 301
Get Book Here
Book Description
It is a major challenge to build bridge systems that have long-term durability and low maintenance requirements. A solution to this challenge may be to use new materials or to implement new structural systems. Fiber reinforced polymer (FRP) composites have continued to play an important role in solving some of persistent problems in infrastructure applications because of its high specific strength, light weight, and durability. Structural engineers always have valued the combination of materials into a hybrid structural system that takes advantage of the properties inherent in each of its constituents. In this study, the concept of the hybrid FRP-concrete structural systems is applied to both bridge superstructure and deck systems. The hybrid FRP-concrete bridge superstructure and deck systems are intended to have durable, structurally sound, and cost effective hybrid system that will take full advantage of the inherent properties of both FRP materials and concrete. The hybrid-FRP deck system can be installed in new construction, or can be attached to existing deck substructure after removing deteriorated concrete deck. In this study, two hybrid FRP-concrete bridge systems were investigated. The first system consists of trapezoidal cell units forming either a bridge superstructure or a bridge deck unit. The second one is formed by arch cells. The two systems rely on using cellular components to form the core of the deck system, and an outer shell to warp around those cells to form the integral unit of the bridge. Both systems were investigated analytically by using finite element (FE) analysis. From the rigorous FE studies, it was concluded that first system is more efficient than the second. Therefore, the first hybrid FRP-concrete system had been used to investigate the feasibility of the FRP-concrete structural systems in the remainder of the study. The proposed system consists of trapezoidal FRP cell units surrounded by an FRP outer shell forming a bridge system. A thin layer of concrete was placed in the compression zone. Concrete was confined by GFRP laminates which provide protection from environmental exposure. Moreover, the concrete layers reduce the local deformation of the top surface of the bridge under concentrated loads. Webs of the box section were designed at an incline to reduce shear force between sections. For the experimental phase of the study, a prototype bridge superstructure was designed as a simply-supported single span one-lane bridge with a span length of 18.3 m. Geometrical parameters of the proposed bridge system were determined by detailed finite element analyses. FEA was used to verify the structural behavior of this hybrid bridge superstructure prior to embarking on manufacturing and testing. Performance of this hybrid bridge superstructure was examined both experimentally and computationally. A test specimen, fabricated as a one-fourth scale model of the prototype bridge, was subjected to a series of loading tests: nondestructive tests (flexure, off-axis flexure, and negative flexure), and destructive tests (flexure and shear). Also, as a trial case for FRP-concrete bridge deck supported on steel girders, a prototype bridge system was designed as a simply supported steel bridge with a hybrid FRP-concrete deck. Details for connecting the hybrid decks with steel girders were investigated both experimentally and computationally. A test specimen, fabricated as a 3/4 scale model of the prototype bridge, was evaluated by series of service flexural loading tests under different loading conditions. Moreover, the composite action between the hybrid deck and steel girders was analyzed and tested. The effective flange width in the hybrid FRP-concrete deck acting compositely with the steel girders was evaluated at service conditions. Three different constitutive models for GFRP composites were integrated in the finite element analysis to examine the inelastic behavior and to predict failure of both the hybrid bridge deck and superstructure. Results from the both experimental and computational analysis for both the hybrid bridge superstructure and deck systems confirmed that the hybrid FRP-concrete bridge systems have an excellent performance from structural engineering point of view. The experimental results showed robust performance where cracking in the exterior GFRP laminates, interface failure, and slippage between GFRP and concrete under AASHTO design loads for the hybrid bridge superstructure were not exhibited. Also, both test specimens satisfied the AASHTO live load deflection limit. In addition, the shear connections at girder-deck interface of the deck specimen on steel girders demonstrated an excellent performance under service load. Furthermore, it was observed that the hybrid deck and the steel girders are interacting as a partially composite system under service-load conditions. The effective flange width for hybrid decks are less than AASHTO prescribed effective width for reinforced concrete decks. It was shown that a detailed finite element analysis could predict behavior of the test specimens under different loading conditions up to the failure point.
