Influence of Precast Concrete Panel Surface Condition on Behavior of Composite Bridge Decks at Skewed Expansion Joints

Influence of Precast Concrete Panel Surface Condition on Behavior of Composite Bridge Decks at Skewed Expansion Joints
Author: Kristen Shawn Donnelly
Publisher:
Total Pages: 242
Release: 2009
Genre: Concrete bridges
ISBN:

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.

Experimental Evaluation of Full Depth Precast/prestressed Concrete Bridge Deck Panels

Experimental Evaluation of Full Depth Precast/prestressed Concrete Bridge Deck Panels
Author: Mohsen A. Issa
Publisher:
Total Pages: 278
Release: 2002
Genre: Concrete bridges
ISBN:

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.

Bridge Deck Joint Performance

Bridge Deck Joint Performance
Author: Ronald L. Purvis
Publisher: Transportation Research Board
Total Pages: 58
Release: 2003
Genre: Bridges
ISBN: 0309069572

TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 319: Bridge Deck Joint Performance presents the state of the practice on commonly used expansion joint systems in bridges by summarizing performance data for each system type and by providing examples of selection criteria and design guidelines.

Designing for Deck Stress Over Precast Panels in Negative Moment Regions

Designing for Deck Stress Over Precast Panels in Negative Moment Regions
Author: Keaton Munsterman
Publisher:
Total Pages: 210
Release: 2017
Genre:
ISBN:

One of the leading causes of structural deficiencies in the United States Bridge Inventory is related to deterioration and durability problems with concrete bridge decks (NCHRP 2004). The primary issue with bridge decks is related to cracking of the concrete that provides a direct conduit for moisture and other corrosion agents to permeate and attack the reinforcing steel. Adequate reinforcing steel is needed in the deck to minimize crack widths and therefore limit corrosion of reinforcing steel. A particular case of interest occurs when the bridge deck is constructed using partial-depth precast concrete deck panels (PCP) with cast-in-place (CIP) concrete topping. When this type of deck construction is used over the negative moment region of continuous steel or concrete girders, the amount of reinforcing steel that should be placed within the CIP concrete topping to provide adequate crack control is not currently well understood. This thesis is part of a larger study being conducted for the Texas Department of Transportation that is examining this issue. In the study reported in this thesis, two newly constructed bridges were instrumented to monitor the behavior of the bridge deck. These bridges did not use continuous girders, but rather had simply supported prestressed concrete girders, with a bridge deck constructed using a “poor-boy” construction joint detail over interior bents. Each bridge utilized three different reinforcement layouts centered over an interior bent within the poor-boy joint detail. Strain gages in each portion provided constant readings to display the distribution of strain across the bridge deck. Each bridge was monitored over a period from when the deck was cast until when the bridge was opened to traffic. Live load tests were also conducted to provide data on strains induced by heavy trucks. Based on the field data, no clear correlation was found between the amount of steel added and the strain measured. However, based on the measured data combined with field observations of cracking, the current standard reinforcement appears to be adequate in controlling the crack widths for the poor-boy deck detail. While the poor-boy deck joint detail is different from deck details used over negative moment regions of continuous girders, this data provides useful insights in to bridge deck behavior that will help guide future phases of the larger study.

Behavior of Precast Bridge Deck Joints with Small Bend Diameter U-Bars

Behavior of Precast Bridge Deck Joints with Small Bend Diameter U-Bars
Author: Cheryl Elizabeth Chapman
Publisher:
Total Pages: 86
Release: 2010
Genre:
ISBN:

The Interstate Highway System plays a vital role in our economic development by providing a continuous corridor for transporting goods and services. Currently, there is a need for repair and expansion of the existing highways, which include all bridges along its path. Because of the high demand for the highway system, repair and expansion must occur rapidly and efficiently. In recent years, precast bridge deck systems have become an efficient way to reduce construction time during repair. This thesis presents the experimental research of the behavior of the U-Bar joint detail used in precast bridge deck systems. This detail consists of staggered reinforcement extending beyond the precast deck portion into the joint. Six specimens utilizing the U-Bar detail were constructed and tested. Three specimens were tested in flexure to simulate the forces applied in a longitudinal deck joint, while three specimens were tested in pure tension to simulate the forces experienced in a transverse deck joint located over an interior pier. A tight 180° bend at 3d[subscript b] was desired in order to minimize the thickness of the deck. To achieve this tight bend, deformed wire reinforcement was chosen for the U-Bar detail due to the favorable material properties of deformed wire reinforcement. The purpose of the testing was to determine if the joint details could generate a precast deck system that could emulate the monolithic cast-in-place deck systems already in use. For monolithic behavior in a precast deck system, the joints must be able transfer shear, tension and moments. In this research, the joint overlap length was the most dominant variable, and should not be less than 152.4 mm (6"). The precast bridge deck joint should consist of high strength concrete with f'[subscript c] of at least 68.9 MPa (10 ksi). The longitudinal reinforcement spacing should be no greater than 152.4 mm (6").

Bridge Deck Analysis

Bridge Deck Analysis
Author: Damien L. Keogh
Publisher: CRC Press
Total Pages: 292
Release: 2005-08-09
Genre: Architecture
ISBN: 9780203984147

The definitive text in the field of Bridge Deck behaviour and analysis Bridge Deck Analysis is an essential reference for civil and structural engineers. It provides bridge designers with the knowledge to understand the behaviour of bridge decks, to be familiar with, and to understand the various numerical modelling techniques, to know which technique is most suited. The book covers the grillage analogy, dedicates a chapter to the modelling and analysis of integral bridge forms and also provides guidance of the application of the finite element method.