Comparison with the Response of a Flexible Bridge

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DEMAND RESPONSE PILOT COMPARISON

DEMAND RESPONSE PILOT COMPARISON

Direct feedback includes communication techniques, which are immediate and directly available to the consumer. This includes in house displays, websites, or ambient displays. Consumers have continuous direct access to these sources. They provide such information as: how much energy is consumed at any given time, and the current cost or savings made. It will sometimes also allow consumers to set personal consumption goals and warn them if they are exceeded. Some feedback displays systems will provide information to the consumer about how much each of their various appliances are consuming individually. This brings the added benefit of security and ease. For example there are systems now through which a consumer can see if they have left their iron plugged in or their stove on, through their mobile phone. If the program includes automation – they will be able to turn these devices on/off or down remotely. Direct feedback can be provided in many formats, through a wide range of technology and as a re-enforcement tool within demand response pricing and automation programs.
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Electromyographic and kinetic comparison of a flexible and steel barbell

Electromyographic and kinetic comparison of a flexible and steel barbell

MATERIALS AND METHODS Experimental Approach to the Problem This randomized control research design reports data from a combination of a machine-driven experiment and a human subject experiment conducted within the same year in which a FB is compared to a SB, which is considered the control for both experiments. The first experiment incorporated a lifting machine set atop a force plate to measure ground reaction forces (GRFs) in response to lifting both a SB or FB (Tsunami Bar ® , West Columbia, SC), both loaded with plates for a total weight of 47.6 kg. Each bar was lifted at a frequency of 52 repetitions per minute and a linear travel distance from the bottom to top position of 30.5 cm. The human subject experiment was also designed to compare the SB and FB for the SQ exercise by measuring muscle activity with EMG and GRFs. The total weight of the loaded bar for the human subjects was set to 30% of their one repetition maximum (1RM) (Kraemer & Ratamess, 2004) for each respective lift and was also lifted at a rate of 52 repetitions per minute. Procedures are described in detail below for both the machine and human subject protocols.
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A Flexible Comparison Process as a Critical Mechanism for Context Effects

A Flexible Comparison Process as a Critical Mechanism for Context Effects

70 interesting account of the present data, particularly as it varies across presentation format. Further development of these models is needed to test them in the present framework. Regardless, none of the tested models in their present forms appear to provide a full account of the relationship between choice and response time. This calls into serious question whether the sequential sampling framework provides enough psychological insight to outweigh its high computational cost. Rather, it is possible that preferential choice represents a decision process that is too qualitatively distinct from the perceptual scenarios in which such models have traditionally found success. Indeed, the present data raise the possibility that a mixture of heuristic and deliberative processes are involved, in which case trying to fit the entire set of response time data with a single parsimonious process may not be useful. Future work in model development might therefore seriously consider taking a step back to determine how best to build a tractable model that still captures the critical relationship between choice and response time.
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Wind-induced response of bridge stay cables in unsteady wind

Wind-induced response of bridge stay cables in unsteady wind

reaches the critical value, large amplitude cable response would be triggered and cannot be suppressed unless the structural damping of the cable is increased to a certain level. In the current case as shown in Figure 4-7, the maximum cable damping ratio needs to be increased to at least 1.5% to avoid the occurrence of any unstable motion. In practice, this can be achieved by attaching external dampers to the cable. Further, it can be seen from Figure 4-7 that an increase of the cable-wind relative angle φ seems would “push” the instability range to higher Reynolds number. This is reasonable since the cable orientation against the wind would affect the critical Reynolds number range. The smaller this relative angle φ is, the earlier it would reach the critical Reynolds number range. In Figure 4-7, the instability range associated with the five studied relative orientation angles φ corresponds to a Reynolds number range of 2-510 5 . It is interesting to note that the instability region associated with the cross-flow case has a comparable size with that of the most critical inclined case of φ=60. A stability boundary is developed by connecting the outmost point of the unstable regions for every angle φ which is shown by a solid thick line in Figure 4- 7. The obtained stability boundary line leads to a closed instability region, which is a clear indication that once the critical Reynolds number regime is passed, the unstable cable response can be suppressed. This confirms the earlier proposed excitation mechanisms of dry inclined cable galloping that the emergence of critical Reynolds number regime is indeed an important contributing factor. As a comparison, the U r ‒ S c relations proposed by Saito et al. (1994) and derived based on the wind tunnel testing results by Cheng et al.
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Comparison Between Staad and Etabs on Skew Bridge with Different Span

Comparison Between Staad and Etabs on Skew Bridge with Different Span

© 2017, IRJET | Impact Factor value: 6.171 | ISO 9001:2008 Certified Journal | Page 1665 3. LOAD ON BRIDGE DECK MODELS The vehicular live load consist of a set wheel loads and are treated as uniformly distributed loads acting at contact areas, one classes of load i.e. IRC 70R are considered for analysis. The peak values of critical structural response parameter such as longitudinal sagging bending moment and t o r s i o n a l moment are analyzed. Different positions of each type of loading systems are considered of IRC 6:2014
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A Comparison of Nondestructive Testing Backcalculation Techniques for Rigid and Flexible Pavements

A Comparison of Nondestructive Testing Backcalculation Techniques for Rigid and Flexible Pavements

has noted that ELMOD is well suited for processing large batches of FWD readings without constant attention from the user (14). ELMOD uses an iteratation-based backcalculation procedure that can forward model the pavement response using a variety of techniques. ELMOD is also known for its ability to model the temperature-dependent behavior of HMA and the nonlinear response of subgrade and aggregate materials (29). Older versions of the software were limited to two different types of forward calculation. The first option was a common deflection basin matching routine. The other option was based on matching the radius of curvature of the deflection basin instead of trying to match the basin as a whole. The literature suggests that the radius of curvature option is more accurate, but still
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A Study on Dynamic Response of Bridge Deck Slab under Moving Loads

A Study on Dynamic Response of Bridge Deck Slab under Moving Loads

[1] Humar Jagmohan L. and. Kashif Ahmed H “dynamic response analysis of slab-type bridges”, Journal of structural engineering, 1995.121:48 [2] Broquet Claude, Bailey Simon F., Mario Fafard, and Bru Eugen “Dynamic Behavior of Deck Slabs of Concrete Road Bridges”, journal of bridge engineering, 2004-9 [3] Ayad Thabit Saeed Al-Ghabsha, Dr. Mohamad Najim “dynamic analysis of bridges subjected to moving vehicles”, Al-Rafidain Engineering Vol.14 No.4 2006 [4] Ji Jing , Zhang Wenfu , Zhao Wenyan, Yuan , Chaoqing Yang, “Analysis and Comparison on Dynamic Characteristics of the Bridge Subjected to Moving
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An Efficient Vertical Seismic Response of a Precast Segmental Bridge Superstructure: A Study

An Efficient Vertical Seismic Response of a Precast Segmental Bridge Superstructure: A Study

Steel bridges are commonly considered to perform nicely in earthquakes, and the implication is regularly made that they have to beused extra regularly in seismically active areas. It seems thatthis argument is based totally on the truth that few if any, steel bridgeshave collapsed in North American earthquakes, in comparison to theoverall performance of structural concrete bridges.If a metal bridge is described as one with a metal superstructureand a metal substructure, there are only a few of these in westernNorth America, or even fewer had been subjected to strongfloor motions within the remaining decade or so. However, if a steel bridgeincludes those with concrete substructures ~piers, and columns!The populace will increase significantly, but continues to be a long way less than thatof structural concrete bridges ~in western North America!. Evenso, overall performance facts for those bridges are tough to locate, and especially for bridges subjected to sturdy shaking.
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Comparison of Bridge Rehabilitation versus Bridge Replacement Concepts

Comparison of Bridge Rehabilitation versus Bridge Replacement Concepts

not abundant; this drives the cost up. Lightweight aggregate is softer than conventional aggregate, and this leads to a less durable deck. For these reasons, the Bridge Working Group eliminated lightweight concrete for consideration. FRP decks are still a relatively new technology. Because there is limited historical information on FRP, there are concerns that it is not sufficiently durable. The movable span of the Broadway Bridge has recently been retrofitted with an FRP deck rather than the open grid deck that is typically used to reduce weight on movable bridges. The Bridge Working Group decided that FRP would not be considered for the vehicular roadway, but would be used for sidewalks and bike paths. This decision was based primarily on the limited amount of historical data available regarding FRP long term performance.
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A Comparison of Flexible Schemas for Software as a Service

A Comparison of Flexible Schemas for Software as a Service

In comparison to the Sparse Columns mapping in SQL Server, HBase exhibits a decrease in performance that ranges from one to two orders of magnitude depending on the op- eration. One reason for this decrease is the reduced expres- sive power of the HBase APIs, which results in the need for the adaptation layer. This effect is particularly severe for reports and updates, where SQL Server with adaptation also shows a significant decrease in performance. These re- sults are consistent with [9], which shows that high-volume data-processing tasks such as reporting are more efficiently processed by shipping queries to the server rather than by shipping data to the client. The performance decrease for updates is primarily due to the fact that the adaptation layer submits changes one at a time rather than in bulk. HBase has a bulk update operation, however it appears that, in the version we used, changes are not actually submitted in bulk unless automatic flushing to disk is turned off. In any case, this problem with bulk updates should be easy to fix.
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Experimental Investigation of the Seismic Response of Bridge Bearings

Experimental Investigation of the Seismic Response of Bridge Bearings

16. Abstract The Illinois Department of Transportation (IDOT) commonly uses elastomeric bearings to accommodate thermal deformations in bridges. These bearings also present an opportunity to achieve a structural response similar to isolation during seismic events. IDOT has been developing an earthquake resisting system (ERS) to leverage the displacement capacity available at typical bearings in order to provide seismic protection to substructures of typical bridges. The research program described in this report was conducted to validate and calibrate IDOT’s current implementation of design practice for the ERS, based on experiments conducted on typical full-size bearing specimens, as well as computational models capturing full bridge response. The overall final report is divided into two volumes. This first volume describes the experimental program and presents results and conclusions obtained from the bearing and retainer tests. The experiments described in this volume provide data to characterize force-displacement relationships for common bearing types used in Illinois. The testing program comprised approximately 60 individual tests on some 26 bearing assemblies and components (i.e., retainers). The testing program included (1) Type I elastomeric bearings, consisting of a steel-reinforced elastomeric block vulcanized to a thick top plate; (2) Type II elastomeric bearings, distinct from Type I bearings with a steel bottom plate vulcanized to the bottom of the elastomeric block, and a flat sliding layer with polytetrafluoroethylene (PTFE) and stainless steel mating surfaces between the elastomer and the superstructure; and (3) low-profile fixed bearings. Tests conducted to simulate transverse bridge motion also included stiffened L-shaped retainers, consistent with standard IDOT practice. Tests were conducted using monotonic and cyclic displacement protocols, at compression loads corresponding to a range of elastomer compression stresses from 200 to 800 psi. Peak displacements from initial position ranged from 7-1/2 in. to 12-1/2 in., depending on bearing size. Test rates were generally quasi-static, but increased velocities up to 4 in./sec were used for bearings with PTFE and for a subset of other elastomeric bearings. On the basis of all of the experimental findings, bearing fuse force capacities have been determined, and appropriate shear stiffness and friction coefficient values for seismic response have been characterized and bracketed.
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Local buckling response of subsea flexible pipe

Local buckling response of subsea flexible pipe

68 problem can be solved with a few large increments. Besides faster convergence, the implicit methods employ equilibrium check after each increment to calculate the residual forces. This is a crucial check for finding snap-through points in the response of the structure. Also, equilibrium check improves contact interaction modeling in cases of using the penalty method. Penalty methods are generally framed in terms of the displacement variable with the contact stiffness defined as several orders of magnitude higher than surrounding elements. This may lead to an ill- conditioned system of equations and issues that may result in difficulties with solution performance. Furthermore, if the interface stiffness is under-constrained (i.e., low stiffness) then excessive penetration during contact is allowed that may lead to errors in the predicted interaction response with respect to local relative stiffness, and predictions of local displacement, velocity and acceleration [9-11]. This issue is further complicated through the interdependence on mesh density and stick-slip mechanisms [12]. These factors ultimately affect solution performance and, potentially, accuracy. Once implicit solver is used with Penalty method, the contact penetrations and forces must be within the defined contact penetration and force tolerances as well as the resultant forces caused by contact interaction are taken into account and checked by equilibrium criterion.
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MUSCLE RESPONSE WITH FLEXIBLE FIXED FUNCTIONAL APPLIANCE

MUSCLE RESPONSE WITH FLEXIBLE FIXED FUNCTIONAL APPLIANCE

From the significant decrease in EMG activity of masseter and anterior temporal muscles seen in our study, we support the view that passive ten- sion associated with viscoelastic properties of soft tissues rather than active contraction of the jaw closing muscles play an important role in mecha- nism of neuromuscular adaptation with flexible fixed functional appliance, because of a much longer duration of forces from passive tension18, 20. It is proposed that the insertion of Forsus in- duces motor reprogramming and result in postural adoption which in turn leads to a growth response. The muscle activity, in this study was examined over a period of six months of the treatment with a flexible fixed functional appliance and compared with untreated Class II div 1 malocclusion sub- jects who served as control group. All subjects in Group 2 were in the active phase of sagittal cor- rection by the end of 6 months wherein there was unbalanced and reduced number of occlusal con- tacts in the posterior dental arch segments. After six months the appliances were removed and ort- hodontic treatment was continued. Even though the flexible fixed functional appliance used in our study had presumably imposed alterations in the neuromuscular response in the treated subjects, and a complete neuromuscular adaptation had oc- curred as seen by the lack of statistically signifi- cant differences in EMG values at the start of the treatment and at the end of six months (1 vs. 5), a six month observation period may not be lengthy enough to draw definite conclusions. The possibi- lity of adaptation effects later with treatment is an important factor for which a long term investiga- tion needs to be undertaken.
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COMPARISON OF FRACTURE RESISTANCE OF CAD/CAM INTERIM BRIDGE AND CONVENTIONAL INTERIM RESIN BRIDGE

COMPARISON OF FRACTURE RESISTANCE OF CAD/CAM INTERIM BRIDGE AND CONVENTIONAL INTERIM RESIN BRIDGE

Interim bridges fabrication by conventional technique Group 2 and group 4 samples were fabricated by this technique using Telio lab PMMA and Vita VM CC materials. First waxing up for full anatomy dental interim bridge was done on every model, and then silicone key formed on it that registered the fine details of the waxing up. After set, silicone key removed and remaining wax cleaned off and block out for any undercuts was done, then separating fluid was applied using fine brush. Mixing powder and liquid in silicone bowel as manufacturer’s instruction was utilized with standard ratio and after reaching dough stage, the silicone key filled with material and seated back on model and placed in polymerizer for about 15 minutes with a pressure of 2 bar and temperature of 40- 50c. After polymerization, finishing and polishing for every interim bridge was made.
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A numerical investigation on the fire response of a steel girder bridge

A numerical investigation on the fire response of a steel girder bridge

The response of bridges subject to fire is an under researched topic despite the number of bridge failures caused by fire. Since available data shows that steel girder bridges are especially vulnerable to fire, this papers delves into their fire response by analyzing with a 3D numerical model the response of a typical bridge of 12.20 m. span length. A parametric study is performed considering: (1) two possibilities for the axial restraint of the bridge deck, (2) four types of structural steel for the girders (carbon steel and stainless steel grades 1.4301, 1.4401, and 1.4462), (3) three different constitutive models for carbon steel, (4) four live loads, and (5) two alternative fire loads (the hydrocarbon fire defined by Eurocode 1 and a fire corresponding to a real fire event). Results show that restraint to deck expansion coming from an adjacent span or abutment should be considered in the numerical model. In addition, times to collapse are very small when the bridge girders are built with carbon steel (between 8.5 and 18 minutes) but they can almost double if stainless steel is used for the girders. Therefore, stainless steel is a material to consider for steel girder bridges in a high fire risk situation, especially if the bridge is located in a corrosive environment and its aesthetics deserves special attention. The methodology developed in this paper and the results obtained are useful for researchers and practitioners interested in developing and applying a performance-based approach for the design of bridges against fire.
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Latent class recapture models with flexible behavioural response

Latent class recapture models with flexible behavioural response

features (like weather conditions), making capture more likely or more unlikely uniformly for all subjects at each occasion. These are called M t models, where occasion-specific capture probabilities are used. Finally, the probability of capture may depend on what happened during the previous capture occasions. Subjects may be more likely or less likely to be captured again after a capture, or a pattern of captures, depending on the experience. For instance, animals being fed during capture may become trap-happy, and looking forward to be captured and fed again. Models taking into account possible behavioural response to capture are tagged M b .
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Optimal Demand Response Program for Flexible Ramps Markets

Optimal Demand Response Program for Flexible Ramps Markets

From this perspective, international experiences and results about the application of DR where analyzed and it was observed that DRPs can be effectively recognized as possible solutions in the direction of a more flexible electrical network [ 13 ]. As mentioned before, the uncertainty of these resources has been already well discussed how- ever, Variability, is currently under investigation due to the increasing flexibility challenges caused by ascending penetration rate of nondispatchable RES in future power systems. Flexibility is de- fined as the ability of a system to deploy its resources and to respond to changes in the net load. With this in mind some wholesale markets have commenced new activities to meet their required flexibility such as increasing reserve capacity margins, starting fast response units, and withhold- ing some generation capacity. In this regard, one of the promising market renovations has been realized by defining new energy and reserve market mechanisms presented as "flexiramp" in Cal- ifornia ISO [ 14 ].
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Using Diffusion Distances for Flexible Molecular Shape Comparison

Using Diffusion Distances for Flexible Molecular Shape Comparison

A challenging aspect of measuring the similarity between two 3D shapes is to find a suitable shape descriptor that can be constructed and compared quickly, while still discriminating between similar and dissimilar shapes. Shape distribution [20] is the simplest and most widely used shape descriptor, which represents the shape descriptor of a 3D model as a probability dis- tribution sampled from a shape function measuring geo- metric properties of the 3D model. In particular, the distance histogram, also called D2, is one example shape distribution, which represents the distribution of Eucli- dean distances between pairs of randomly selected points on the surface of a 3D model. The key idea of shape distribution is to transform an arbitrary 3D model into a parameterized function that can easily be com- pared with others. In our case, the domain of the shape function provides the parameterization (e.g., the D2 shape distribution is a function parameterized by dis- tance), and random sampling provides the transforma- tion. The primary advantage of shape distribution is its simplicity, where the shape matching problem is reduced to sampling, normalization, and comparison of probability distributions. In spite of its simplicity, the shape distribution is expected to be useful for discrimi- nating the whole objects with different gross shapes, including invariance, robustness, efficiency, and general- ity. In general, the D2 histogram is computed by employing stochastic methods and it is formed by three steps: (1) first sampling uniformly random points from the shape surface, then (2) computing the Euclidean dis- tance between the sampled point pairs, and finally (3) constructing a distance histogram by counting how many samples fall into each of fixed sized bins. From the histogram, we reconstruct a piecewise linear func- tion which forms our representation for the shape distri- bution. In this paper, the main difference between our method and the original D2 is that we use diffusion dis- tance in a sense of diffusion distance instead of Eucli- dean distance in [20].
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Riparian and Riverine Wildlife Response to a Newly Created Bridge Crossing

Riparian and Riverine Wildlife Response to a Newly Created Bridge Crossing

Email: * jim.anderson@mail.wvu.edu Received September 11 th , 2012; revised October 23 rd , 2012; accepted November 4 th , 2012 ABSTRACT Construction of man-made objects such as roads and bridges can influence wildlife presence and abundance. We invest- tigated waterbirds, songbirds, anurans, turtles, small mammals, and furbearers along the Ohio River, WV, at a new bridge crossing, a 45-year-old bridge, and 1 or 2 islands with no bridge and at 3 distances from the bridge or center point at each site (0 m, 100 m, and 300 m). We sampled 19 waterbird, 60 songbird, 7 anuran, 5 turtle, 9 small mammal, and 4 furbearer species. Great blue heron (Ardea herodias) abundances were greater at the site with no bridge. Songbird composition differed among sites and between transects under and away from the bridge with higher abundances or association of rock pigeon (Columba livia) and cliff swallow (Petrochelidon pyrrhonota) under the bridges and lower abundances of Carolina wren (Thryothorus ludovicianus) and common yellowthroat (Geothlypis trichas) under the bridges. Total small mammal abundance, diversity, and richness were lower under the new bridge compared to other sites and distances. We conclude that overall the new bridge is causing minimal relative abundance impacts to wildlife.
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Damage Detection of a Continuous Bridge from Response of a Moving Vehicle

Damage Detection of a Continuous Bridge from Response of a Moving Vehicle

Copyright © 2014 Z. H. Li and F. T. K. Au. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper presents a multistage multipass method to identify the damage location of a continuous bridge from the response of a vehicle moving on the rough road surface of the bridge. The vehicle runs over the bridge several times at different velocities and the corresponding responses of the vehicle can be obtained. The vertical accelerations of the vehicle running on the intact and damaged bridges are used for identification. The multistage damage detection method is implemented by the modal strain energy based method and genetic algorithm. The modal strain energy based method estimates the damage location by calculating a damage indicator from the frequencies extracted from the vehicle responses of both the intact and damaged states of the bridge. At the second stage, the identification problem is transformed into a global optimization problem and is solved by genetic algorithm techniques. For each pass of the vehicle, the method can identify the location of the damage until it is determined with acceptable accuracy. A two-span continuous bridge is used to verify the method. The numerical results show that this method can identify the location of damage reasonably well.
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