Showing papers on "Deck published in 2000"

Safety system for a closed compartment of a vehicle

Abstract: A release system adapted for use in opening a deck lid of a vehicle includes a gas operable assist device and at least one of a manual input device and an occupant detector. The release system is positionable within a compartment at least partially closed by the deck lid. The compartment has a release mechanism for opening the deck lid and the release system is adapted for operation from the interior of the compartment. The gas operable assist device is connectable to the release mechanism and is operable to actuate the release mechanism to open the deck lid in response to a user input to the manual input device or a detection of an occupant within the compartment by the occupant detector. The gas operable assist device includes at least one of a compressed gas container and a pyrotechnic element.

The structural behaviour of steel frames with composite floorslabs subject to fire: Part 1: Theory

Abstract: This paper presents the development of a new design method for calculating the performance of steel framed buildings, with composite flooring systems, subject to fire. This design method is based on the results from a series of full-scale fire tests on an eight-storey steel framed building, together with associated theoretical and further experimental investigations. The results from this work show that the performance for composite steel deck flooring systems in fire is under-utilised in current design procedures. This is owing mainly to the ability of lightly reinforced composite slabs to bridge over the supporting fire-damaged steel beams and transfer load, using membrane action, to the undamaged parts of the steel structure. From these observations a simple design method is developed that is based on a holistic, rather than an elemental, approach. This allows the various interactions between the components of a composite slab, supported by a grillage of steel beams, to be taken into account, producing cheaper and more innovative, site-specific, fire-engineering solutions. A companion paper shows how this design method can be applied to practical buildings.

Investigation of dynamic cable–deck interaction in a physical model of a cable‐stayed bridge. Part I: modal analysis

Abstract: A description of an experimental investigation involving the study of the dynamic interaction between the cables and the deck/towers system in cable-stayed bridges is presented. The work was carried out on a physical model of a cable-stayed bridge (the Jindo Bridge, in South Korea), whose characteristics of stiffness and mass have been conveniently scaled. Standard modal analysis tests were performed using both an electrodynamic shaker and a shaking table, leading to the creation of a high-quality database, characterizing the dynamic behaviour of the bridge. The study shows the existence of a clear dynamic interaction between the cables and the deck/towers system, associated with the appearance of several groups of mode shapes, at closely spaced frequencies, involving different cable movements, but similar configurations of the girder and towers.

A systematic analysis and design approach for single-span FRP deck/stringer bridges

Abstract: There is a concern with worldwide deterioration of highway bridges, particularly reinforced concrete. The advantages of fiber reinforced plastic (FRP) composites over conventional materials motivate their use in highway bridges for rehabilitation and replacement of structures. In this paper, a systematic approach for analysis and design of all FRP deck/stringer bridges is presented. The analyses of structural components cover: (1) constituent materials and ply properties, (2) laminated panel engineering properties, (3) stringer stiffness properties, and (4) apparent stiffnesses for composite cellular decks and their equivalent orthotropic material properties. To verify the accuracy of orthotropic material properties, an actual deck is experimentally tested and analyzed by a finite element model. For design analysis of FRP deck/stringer bridge systems, an approximate series solution for orthotropic plates, including first-order shear deformation, is applied to develop simplified design equations, which account for load distribution factors under various loading cases. An FRP deck fabricated by bonding side-by-side box beams is transversely attached to FRP wide-flange beams and tested as a deck/stringer bridge system. The bridge systems are tested under static loads for various load conditions, and the experimental results are correlated with those by an approximate series solution and a finite element model. The present simplified design analysis procedures can be used to develop new efficient FRP sections and to design FRP highway bridge decks and deck/stringer systems, as shown by an illustrative design example.

Structural characterization of fiber-reinforced composite short- and medium-span bridge systems

Abstract: The paper describes the development of a new structural system for short and medium span bridges wherein use is made of both advanced composites and conventional materials such as concrete. The concept uses prefabricated composite tubes as girders which are then filled with concrete, after which a conventional precast or cast-in-place, or advanced composite, deck system is integrated to form the bridge superstructure. The paper presents experimental results of large-scale tests aimed towards the structural characterization of the girders, anchorages, and girder-deck assemblies for both serviceability and ultimate limit states.

Performance of tube and plate fiberglass composite bridge deck

Abstract: A composite bridge deck system assembled from glass/polyester pultruded components has been developed. This system utilizes square tubes running transverse to the traffic direction, mechanically fastened and bonded together, and flat cover plates bonded to the tubes with an epoxy adhesive and through-anchored to the deck support structure using mechanical connectors. A 4.27 × 1.22 m section of the deck system integrally connected to the superstructure at a 1.2 m girder spacing was tested to failure under a single patch loading. The results indicate a factor of safety of 4 on strength and a deflection-to-span ratio of about L/300. Another section of the deck was fatigued to 3,000,000 cycles under service loading at a load ratio of \iR=0.1 and a nominal frequency of 3 Hz. Results from these tests indicate no loss in stiffness up to 3,000,000 cycles. Following the fatigue testing, this section was also tested to failure; no loss in strength was observed. In addition, a finite-element model of the laboratory tests was developed. The results from the model showed good correlation to deflections and longitudinal strains measured during the tests.

Rackable molded pallet

Abstract: A rackable pallet having improved structural integrity without adding material to increase the pallet weight. The pallet has a deck having a top and a bottom, a number of feet are formed extending downwardly from the deck, reinforcing members inserted in the deck top, and a lid having a top and bottom joined to the deck top and enclosing the reinforcing members. Ribs define an open grid pattern in the deck and lid, and hollow channels are formed in the deck and lid, which increases the strength of the pallet, without disproportionately increasing the volume or weight of material used. The hollow channels are formed at strategic locations in the lid top and the deck bottom. Foot straps mounted to the deck feet further improve the pallet structural integrity. Each foot strap is mounted to the feet with releasable shearable fasteners to simplify foot strap replacement and minimize foot strap damage.

Investigation of dynamic cable-deck interaction in a physical model of a cable-stayed bridge. Part II : seismic response

Abstract: The present paper describes an investigation of the effect of dynamic cable interaction with the deck and towers in the seismic response of a cable-stayed bridge. This study involved shaking table tests performed on a physical model of Jindo bridge, in order to validate two alternative numerical models, which differ in terms of consideration of coupled cable/deck and towers modes. The response to artificial accelerograms was calculated and correlated with measured data. Additional numerical simulations are presented in order to clarify the role that cables play in the attenuation or amplification of the structural response. It was found that the cable interference with global oscillations may cause a decrease of the bridge response. However, this ‘system damping’ may not develop in the case where a narrow-band excitation is applied, causing large amplitude of vibrations of some cables, with significant non-linearity, and inducing higher-order modes. Copyright © 2000 John Wiley & Sons, Ltd.

Ground-Penetrating Radar for Network-Level Concrete Deck Repair Management

Abstract: The lack of an effective bridge deck condition assessment tool prompted a collaborative research program between Dalhousie University DalTech (Halifax, Nova Scotia, Canada) and the Nova Scotia Department of Transportation and Public Works to assess the accuracy and variability of ground-penetrating radar (GPR) for asphalt-covered, reinforced-concrete bridge deck deterioration estimates. The quantity and location of GPR-predicted deterioration on nine bridge decks was compared to actual deterioration detected using the half-cell potential and chain drag survey methods. Good spatial correlation and excellent quantitative correlation were observed between the GPR predictions and the actual deterioration found on the nine decks. The findings have demonstrated that GPR can provide management with a valuable tool for estimating deck repair quantities and prioritization of potential repair candidates on a network level.

Subsea well intervention vessel

Abstract: A subsea well intervention vessel comprising a dynamically positionable tanker and direct well intervention equipment mounted on a deck of the tanker. The direct well intervention equipment may be mounted on a superstructure above the main deck of the tanker and includes equipment for underbalanced non-rotating drilling and hydrocarbon liquid separation. The liquid separation equipment is coupled to storage tanks of the tanker so as to receive separated hydrocarbon liquids for storage purposes.

Laboratory and field testing of composite bridge superstructure

Abstract: Bridge rehabilitation utilizing a hybrid fiber-reinforced polymeric composite has recently been completed in Blacksburg, Va. This project involved replacing the superstructure in the Tom's Creek Bridge, a rural short-span traffic bridge with a timber deck and corroded steel girders, with a glue-laminated timber deck on composite girders. To verify the bridge design and to address construction issues prior to the rehabilitation, a full-scale mock-up of the bridge was built and tested in the laboratory. This setup utilized the actual composite beams, glue-laminated timber deck panels, and the skewed geometry implemented in the rehabilitation. Following rehabilitation, the bridge was field tested under controlled conditions (vehicle load and position). Both tests examined service load deflections, girder strains, load distribution, degree of composite action, interpanel deck deflections, and impact factor. The field test results indicate a service load deflection of L/400 under moving loads and a high factor...

Easy connect and disconnect faucet spout assembly

Abstract: A faucet spout assembly 20 is mountable on a deck 80 from above the deck 80. The assembly 20 is connected to a water supply line that extends through an opening 82 in the deck 80 . The assembly 20 includes a spout 22 removably connected to a mounting plate 44 . A first and a second member 26 and 50 , respectively, connect to non-rotatable nut member 64 carrying a retainer member 72 whereby, on shifting the nut member 64 toward the underside of the deck 80 , the retainer member 72 will clamp the assembly 20 to the deck 80.

Deck plank cover

Abstract: A deck plank cover made from a plastic material, such as a wood composite, wherein the deck plank cover is designed to be affixed to the top surface of a preexisting deck plank The deck plank cover is useful for repairing or protecting mildly deteriorated or deteriorating wooden deck planks of typical wooden decks The deck plank cover may be affixed directly to the top surface of the existing wooden deck planks, and serves to substantially protect the wooden deck planks from further exposure to the elements The deck plank cover of the present invention may also be applied to non-deteriorated wooden deck planks to prevent the onset of deterioration and to alleviate the need for treatment of the subjacent wooden deck planks with chemical preservatives The deck plank cover preferably simulates the look of real wood, and may be produced in various cross-sectional shapes and sizes and from a variety of plastic materials

Canadian Bridge Design Code Provisions for Fiber-Reinforced Structures

Abstract: This paper presents a synthesis of the design provisions of the Canadian Highway Bridge Design Code for fiber-reinforced structures. These include structures reinforced with fiber-reinforced polymer and fiber-reinforced concrete (FRC). The provisions apply to fully, or partially, prestressed concrete beams and slabs, non-prestressed concrete beams, slabs, and deck slabs, FRC deck slabs of slab-on-girder bridges, stressed wood decks, and barrier walls. Test methods to confirm the tensile strength of fiber-reinforced polymer and the postcracking strength of FRC are given.

Elevatingly folding unit of electric exercise treadmill

Abstract: The present invention relates to an elevatingly folding unit of an electric exercise treadmill having a main frame, a deck frame, a belt-driving assembly and an elevatingly folding unit. The deck frame is interposed between two foot seats, including a deck and a continuous belt. And the belt-driving assembly is disposed at one end of the deck frame to drive the continuous belt for a cyclical rotation. In addition, the elevatingly folding unit is used for the deck frame to perform an elevating or a folding action. This folding unit makes use of a servomotor to drive the transmission spindle through a gearbox such that a slide shaft is movable forward and backward. The slide shaft is pivoted with two elevating rods while the other end thereof is pivotally mounted on a fixing shaft of the deck frame. When the slide shaft moves forward and backward, a relatively elevating action will be created at one end of the deck frame. Moreover, when the slide shaft moves, the folding support pivoted at one end of the foot seat and a movable support are pivotally joined with the deck frame such that a relatively folding action of the deck frame is created.

Experimental behavior of full-depth precast concrete panels for bridge rehabilitation

Abstract: An effective and economic design concept can be implemented for the rehabilitation of existing highway bridges and new bridge construction involving the application of full-depth precast or precast prestressed concrete panels that can be installed on concrete or steel beams To verify the effectiveness of these structural systems, an experimental study was conducted on the proposed system to investigate the joints between adjacent precast panels, shear pocket connection between the precast panels and its supporting system to achieve full composite action, and the amount of concentric prestressing force that is needed in the deck system in the longitudinal direction to provide continuity and to secure the tightness of the transverse joints The experimental objectives of the study included modeling a continuous prototype bridge with full-depth precast panels on steel stringers These models were subjected to static and fatigue simulated American Association of State Highway and Transportation Officials truck loading For the purpose of studying the effect of posttensioning, the bridge deck system for the first bridge model was not posttensioned longitudinally, while the decks for the second and third bridge models were posttensioned with a prestress level of 143 MPa (208 psi) and 262 MPa (380 psi), respectively The effect of posttensioning was clearly evident in that first cracking initiated in the transverse joints near the central support (maximum negative moment region) for the nonposttensioned bridge model, while first cracking initiated in the central panel (over the central support) for the last two bridges The applied load that caused the nonposttensioned bridge deck to crack was approximately one-third that of the posttensioned bridge deck models

Threaded anchor for poured concrete metal deck floors and wood frame floors

Abstract: An internally threaded insert anchor (41) for use in poured concrete floors having metal decking or wood form is described which provides setal deck or wood form, prior to the concrete being poured. Once locked into the concrete floor (61), the threaded insert anchor (41) provides easy attachment for the support rods that carry the racks of utility, piping and ceiling grid systems for the building. Each threaded insert anchor (41) is capable of accepting two different size rods or bolts with different thread cuts. The internal threaded apertures (63, 65) are protected from concrete intrusion during the pour by the plastic or metal sleeve (53). Moreover, the anchors are designed so that subsequent spraying of the ceiling with fire retardant or insulation foam will not penetrate into the threaded apertures, so as to prevent subsequent entry of the support rods.

Quick-install assembly for a single control faucet

Abstract: A quick-install assembly for a single control faucet connected to water supply lines that extend through an opening in a deck to which the faucet is mounted, which assembly has a collar of larger diameter than the diameter of the opening of the deck and positioned from above the deck to be disposed at the opening of the deck The collar has a pair of ears formed thereon that extend over the opening in the deck A pair of fasteners are operatively engaged from above the deck to be threadedly connected to the ears to be disposed from above through the opening of the deck A retainer is threadedly connected to the fasteners and includes a pair of swing flaps thereon adapted to be axially shifted toward and away from the collar responsive to the direction of rotation of the fasteners The pair of swing flaps rotate on the fasteners between a closed position that provides a small dimension that passes through the opening of the deck and an open position that provides a long dimension with each swing flap pivoted outwardly so that when the retainer is disposed below the deck and the retainer is shifted upwardly each of the swing flaps will clamp against the underside of the deck to clamp the quick-install assembly thereto Lastly, connecting device are operable from above the deck to connect the faucet to the collar whereby the faucet will be mounted upon the deck

Field Performance of Epoxy-Coated Reinforcing Steel in Virginia Bridge Decks

Abstract: In this study, the corrosion protection performance of epoxy-coated reinforcing steel (ECR) was evaluated using approximately 250 concrete cores from 18 bridge decks in Virginia. The decks were 2 to 20 years old at the time of the investigation. The deck field inspections included a crack survey and cover depth determination in the right traffic lane. A maximum of 12 cores with the top reinforcement randomly located in the lowest 12th percentile cover depth were taken from each bridge deck. Because of the safety concerns associated with taking cores from the lower steel mat, and to minimize damage to the bridge, a maximum of only 3 cores were taken through the truss bars. The laboratory evaluation of the concrete cores included a visual examination and a determination of the carbonation depth, moisture content, absorption, percent saturation, and chloride content at a 13-mm depth. The rapid chloride permeability test was also performed for the surface and base concrete on samples obtained from the cores taken through the truss bars to determine chloride permeability. The ECR inspection consisted of a visual examination, a damage evaluation, and a determination of coating thickness and adhesion. The condition of the steel underneath the epoxy coating was also evaluated. Adhesion loss of the epoxy coating to the steel surface was detected in all but one deck that was 4 years old and older. The epoxy coatings were debonding from the reinforcing bars. Whereas a bonded coating can be expected to protect the steel, a debonded coating allows chlorides, moisture, and oxygen to reach the steel and initiate a rapid corrosion mechanism. Reinforcing bars in various stages of adhesion loss showed visible signs of a corrosion process underneath the coating, suggesting the ECR will provide little or no additional service life for concrete bridge decks in comparison to bare steel. Other systems that will provide longer protection against chloride-induced corrosion of the reinforcing steel with a higher degree of reliability should be considered.

Experimental investigation of the role of reinforcement in the strength of concrete deck slabs

Abstract: To study systematically the role of each layer of steel reinforcement in conventionally reinforced deck slabs of girder bridges, a full-scale model was built of a 175 mm thick concrete deck slab on

Aerodynamic Stability of Long-Span Suspension Bridges under Erection

Abstract: The aerodynamic instability of a long-span suspension bridge with a shallow streamlined box girder is a serious engineering concern, particularly during the early deck erection stage. Its characteristics are significantly influenced by the sequence of deck erection. Using the Hoga Kusten Bridge in Sweden as an example, this paper presents an analytical and experimental discussion regarding the evolution of flutter characteristics for a long-span suspension bridge, and a comparison of different erection sequences and analytical prediction of more stable configurations. The general feature of the flutter limit evolution with the erection program of midspan to pylons, which was previously evidenced by wind tunnel tests, has been successfully reproduced analytically, and the advantages of keeping nonsymmetric deck configurations were confirmed. The pylon to midspan program has never been employed for long-span girder bridges, but it was found to be, at least, aerodynamically favorable.

Dual deck dewatering screen

Abstract: A vibrating dual deck dewatering unit which includes a lower screen deck and an upper screen deck. Material being processed by the unit is discharged from the upper screen deck onto the lower screen deck in such a manner that excess water is allowed to backflow beneath the upper screen deck, while solids are directed in an opposite direction. The upper screen deck is provided with a jagged discharge lip which creates interruptions or gaps in the flow of discharged solids. The excess water which is discharged from the upper screen deck is allowed to backflow through the interruptions or gaps in the discharged solids that are created by the jagged discharge lip of the upper screen deck.

Method for constructing an offshore platform

Abstract: This invention provides a method for constructing an offshore platform by mating a self-floating deck (50) structure with a self-floating substructure. The self-floating deck structure may be a floating pier or barge (40), on which the desired equipment has been mounted. Mating is achieved by at least partially submerging the substructure, positioning the pier or barge (40) above it, and deballasting the substructure to create a vertical bearing force between the substructure and the pier or barge (40). Horizontal force may be transmitted between the deck (50) and substructure by a variety of mechanical, structural, and magnetic means.

Seismic methods in post construction condition monitoring of bridge decks

Abstract: Ultrasonic methods implemented in various types of integrated seismic devices can be successfully used in quality control and condition assessment of bridge decks. Of special interest are three ultrasonic techniques: ultrasonic body-wave (UBW), ultrasonic surface-wave (USW), and impact echo (IE). While the first two are used in a deck material characterization, the IE method is primarily used in evaluation of a corrosion induced delamination. The biggest advantages of the IE method over a current practice of chain dragging is that it allows detection of zones of delamination at various stages: from initial to progressed and developed, thus enabling better prediction of deterioration processes in the deck. To improve automation, accuracy and interpretation of results of the IE technique, the testing is simulated by the finite element method. Numerous finite element results confirm the ability of the IE method to accurately measure the position, extent and the stage of delamination. The finite element method was successfully used in simulation of two probable scenarios of delamination progression: expansion/growth of a single small delamination, and progressive linking of several smaller delaminations. Elements that can be used in recognition of the two processes are described and can be used in long term monitoring and prediction of deterioration processes. Issues related to finite element modeling of wave propagation in bridge decks and finite element analysis results interpretation are discussed too.