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The empirical design of reinforced concrete bridge deck slabs of girder bridges, referred to as only ‘deck slabs,’ is the most efficient design method because it recognizes the inherent arching action that exists in these slabs. Because of the arching action, the deck slabs fail in a punching shear mode under much higher wheel loads than the loads that would make them fail in bending; it is noted that failure in bending assumes the absence of the arching action. The Canadian Highway Bridge Design Code provides specifications for the empirical design of deck slabs. As the term ‘empirical design’ implies, this method is based on experimental evidence rather than analytical methods. A computer program, PUNCH, based on an analytical method, was developed to analyze the failure loads of externally restrained deck slabs, also referred to as ‘steel-free deck slabs,’ which do not contain embedded reinforcement for strength. In this program, it is assumed that the transverse confinement to deck slabs is provided by steel straps lying outside the deck slabs. Thus, this program only models the behavior of externally reinforced bridge deck slabs accurately. For internally reinforced bridge deck slabs, the stress-deformation behavior of steel in concrete is investigated in experimental evidence on concrete prisms, each with an embedded central steel bar, which has confirmed that when these prisms are subjected to tensile forces through the steel bars, the axial stiffness of the composite prisms is initially much larger than that of the bare steel bar, and decreases nonlinearly with the increase in the magnitude of tensile force. A reinforced concrete prism can thus be conceptually replaced by a hypothetical equivalent steel bar, the diameter of which is larger than that of the bare steel bar and decreases with the increase in the magnitude of the tensile force. This thesis attempts to modify the program PUNCH to analyze deck slabs with embedded steel bars by replacing t

This study introduces an innovative Bridge Weigh-in-Motion (BWIM) approach, utilizing a geophone, a novel sensor in the field of Structural Health Monitoring (SHM). Vehicle overloading poses a serious threat to bridge safety and service life. Loaded vehicles exert excessive stress on bridge decks, road pavements, and girders, leading to accelerated degradation of bridge structural components. Therefore, accurate information regarding real traffic loads, especially heavy vehicles, is critical for assessing bridge health. The proposed BWIM system combines geophones and strain sensors to accurately determine axle loads, axle spacing, and Gross Vehicle Weight (GVW) in regular traffic flow. The research methodology consists of bridge span instrumentation, data acquisition, processing, storage, and analysis, detailing the methods for extracting vehicle characteristics from measured bridge responses. Validation is done with field experiments on a real instrumented bridge in Winnipeg, Canada. This study focuses on loaded trucks. Velocity measurements exhibited an error range of -5% to 3.8%, with a confident 95% interval of -0.4% to 0.54% and an R2 value of 0.95, based on a sample of 64 vehicles. GVW calculations demonstrated an error range of -4.6% to +3.2%, and 95% confidence interval of -2.7% to 3.2%, derived from 6 runs of known GVWs. Axle detection accuracy was 95%, assessed across a sample of 41 trucks exceeding 150 kN in GVW. Axle spacings and loads were calculated in the error ranges of -10.52% to 7.8% and -4.97% to 10.48%, respectively. Confidence intervals for these metrics ranged from -2.4% to 3.2% and 1.05% to 8.6%, respectively. This study offers a contribution to the domain of SHM and Civionics, providing a reliable solution for axle detection of loaded trucks and assessing real traffic loads on instrumented bridges.

Bridges are vital component of a country’s transportation system and its economy. However, large number of ageing bridges are either structurally or geometrically deficient in some way. In recent years, the remaining life of ageing bridges, were calculated by detailed evaluation and damage assessment using structural health monitoring (SHM) techniques integrating bridge-weigh-in-motion (BWIM) systems. The field study of an existing BWIM system in Winnipeg, Manitoba was conducted on the Prototype Bridge. This work was extended to analysis and comparison of the algorithms adopted on the Prototype Bridge which provided deep insight in identifying the sources of error in BWIM systems. It was followed by a study on fatigue assessment of steel girder bridges. This research contributes by incorporating field measurements from BWIM system on the Prototype Bridge to estimate fatigue loading and damage assessment. In analytical phase, a simply supported beam subjected to moving and pulsating load was investigated for signal simulation and filtering in MATLAB. This was done as an initial exercise to understand dynamic effects of the load and its relevance to bridge natural frequency. This work was presented in a conference proceeding, attached in appendix. The experimental part of this work aims to identify sources of error in BWIM systems with the aid of the Model Bridge and verify area method, tested on the Prototype Bridge. The method was further investigated on the Model Bridge to obtain 95% confidence interval over real bridge BWIM testing. Model bridge structure was fabricated using polycarbonate. The model was designed to have natural frequencies like the Prototype Bridge. It was instrumented at two different locations with piezoelectric sensors for estimating velocity, transverse position, and class of model truck. It was instrumented with electrical strain gauges at three transverse locations for estimating Gross Vehicle Weight (GVW) of model truck. Video camera was u

This thesis focusses on the development of full-scale experimental program for testing rehabilitated metal culvert pipe assembled from corrugated steel plates and development of testing facility for testing rehabilitated structures until failure. The metal culvert pipe in arch geometry was rehabilitated using steel fiber reinforced shotcrete liner reinforced with pre-rolled reinforcement bars and studs. The condition of distressed field structures was simulated by inducing the crown defect along the longitudinal seams, where all the crown bolts were removed. The rehabilitated culvert pipe was buried in 0.6 m of shallow soil cover and was tested statically under simulated single wheel pair pad loading representing the geometry of CL-625 ONT dual tire truck footprint. The performance of the rehabilitated test culvert pipe was monitored during backfilling and during live load testing. Then, the rehabilitated test culvert pipe was loaded to its ultimate limit state until the failure of compacted granular fill surface at the top. Results showed that, the ultimate limit state was achieved at a load approximately eight times the service load. The conduit walls of shotcrete lined test culvert pipe exhibited relatively rigid behaviour with very low horizontal and vertical deflections at ultimate limit state. At the load equal to almost four times the service load, the rehabilitated culvert pipe showed tensile cracking at the crown location along the longitudinal seam where the crack propagated throughout the length of the pipe. No signs of circumferential cracking were observed in the test pipe at any load stage. Assessment of composite interaction behaviour of metal culvert pipe—rebar—shotcrete liner showed that no interaction was achieved at the crown location while full interaction was achieved at shoulder and spring lines. Rebar cage embedded in the shotcrete liner enhanced the flexural rigidity of the liner in addition to providing it with more ductility.