Automotive Laminated Side Glazing Rollover Performance When Subjected to Roadway Abrasion and Occupant Loading

2019 ◽  
Author(s):  
Donald R. Phillips ◽  
Stephen A. Batzer
Keyword(s):  
Laminated Glass ◽  
Tempered Glass ◽  
Destructive Testing ◽  
Exterior Surface ◽  
Passenger Vehicles ◽  
Side Door ◽  
Pull Out ◽  
Retention Characteristics ◽  
Occupant Loading ◽  
Substantial Distance

Abstract Destructive testing of commercial automotive movable laminated side glass was conducted to document the occupant retention characteristics of this glazing system in quarter-roll crashes with a prolonged slide distance. That is, in some overturns a vehicle will slide to a halt on its side with a window adjacent both to an occupant’s position and to the moving roadway. It is known by field experience that this situation can result in injurious ejection of the occupant through the adjacent window if the window is constructed of tempered glass and the window has fractured. When tempered glass fractures, the window disintegrates and fully opens the portal. With the laminated side glazing that is used on some passenger vehicles, fracture of the inboard and outboard glass plies will not necessarily cause the “sandwiched” PVB interlayer to be compromised. This PVB interlayer allows the glass plies to remain in place and resist the sliding interaction. This diminishes the ejection hazard that is associated with tempered side glass. The three drag tests described within this technical paper used a single model of sport utility vehicle driver’s position door and factory installed laminated side door glass. The testing replicated the interaction of the exterior surface of the laminated glass against the moving roadway while the glazing was pre-fractured and the interior glass ply was subjected to significant simulated occupant loading. These conditions ensured contact of the exterior glass ply against the moving abrasive roadway. The detached and slightly modified driver’s door was pulled at near highway speed over a substantial distance against abrasive asphalt, simulating a rollover accident with the side of the vehicle sliding to halt. The results of these tests show that the exterior surface of the glazing, primarily consisting of the hard ceramic SiO2, is sufficiently wear resistant and durable to wear but not rupture or pull out of the peripheral channel. This testing shows that laminated glass is the superior glazing material for this accident mode from an occupant containment perspective.

Multi-performance blast pressure-duration curves of laminated glass panes

2020 ◽  
pp. 204141962096883
Author(s):  
Mohammadreza Eslami ◽  
Khalid M Mosalam ◽  
Venkatesh Kodur ◽  
Shalva Marjanishvili ◽  
Brian Katz ◽  
...  
Keyword(s):  
Blast Resistance ◽  
Design Procedure ◽  
Performance Criteria ◽  
Laminated Glass ◽  
Limit States ◽  
Performance Levels ◽  
Performance Pressure ◽  
Pull Out ◽  
Aspect Ratios ◽  
Ultimate Failure

The current design procedure for blast resistant glass panes is based on dynamic analysis of idealized SDOF models under simplified triangular impulse loads or code-specified pressure-duration (pressure-impulse) curves. In both cases, the main objective is to prevent failure of the pane with no explicit consideration of other limit states to reach higher performance levels. In this study, multi-performance pressure-duration curves of Laminated Glass (LG) panes are estimated by accurate pre-validated Finite Element (FE) models. Multiple performance criteria including initial cracking, PVB-50% (maximum polyvinyl butyral, i.e. PVB, interlayer strain of 50%), PVB-100% (maximum PVB interlayer strain of 100%), and ultimate failure of the pane are considered and pressure-duration curves are estimated for each of these performance levels. Ultimate failure of the pane can be either due to rupture of the PVB interlayer or pull-out of the pane from its frame. Multi-performance pressure-duration curves are obtained for 18 different LG panes with three different layups, two widths, and three aspect ratios. According to the obtained results, the thickness of the glass layers has more pronounced contribution to the blast resistance of the panes in all limit states compared with the PVB thickness. Moreover, the ultimate failure mode of the LG panes with thicker PVB interlayer is observed to be typically pull-out of the pane rather than PVB rupture. Therefore, these panes require frames with deeper bites to develop their full blast resistance. Finally, the blast performance of the LG panes are compared with that of Thermally Tempered Glass (TTG) panes to shed more light on the superior blast resistance of LG panes.

Finite Element Modeling of Electromagnetic Crimping of Cu-SS Tube-to-Tube Joint Along With Simulation of Destructive Testing for Strength Prediction of the Joint

2020 ◽  
Vol 143 (4) ◽  
Author(s):  
Deepak Kumar ◽  
Sachin D. Kore ◽  
Arup Nandy
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Compressive Strength ◽  
Element Model ◽  
Strength Prediction ◽  
Force Distribution ◽  
Radial Deformation ◽  
Destructive Testing ◽  
Pull Out ◽  
Element Method

Abstract This work explores the tube-to-tube joining of copper (outer) and stainless steel (inner) using electromagnetic crimping. Stand-off distance is kept constant during all the experiments. ls-dynaTM electromagnetic module, which utilizes finite element method combined with the boundary element method, is used to perform numerical simulations and the model is validated with experimentally observed thinning and radial deformation of the outer tube during electromagnetic crimping. Effect of slit of the field shaper on Lorentz force distribution is studied. It is observed that the slit of the field shaper leads to uneven radial deformation. Furthermore, a novel finite element model has been developed to predict the pull-out and compressive strength of the joint. Results are validated with the experimentally observed data.

A Novel Technique for Measuring Pedicle Screw Forces In Situ

2008 ◽  
Author(s):  
Samuel Q. Tia ◽  
Jennifer M. Buckley ◽  
Thuc-Quyen Nguyen ◽  
Jeffrey C. Lotz ◽  
Shane Burch
Keyword(s):  
Pedicle Screw ◽  
Pedicle Screws ◽  
Clinical Failure ◽  
Strain Gages ◽  
Destructive Testing ◽  
Novel Technique ◽  
Pull Out ◽  
Pull Out Strength

Long posterior fusion constructs in the lumbar spine cause substantial posteriorly directed loading of the supporting pedicle screws, particularly during patient bending activities. Although there are numerous documented accounts of clinical failure at the pedicle screw-bone interface [1,2], the in situ pull-out strength of pedicle screws in long surgical constructs has not been characterized. Previous biomechanical studies have quantified pedicle screw pull-out force in cadaveric models through destructive testing or in nondestructive cases, through the use of custom-machined pedicle screws instrumented with strain gages [3–6]. However, these techniques involve altering screw geometry and may fail to properly simulate in vivo mechanical loading conditions. The goal of this study was to develop and validate a sensor system for measuring pedicle screw pull-out forces in long posterior constructs in situ during multi-segmental cadaveric testing.

Motor Coach/Bus Crashworthiness Systems: Occupant Retention

2009 ◽  
Author(s):  
Stephen A. Batzer ◽  
David Beltran ◽  
G. Grant Herndon ◽  
Chandrashekhar K. Thorbole ◽  
Mariusz Ziejewski
Keyword(s):  
Laminated Glass ◽  
Restraint System ◽  
Destructive Testing ◽  
Body Forces ◽  
Physical Testing ◽  
Feasible Solutions ◽  
Energy Absorbing ◽  
Objective Being

Destructive testing of the complete motor coach/bus restraint system to include seatbelts, side glazing, and greenhouse structure was performed with the objective being to determine the overall rollover crashworthiness in this accident mode. During motor coach/bus rollovers, the roof and pillar structures may deform due to friction and body forces initiated by ground and roadway contact. Body deformation, as well as interaction of the glass with rocks and other debris on the ground and roadway, may lead to catastrophic glazing failure, opening a portal for occupant partial or complete ejection. Despite the relatively high occupant capacity of motor coaches/buses, many commercial designs provide seatbelt restraints only for the purpose of securing wheelchairs and the driver, providing no seatbelt restraints for occupants in passenger positions. Rollover testing was performed on a modified commuter motor coach/bus to determine the effectiveness of the seatbelts as primary restraints, and also on several energy absorbing window designs to determine their efficacy as secondary restraints. The results showed that properly fixated laminated glass and other designs were capable of fully retaining both belted and unbelted occupants during the staged collision. This testing showed that structural roof members and occupant retention glazing systems are feasible solutions for the purpose of occupant retention. The physical testing was complemented by simulations of this accident showing that the loading received by the occupants is not injurious.

scholarly journals Laminated Glass Cantilevered Plates under Static and Impact Loading

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Luigi Biolzi ◽  
Antonio Bonati ◽  
Sara Cattaneo
Keyword(s):  
Finite Element ◽  
Stress Distribution ◽  
Impact Loading ◽  
Structural Performance ◽  
Laminated Glass ◽  
Finite Element Analyses ◽  
Tempered Glass ◽  
Low Velocity ◽  
Glass Plates ◽  
Experimental Findings

The structural performance of cantilevered laminated glass plates for different glass thicknesses and interlayers is considered in this paper. Heat-strengthened and tempered glass plies and two different interlayer films were utilized. The response of laminated glass specimens is then evaluated under low-velocity hard and semirigid impacts. Experimental findings were simulated and discussed by means of finite element analyses. In particular, this discussion includes the evaluation of the influence that the fixed edge clamping technique (number of clamps, their size, and their stiffness) has on the stress distribution in the specimens.

Mechanical and Dynamic Characteristics of Laminated Glass Sheets Used for Staircases

2014 ◽  
Vol 601 ◽  
pp. 227-230
Author(s):  
Cristian Lucian Ghindea ◽  
Dan Cretu ◽  
Radu Cruciat ◽  
Ovidiu Bogdan
Keyword(s):  
Mechanical Characteristics ◽  
Experimental Tests ◽  
Laminated Glass ◽  
Deformation Capacity ◽  
Test Results ◽  
Dynamic Tests ◽  
Tempered Glass ◽  
Successful Design ◽  
Strength And Deformation ◽  
Static And Dynamic Tests

In case of laminated glass strips, the mechanical characteristics of the composite element are different from the values that are obtained for the same element from a homogeneous and isotropic material. The experimental tests presented in the paper aims to determine the mechanical characteristics of laminated glass strips used to make a staircase. For the experiment, quasi-static and dynamic tests were conducted on different glass stair steps, made from normal and tempered glass, with different number and thicknesses glass sheets. The paper presents the carrying out conditions for the experiments, the synthesis of data processing and comments on the experimental results. Experimental test results led to the constructive solution of the glass staircase steps. For staircase building up, tempered glass was chosen and the values obtained for the mechanical properties, strength and deformation capacity of the system were used in its design. Whole set of experimental tests led to a successful design and build-up of the glass staircase.

Contrast of a Probabilistic Design Model for Laminated Glass Plates

2012 ◽  
Vol 730-732 ◽  
pp. 501-506 ◽  
Author(s):  
María Jesús Lamela ◽  
Alfonso Fernández Canteli ◽  
Constanze Przybilla ◽  
Mónica Menéndez
Keyword(s):  
Cumulative Distribution Function ◽  
Polyvinyl Butyral ◽  
Ceramic Materials ◽  
Design Model ◽  
Cumulative Distribution ◽  
Laminated Glass ◽  
Probabilistic Design ◽  
Tempered Glass ◽  
Micro Cracks ◽  
Glass Plates

As other ceramic materials, glass presents a brittle behaviour and a broad scatter of strength results, due to the random distribution of micro-cracks on its surface. On the other hand, the specific properties of glass and Polyvinyl Butyral (PVB) are combined in laminated glass, resulting in a viscoelastic behaviour for the whole assembly. In this paper, a probabilistic design model is proposed for laminated glass plates of annealed and tempered glass, taking into account the time-dependent properties of the PVB interlayer and the glass characterization by means of a three-parameter Weibull cumulative distribution function of critical stresses. To validate the model proposed, an experimental programme was carried out using laminated glazing of 1.4 m x 1.4 m, varying the kind of glass, thickness and boundary conditions.

scholarly journals Structural performance of a novel liquid-laminated embedded connection for glass

2021 ◽  
Author(s):  
Efstratios Volakos ◽  
Chris Davis ◽  
Martien Teich ◽  
Peter Lenk ◽  
Mauro Overend
Keyword(s):  
Structural Integrity ◽  
Load Transfer ◽  
Mechanical Response ◽  
Maximum Load ◽  
Structural Performance ◽  
Laminated Glass ◽  
Promising Alternative ◽  
Load Bearing ◽  
Pull Out ◽  
Novel Variant

AbstractConnections between load-bearing glass components play a major role in terms of the structural integrity and aesthetics of glass applications. Recently, a new type of adhesive connection, known as embedded laminated glass connections, has been developed where a metallic insert is embedded within a laminated glass unit by means of transparent polymeric foil interlayers and assembled through an autoclave lamination process. In this study, a novel variant of this connection, consisting of a thin steel insert encapsulated by a transparent cold-poured resin, is proposed and examined. In particular, the axial tensile mechanical response of this connection is assessed via numerical (FE) analyses and destructive pull-out tests performed on physical prototypes at different displacement rates in order to assess the effect of the strain rate-dependent behaviour of the resin interlayer. It was found that the pull-out stiffness, the maximum load-bearing capacity and the failure mode of the connection are significantly affected by the imposed displacement rate. The numerical (FE) analysis of the pull-out tests, performed in Abaqus, showed that the complex state of stress in the vicinity of the connection is the result of two load-transfer mechanisms and that the relative contribution of these mechanisms depends on the insert geometry and the relative stiffnesses of the constituent materials. Overall, it is concluded that the prototypes are promising in terms of manufacturability, aesthetics and structural performance and thus the novel variant connection considered in this study offers a promising alternative to existing load-bearing connections for laminated glass structures, but further investigations are required to ascertain its suitability for real-world applications.

Impact-resistant nacre-like transparent materials

Science ◽  
2019 ◽  
Vol 364 (6447) ◽  
pp. 1260-1263 ◽  
Author(s):  
Z. Yin ◽  
F. Hannard ◽  
F. Barthelat
Keyword(s):  
Impact Resistance ◽  
Three Dimensional ◽  
High Strength ◽  
Thermoplastic Elastomer ◽  
Laminated Glass ◽  
Tempered Glass ◽  
Sliding Mechanism ◽  
Brick And Mortar ◽  
Strength And Stiffness ◽  
Nonlinear Deformations

Glass has outstanding optical properties, hardness, and durability, but its applications are limited by its inherent brittleness and poor impact resistance. Lamination and tempering can improve impact response but do not suppress brittleness. We propose a bioinspired laminated glass that duplicates the three-dimensional “brick-and-mortar” arrangement of nacre from mollusk shells, with periodic three-dimensional architectures and interlayers made of a transparent thermoplastic elastomer. This material reproduces the “tablet sliding mechanism,” which is key to the toughness of natural nacre but has been largely absent in synthetic nacres. Tablet sliding generates nonlinear deformations over large volumes and significantly improves toughness. This nacre-like glass is also two to three times more impact resistant than laminated glass and tempered glass while maintaining high strength and stiffness.

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