scholarly journals Field Evaluation of Load Bearing Capacity and Embedment Depth of Existing Ballastless Plate Girder Bridge Foundations

2021 ◽  
Vol 21 (1) ◽  
pp. 225-230
Author(s):  
Hyeonwoo Yoo ◽  
Jeongho Oh ◽  
Sinwhan Ahn
Keyword(s):  
Bearing Capacity ◽  
Embedment Depth ◽  
Penetration Test ◽  
Bridge Foundations ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Girder Bridge ◽  
Unknown Foundations ◽  
Unknown Foundation ◽  
Plate Girder

The ballastless plate girder bridge, classified as a structure type that requires an emergent replacement among domestic railway bridges, generally tends to upgrade to a ballasted track along with continuous welded rail (CWR). The axial forces of the CWR due to the temperature change need to be distributed to the bridge foundations. Because most of the existing ballastless plate girder bridges of over 50 years of age do not provide any design information, such bridge foundations are regarded as unknown foundations, and therefore, it is crucial to identify the structural adequacy and dimension. In this study, an effort was made to establish a correlation between the standard penetration test (SPT) and mid-size pneumatic cone penetration test (MPCP) to estimate the load bearing capacity of an unknown foundation. A field test was conducted to estimate the depth of the unknown foundation by employing SPT and MPCP as the source wave part. The magnitude of the shear wave was mitigated by the presence of PVC and steel pipes, such that it might be possible to identify the embedment depth of unknown foundations.

Study on Diseases of Multi-Box Girder Bridge

2012 ◽  
Vol 446-449 ◽  
pp. 1182-1185
Author(s):  
Wen Liang Qiu ◽  
Cai Liang Huang ◽  
Zhao Yi Chen
Keyword(s):  
Bearing Capacity ◽  
Box Girders ◽  
Load Bearing Capacity ◽  
Box Girder ◽  
Load Bearing ◽  
Large Load ◽  
Torsion Rigidity ◽  
Box Girder Bridge ◽  
Girder Bridge ◽  
Design And Construction

Because the multi-box girder bridge has many advantages, such as large torsion rigidity, large load-bearing capacity, stability, fine appearance, good applicability and convenient construction, it is widely used in China. But for the defection existing in design and construction, many box girders have serious diseases. Aiming at the diseases of a viaduct bridge, the causes of diseases are analyzed and the enforcement method is proposed in this paper. The study shows that, though the box girders have large torsion rigidity, the diaphragms are designed necessarily to enhance the transversal connection between the box girders, to make them bear the loads together, to reduce their stresses and deformation, and to reduce the stresses of deck too.

scholarly journals Numerical evaluation of the plastic hinges developed in headed stud shear connectors in composite beams with profiled steel sheeting

2018 ◽  
Author(s):  
Valentino Vigneri ◽  
Christoph Odenbreit ◽  
Matthias Braun
Keyword(s):  
Bearing Capacity ◽  
Numerical Evaluation ◽  
Composite Beams ◽  
Shear Capacity ◽  
Embedment Depth ◽  
Shear Connector ◽  
Load Bearing Capacity ◽  
Plastic Hinges ◽  
Load Bearing ◽  
Headed Stud

For composite beams using novel steel sheeting, the current Eurocode 4 rules sometimes overestimate the load bearing capacity of the shear connector. This is due to the larger rib heights and the smaller rib widths in comparison with the old studies, which have been carried out to calibrate the current design equations. The RFCS Project “DISCCO” investigated this phenomena and the working group under mandate M515, CEN/TC250/SC4/SC4.T3 is enhancing this equation and working on a proposal to be taken over in the new version of Eurocode 4.The proposed new equation covers the failure behaviour of the shear connection more in detail. The test results show, that the failure consists in a combined concrete cone and stud in bending. Due to the geometry of novel steel sheeting, the load bearing capacity of the headed stud shear connector is no more limited by its shear capacity, but by its bending capacity.A 3D non-linear finite element model is developed and validated through the support of the DISCCO push-out tests. A good agreement between numerical and experimental results in terms of force-slip behaviour is achieved. Special attention of this work lies on the numerical evaluation of the number of plastic hinges ny: a stress-based procedure is presented and the results are compared to the equations presented for new Eurocode 4.The numerical simulations show that the upper plastic hinge moves up as the slip increases due to the progressive crushing of the concrete in the rib. From the parametric study, it turns out that ny is linearly proportional to the embedment depth. Compared to pre-punched hole decking, through-deck welding specimen activates less plastic hinges in the studs because of the higher stiffness provided at the base of the stud.

Increased load bearing capacity of mechanically joined FRP/metal joints using a pin structured auxiliary joining element

2020 ◽  
Vol 62 (1) ◽  
pp. 55-60
Author(s):  
Per Heyser ◽  
Vadim Sartisson ◽  
Gerson Meschut ◽  
Marcel Droß ◽  
Klaus Dröder
Keyword(s):  
Bearing Capacity ◽  
Load Bearing Capacity ◽  
Load Bearing

Load-Bearing Capacity of Direct Inlay-Retained Fibre-reinforced Composite Fixed Partial Dentures with Different Cross-Sectional Pontic Design

2017 ◽  
Vol 68 (1) ◽  
pp. 94-100
Author(s):  
Oana Tanculescu ◽  
Adrian Doloca ◽  
Raluca Maria Vieriu ◽  
Florentina Mocanu ◽  
Gabriela Ifteni ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Fracture Pattern ◽  
Load Bearing Capacity ◽  
Cross Sectional ◽  
Load Bearing ◽  
Reinforced Composite ◽  
Polyethylene Fibre

The load-bearing capacity and fracture pattern of direct inlay-retained FRC FDPs with two different cross-sectional designs of the ponticwere tested. The aim of the study was to evaluate a new fibre disposition. Two types of composites, Filtek Bulk Fill Posterior Restorative and Filtek Z250 (3M/ESPE, St. Paul, MN, USA), and one braided polyethylene fibre, Construct (Kerr, USA) were used. The results of the study suggested that the new tested disposition of the fibres prevented in some extend the delamination of the composite on buccal and facial sides of the pontic and increased the load-bearing capacity of the bridges.

scholarly journals The energy absorption behavior of novel composite sandwich structures reinforced with trapezoidal latticed webs

2021 ◽  
Vol 60 (1) ◽  
pp. 503-518
Author(s):  
Juan Han ◽  
Lu Zhu ◽  
Hai Fang ◽  
Jian Wang ◽  
Peng Wu
Keyword(s):  
Bearing Capacity ◽  
Energy Absorption ◽  
Sandwich Structure ◽  
Ultimate Load ◽  
Sandwich Structures ◽  
Elastic Displacement ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Composite Sandwich ◽  
Composite Sandwich Structures

Abstract This article proposed an innovative composite sandwich structure reinforced with trapezoidal latticed webs with angles of 45°, 60° and 75°. Four specimens were conducted according to quasi-static compression methods to investigate the compressive behavior of the novel composite structures. The experimental results indicated that the specimen with 45° trapezoidal latticed webs showed the most excellent energy absorption ability, which was about 2.5 times of the structures with vertical latticed webs. Compared to the traditional composite sandwich structure, the elastic displacement and ultimate load-bearing capacity of the specimen with 45° trapezoidal latticed webs were increased by 624.1 and 439.8%, respectively. Numerical analysis of the composite sandwich structures was carried out by using a nonlinear explicit finite element (FE) software ANSYS/LS-DYNA. The influence of the thickness of face sheets, lattice webs and foam density on the elastic ultimate load-bearing capacity, the elastic displacement and initial stiffness was analyzed. This innovative composite bumper device for bridge pier protection against ship collision was simulated to verify its performance. The results showed that the peak impact force of the composite anti-collision device with 45° trapezoidal latticed webs would be reduced by 17.3%, and the time duration will be prolonged by about 31.1%.

scholarly journals Constructing a biomimetic robust bi-layered hydrophilic lubrication coating on surface of silicone elastomer

Friction ◽  
2021 ◽  
Author(s):  
Luyao Gao ◽  
Xiaoduo Zhao ◽  
Shuanhong Ma ◽  
Zhengfeng Ma ◽  
Meirong Cai ◽  
...  
Keyword(s):  
Bearing Capacity ◽  
Composite Layer ◽  
High Load ◽  
Silicone Elastomer ◽  
Aqueous Lubrication ◽  
Low Friction ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Lubrication Performance ◽  
Wide Range

AbstractSilicone elastomers-based materials have been extensively involved in the field of biomedical devices, while their use is extremely restricted due to the poor surface lubricity and inherent hydrophobicity. This paper describes a novel strategy for generating a robust layered soft matter lubrication coating on the surface of the polydimethylsiloxane (PDMS) silicone elastomer, by entangling thick polyzwitterionic polyelectrolyte brush of poly (sulfobetaine methacrylate) (PSBMA) into the sub-surface of the initiator-embedded stiff hydrogel coating layer of P(AAm-co-AA-co-HEMA-Br)/Fe, to achieve a unified low friction and high load-bearing properties. Meanwhile, the stiff hydrogel layer with controllable thickness is covalently anchored on the surface of PDMS by adding iron powder to provide catalytic sites through surface catalytically initiated radical polymerization (SCIRP) method and provides high load-bearing capacity, while the topmost brush/hydrogel composite layer is highly effective for aqueous lubrication. Their synergy effects are capable of attaining low friction coefficient (COFs) under wide range of loaded condition in water environment with steel ball as sliding pair. Furthermore, the influence of mechanical modulus of the stiff hydrogel layer on the lubrication performance of layered coating is investigated, for which the COF is the lowest only when the modulus of the stiff hydrogel layer well matches the PDMS substrate. Surprisingly, the COF of the modified PDMS could remain low friction (COF < 0.05) stably after encountering 50,000 sliding cycles under 10 N load. Finally, the surface wear characterizations prove the robustness of the layered lubricating coating. This work provides a new route for engineering lubricious silicon elastomer with low friction, high load-bearing capacity, and considerable durability.

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