The mechanical properties of Polyvinyl Butyral (PVB) at high strain rates

Abstract

h i g h l i g h t sLow-speed and high-speed direct tensile tests were performed on PVB material. Stress-strain curves were derived at strain rates from 0.008 s À1 to about 1360 s À1 . The strength was found to increase with strain rate; but PVB becomes less ductile. The testing results with available testing data were summarized and analyzed. a b s t r a c tPolyvinyl Butyral (PVB) has been largely used as an interlayer material for laminated glass to mitigate the hazard from shattered glass fragments, due to its excellent ductility and adhesive property with glass pane. With increasing threats from terrorist bombing and debris impact, the application of PVB laminated safety glass has been extended from quasi-static loading to impact and blast loading regimes, which has led to the requirement for a better understanding of PVB material properties at high strain rates. In this study, the mechanical properties of PVB are investigated experimentally over a wide range of strain rates. Firstly, quasi-static tensile tests is performed using conventional hydraulic machine at strain rates of 0.008-0.317 s À1 . Then high-speed tensile test is carried out using a high-speed servo-hydraulic testing machine at strain rates from 8.7 s À1 to 1360 s À1 . It is found that under quasi-static tensile loading, PVB behaves as a hyperelastic material and material property is influenced by loading rate. Under dynamic loading the response of PVB is characterized by a time-dependent nonlinear elastic behavior. The ductility of PVB reduces as strain rate increases. The testing results are consistent with available testing data on PVB material at various strain rates. Analysis is made on the testing data to form strain-rate dependent stress-strain curves of PVB under tension.

Determining Material Response for Polyvinyl Butyral (PVB) in Blast Loading Situations

“…Therefore, it is possible that this parameter might increase further should the material be deformed at higher rates. This further increase was also confirmed in the newer data produced by Zhang et al [11].…”

“…Whilst photoleasticity results showed that the strains were uniformly distributed after the very initial sample loading stage, Hooper et al [12] calculated that for the 400 s case, the rise time predicted with an assumed initial stiffness would be similar to the time taken by a stress wave to travel the length of the sample, 40 μs, prejudicing the exact stiffness measurement in the early times. Zhang et al [11] however measured longer initial yield times with a similar set up and material. This suggested the initial results were valid, as suggested here by the photoelasticity results shown in Fig.…”

“…They then fitted the data with multiple individual material laws to cover the different rates and stress regimes [10]. Recently, Zhang et al [11] also performed high rate tests on the PVB material, reaching rates beyond 1000 s…”

The response of glass window systems to blast loadings: An overview

“…Williams-Landel-Ferry equation to shift shear modulus of different temperatures [76]. The mechanical behavior of PVB at large strain was studied at both quasi-static and dynamic states [54,[76][77][78][79][80]. Laboratory tests reveal that PVB shows viscoelastic material properties at low strain rates and is loading rate dependent.…”

Response of Coated Laminated Glass Panels Subjected to Combined Blast and Temperature Loadings

“…The authors concluded that LSG panels should be designed to fail by tearing of the interlayer rather than failure at the supports to achieve a desired level of protection. Many researchers have studied the dynamic properties of glass [18,19] and PVB materials [20,21] to help design better glass resistant panels.…”