Precast Prestressed Concrete Panel Subdecks in Skewed Bridges 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 Precast Prestressed Concrete Panel Subdecks in Skewed Bridges PDF full book. Access full book title Precast Prestressed Concrete Panel Subdecks in Skewed Bridges by Robert E. Abendroth. Download full books in PDF and EPUB format.
Author: Robert E. Abendroth
Publisher:
ISBN:
Category :
Languages : en
Pages : 74
Get Book Here
Book Description
Precast prestressed concrete panels have been used in bridge deck construction in Iowa and many other states. To investigate the performance of these panels at abutment or pier diaphragm locations for bridges with various skew angles, a research program involving both analytical and experimental aspects, is being conducted. This interim report presents the status of the research with respect to four tasks. Task 1 which involves a literature review and two surveys is essentially complete. Task 2 which involved field investigations of three Iowa bridges containing precast panel subdecks has been completed. Based on the findings of these investigations, future inspections are recommended to evaluate potential panel deterioration due to possible corrosion of the prestressed strands. Task 3 is the experimental program which has been established to monitor the behavior of five configurations of full scale composite deck slabs. Three dimensional test and instrumentation frameworks have been constructed to load and monitor the slab specimens. The first slab configuration representing an interior panel condition is being tested and preliminary results are presented for one of these tests in this interim report. Task 4 involves the analytical investigation of the experimental specimens. Finite element methods are being applied to analytically predict the behavior of the test specimens. The first slab configuration representing an interior panel condition is being tested and preliminary results are presented for one of these tests in this interim report. Task 4 involves the analytical investigation of the experimental specimens. Finite element methods are being applied to analytically predict the behavior of the test specimens. The first test configuration of the interior panel condition has been analyzed for the same loads used in the laboratory, and the results are presented herein. Very good correlation between the analytical and experimental results has occurred.
Author: Robert E. Abendroth
Publisher:
ISBN:
Category :
Languages : en
Pages : 74
Get Book Here
Book Description
Precast prestressed concrete panels have been used in bridge deck construction in Iowa and many other states. To investigate the performance of these panels at abutment or pier diaphragm locations for bridges with various skew angles, a research program involving both analytical and experimental aspects, is being conducted. This interim report presents the status of the research with respect to four tasks. Task 1 which involves a literature review and two surveys is essentially complete. Task 2 which involved field investigations of three Iowa bridges containing precast panel subdecks has been completed. Based on the findings of these investigations, future inspections are recommended to evaluate potential panel deterioration due to possible corrosion of the prestressed strands. Task 3 is the experimental program which has been established to monitor the behavior of five configurations of full scale composite deck slabs. Three dimensional test and instrumentation frameworks have been constructed to load and monitor the slab specimens. The first slab configuration representing an interior panel condition is being tested and preliminary results are presented for one of these tests in this interim report. Task 4 involves the analytical investigation of the experimental specimens. Finite element methods are being applied to analytically predict the behavior of the test specimens. The first slab configuration representing an interior panel condition is being tested and preliminary results are presented for one of these tests in this interim report. Task 4 involves the analytical investigation of the experimental specimens. Finite element methods are being applied to analytically predict the behavior of the test specimens. The first test configuration of the interior panel condition has been analyzed for the same loads used in the laboratory, and the results are presented herein. Very good correlation between the analytical and experimental results has occurred.
Author: R.E. Abendroth
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages : 218
Get Book Here
Book Description
Precast prestressed concrete panels have been used as subdecks in bridge construction in Iowa and other states. To investigate the performance of these types of composite slabs at locations adjacent to abutment and pier diaphragms in skewed bridges, a research project which involved surveys of design agencies and precast producers, field inspections of existing bridges, analytical studies, and experimental testing was conducted. The survey results from the design agencies and panel producers showed that standardization of precast panel construction would be desirable, that additional inspections at the precast plant and at the bridge site would be beneficial, and that some form of economical study should be undertaken to determine actual cost savings associated with composite slab construction. Three bridges in Hardin County, Iowa were inspected to observe general geometric relationships, construction details, and to note the visual condition of the bridges. Hairline cracks beneath several of the prestressing strands in many of the precast panels were observed, and a slight discoloration of the concrete was seen beneath most of the strands. Also, some rust staining was visible at isolated locations on several panels. Based on the findings of these inspections, future inspections are recommended to monitor the condition of these and other bridges constructed with precast panel subdecks. Five full-scale composite slab specimens were constructed in the Structural Engineering Laboratory at Iowa State University. One specimen modeled bridge deck conditions which are not adjacent to abutment or pier diaphragms, and the other four specimens represented the geometric conditions which occur for skewed diaphragms of 0, 15, 30, and 40 degrees. The specimens were subjected to wheel loads of service and factored level magnitudes at many locations on the slab surface and to concentrated loads which produced failure of the composite slab. The measured slab deflections and bending strains at both service and factored load levels compared reasonably well with the results predicted by simplified Finite element analyses of the specimens. To analytically evaluate the nominal strength for a composite slab specimen, yield-line and punching shear theories were applied. Yield-line limit loads were computed using the crack patterns generated during an ultimate strength test. In most cases, these analyses indicated that the failure mode was not flexural. Since the punching shear limit loads in most instances were close to the failure loads, and since the failure surfaces immediately adjacent to the wheel load footprint appeared to be a truncated prism shape, the probable failure mode for all of the specimens was punching shear. The development lengths for the prestressing strands in the rectangular and trapezoidal shaped panels was qualitatively investigated by monitoring strand slippage at the ends of selected prestressing strands. The initial strand transfer length was established experimentally by monitoring concrete strains during strand detensioning, and this length was verified analytically by a finite element analysis. Even though the computed strand embedment lengths in the panels were not sufficient to fully develop the ultimate strand stress, sufficient stab strength existed. Composite behavior for the slab specimens was evaluated by monitoring slippage between a panel and the topping slab and by computation of the difference in the flexural strains between the top of the precast panel and the underside of the topping slab at various locations. Prior to the failure of a composite slab specimen, a localized loss of composite behavior was detected. The static load strength performance of the composite slab specimens significantly exceeded the design load requirements. Even with skew angles of up to 40 degrees, the nominal strength of the slabs did not appear to be affected when the ultimate strength test load was positioned on the portion of each slab containing the trapezoidal-shaped panel. At service and factored level loads, the joint between precast panels did not appear to influence the load distribution along the length of the specimens. Based on the static load strength of the composite slab specimens, the continued use of precast panels as subdecks in bridge deck construction is recommended.
Author: Kristen Shawn Donnelly
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 242
Get Book Here
Book Description
Following development of rectangular prestressed, precast concrete panels (PCP) that could be used as stay-in-place formwork adjacent to expansion joints in bridge decks, the Texas Department of Transportation (TxDOT) initiated a research effort to investigate the use of PCP units at skewed expansion joints. The fabrication of trapezoidal PCP units was studied and the response of skewed panels with 45° and 30° skew angles was obtained. The panels were topped with a 4 in. thick cast-in-place (CIP) slab to complete the bridge deck. Specimens with 45° skew performed well under service and overload levels. The deck failed in diagonal shear at loads well over the design level loads. However, two 30° specimens failed prematurely by delamination between the topping slab and the PCP. The cause of the delamination was insufficient shear transfer capacity between the PCP and CIP topping slab. For the specimens tested at a square end, the failure mode was punching shear at high loads for all specimens. The surface condition of the PCP was specified to have a "broom finish" and the panel was to have a saturated surface dry (SSD) condition so that PCP units would not leach moisture from the CIP topping slab. Neither of these conditions was satisfied in the two panels that failed prematurely. Although the panels were specified to have a broom finish, the panel surface had regions that were quite smooth. The objective of this research project was to reinvestigate the response of 30° PCP at an expansion joint following specified procedures for finish and moisture conditions. One specimen was constructed with a rectangular panel placed between two 30° skewed panels. These panels had a much rougher surface texture than the previously tested panels that failed in delamination. The skewed ends of the specimen were subjected to monotonically increasing static loads at midspan of the panel ends. The panels failed in diagonal shear and the response of the tested specimen confirmed that the panel surface roughness, and not the skew angle, caused delamination with the previously tested specimens. While TxDOT does not currently specify a minimum panel surface roughness, a surface roughness of approximately 1/4 in. is required in some codes for developing composite action. In addition, wetting the panels to a SSD condition prior to placement of the topping slab further enhances shear transfer between the topping slab and the PCP.
Author: Marvin Henry Hilton
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 17
Get Book Here
Book Description
The results of prior research conducted on precast prestressed panel subdecks for use in the construction of bridge decks are reviewed and summarized. This construction technique utilizes the precast panel subdecks as the forming for the cast-in-place upper portion of the deck. After placement of the upper portion of the deck the panels become an integral part of the deck thickness. The placement and removal of wooden type formwork are thus eliminated and the construction time and safety hazards normally experienced during form removal are thereby reduced. The field experience and research results to date indicate the technique to be reliable. Some hairline cracking can be expected to occur on the cast-in-place deck directly above the joints between prestressed panels. Cores from the bridge decks show that the cracking does not penetrate the full depth of the upper slab and is not considered detrimental to the structural integrity of the deck. It was recommended that Virginia adopt the innovation on a trial basis to gain experience with the technique.
Author: Mohsen A. Issa
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 278
Get Book Here
Book Description
A literature review concerning the objectives of the project was completed. A significant number of published papers, reports, etc., were examined to determine the effectiveness of full depth precast panels for bridge deck replacement. A detailed description of the experimental methodology was developed which includes design and fabrication of the panels and assembly of the bridge. The design and construction process was carried out in cooperation with the project Technical Review Panel. The major components of the bridge deck system were investigated. This includes the transverse joints and the different materials within the joint as well as composite action. The materials investigated within the joint were polymer concrete, non-shrink grout, and set-45 for the transverse joint. The transverse joints were subjected to direct shear tests, direct tension tests, and flexure tests. These tests exhibited the excellent behavior of the system in terms of strength and failure modes. Shear key tests were also conducted. The shear connection study focused on investigating the composite behavior of the system based on varying the number of shear studs within a respective pocket as well as varying the number of pockets within a respective panel. The results indicated that this shear connection is extremely efficient in rendering the system under full composite action. Finite element analysis was conducted to determine the behavior of the shear connection prior to initiation of the actual full scale tests. In addition, finite element analysis was also performed with respect to the transverse joint tests in an effort to determine the behavior of the joints prior to actual testing. The most significant phase of the project was testing a full-scale model. The bridge was assembled in accordance with the procedures developed as part of the study on full-depth precast panels and the results obtained through this research. The system proved its effectiveness in withstanding the applied loading that exceeded eight times the truck loading in addition to the maximum negative and positive moment application. Only hairline cracking was observed in the deck at the maximum applied load. Of most significance was the fact that full composite action was achieved between the precast panels and the steel supporting system, and the exceptional performance of the transverse joint between adjacent panels.
Author: Parul Patel
Publisher:
ISBN:
Category :
Languages : en
Pages : 382
Get Book Here
Book Description
Author: Marvin Henry Hilton
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 13
Get Book Here
Book Description
This final report is a supplement to an earlier report that covered the installation of the first precast, prestressed panel subdecks installed on a bridge in Virginia. The report discusses the inspection of the decks one year after they were completed and the relative ease of construction using the precast subdeck technique as opposed to permanent steel forms and conventional timber forming. Estimates of the relative costs between the three types of forming and consideration of the speed of construction suggest that the precast subdeck technique can reduce superstructure costs and save time and labor during construction. The original bridge design incorporated epoxy-coated reinforcing steel in the cast-in-place upper portion of the decks. This provision was made to protect the reinforcing steel against the intrusion of chlorides since the deck was expected to crack over some of the joints between the subdeck panels. Hairline cracking was observed on some of the decks above the joints between the subdeck-panels. There was no definite pattern to the cracking in some of the other spans, but this may have been due to lack of traffic loading on all but one lane of the twin bridges at the time of the final inspection. While similar cracking is often found in conventionally constructed decks, the joints between the subdeck panels appear to control the location of cracking that might otherwise occur at random locations. It was recommended that the precast subdeck panels technique be considered as a viable alternative for use in the design and construction of bridge decks.
Author: Iowa. Department of Transportation
Publisher:
ISBN:
Category : Transportation
Languages : en
Pages : 120
Get Book Here
Book Description
Author: Lesley Sneed
Publisher:
ISBN:
Category : Bridges
Languages : en
Pages :
Get Book Here
Book Description
"This research has examined spalling of several partial-depth precast prestressed concrete (PPC) bridge decks. It was recently observed that some bridges with this panel system in the MoDOT inventory have experienced rusting of embedded steel reinforcement and concrete spalling issues in the deck panels. The objectives of this research were to investigate the causes of spalling in precast-prestressed panels and propose cost-effective alternative solutions including improved design options for new construction, as well as suggest mitigation methods for existing deteriorated bridge decks. A survey of transportation agencies and a series of bridge deck investigations were conducted to determine the nature and causes of spalling. Panel deck system modifications were proposed and evaluated for potential use in new construction. These modifications were investigated in terms of structural performance and serviceability with respect to the current design. Panel deck system modifications evaluated included an increase in tendon side cover, the addition of fibers or corrosion inhibitor to the panel concrete mixture, an increase in reinforcement in the cast-in-place concrete topping, and the substitution of edge tendons with epoxy-coated steel or carbon fiber reinforced polymer tendons. Efficiency of the proposed solutions was examined and validated through fundamental laboratory studies and numerical simulations using finite element modeling. Finally, recommendations are provided for new and existing construction to mitigate the spalling problem"--Technical report documentation page.
Author: Tessa H. Volle
Publisher:
ISBN:
Category : Concrete bridges
Languages : en
Pages : 74
Get Book Here
Book Description
