This paper presents the results from a study on deterioration patterns of highway bridges, using estimated sojourn times bridge components in various states (condition). With emphasis age that leaves specified threshold condition state, uncertainties are best fitted as Weibull probability distribution functions. Using both complete observations' data and right-censored 13-year span historical for maximum likelihood estimates obtained parameters distributions, reliability analyses conducted...

The behavior and strength of welded shear studs are subjects ongoing study. A description the formulation American Institute Steel Construction specification provisions for is given. as influenced by friction, position in steel deck stud properties described. new model determination introduced compared with data from tests conducted authors well others.

In the proposed work, numerical simulations are conducted to investigate scissor-jack dampers for controlling vibrations in a seismically excited flexible truss tower. For damper, new equations developed model amplification factor that account large deformations of damper assembly. The validated using computer-aided design and used influence vertical on amplification. Then, seismic analysis is carried out installed 3D To reduce computational effort, bi-model method employed represent tower...

Barriers are purposely omitted from the structural analysis for bridge design or load rating. They not considered as primary members because, after a forceful collision, they may sustain some damage and would no longer strengthen deck. However, when completely intact, these secondary do affect distribution of applied loads, which is interest to permitting agencies, such Florida Department Transportation (FDOT). For prestressed concrete segmental box girder bridge, both rating (for oversized...

AbstractThis paper presents the results of impact tests on a roof system constructed with expanded metal mesh welded to steel frame. The was designed be installed masonry structure that will protect an emergency power generator at special-needs hurricane shelter during 177 km/h winds. and must meet windborne debris criteria for large missiles from ASTM Standards E1996-09 E1886-05, which state resist penetration by nominal 51×102 mm lumber plank weighing 4.08 kg traveling 54.7 km/h. Several...

Displacement measurements of structures like bridges are helpful in many ways. Understanding bridge response to increasing loads is interest analysis and load rating. Currently used direct displacement methods such as laser systems transducers expensive, time consuming difficult deploy, particularly on an in-service bridge. One indirect method would be use accelerometers obtain by directly integrating twice. Accelerometers inexpensive easy deploy; however noisy render a technique infeasible....

Concrete bridges in extremely aggressive environments deteriorate mainly from corrosion of carbon steel prestressing strands and rebars. In prestressed concrete girders, might occur the transverse reinforcement, which results a decrease shear resistance. Corrosion-free glass fiber reinforced polymer (GFRP) rebars corrosion-resistant stainless are promising solutions to address corrosion. However, GFRP have lower ultimate strain, elastic modulus, capacity than Two full-scale 12.8-m (42-ft)...

In the present work, numerical simulations are carried out to investigate a passive amplified structural damping system, scissor-jack damper, for controlling vibrations in seismically-excited truss tower. To reduce computational effort, bi-model method is employed represent 3D tower as dynamically equivalent 2D lumped-mass model. For new formulation amplification factor equation of device presented, and then validated using CAD. The accounts large deformations experienced by result...

Metal-plated wood truss systems may be rained upon during the construction phase, resulting in soaking of connections. In this paper, results an investigation behavior metal-plated joints subjected to periods are presented. The wetting regimes included (1) 4-h shower, (2) alternating cycles a period shower followed by no and (3) 24-h water tank. Results tests conducted after wet-dry were compared with dry control tests. show wet lost over 40% their load-carrying capacity all three regimes....

Measuring bridge displacement for moving vehicle loads helps in load rating and evaluating the structural health of bridge. Traditional methods measuring such as laser systems transducers are expensive, require a stationary reference point complicated to setup. acceleration using accelerometers is inexpensive easy. Displacement can be obtained from this acceleration, but due noise present measured direct double integration results erroneous estimations. In paper we use minimum description...

Stainless steel strands are a new technology and option available for the bridge industry. They have high corrosion resistance, which will result in more durable low-maintenance concrete bridges. However, stainless lower ductility different stress–strain behavior than carbon strands, affecting design criteria prestressed girders. already been deployed substructure components (piles) many projects around United States. due to their low lack of full-scale research studies structural...

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In the present article, gain matrix for active devices placed directly between masses on a truss tower is transformed at multiple levels masses. The gains are then used with single-mode approach to determine damper coefficients. Numerical validation of proposed method provided 3D single installed each level, and alternate configurations investigated. Damper in which least one located level concentrated result response that comparable optimal configuration.