Structures Under Crash and Impact

Hiermaier, Stefan

doi:10.1007/978-0-387-73863-5

Cited by 6 publications

(2 citation statements)

References 220 publications

(344 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The spalled debris has a momentum, which is caused by the impulse of the shock wave trapped between the free surface and the crack, minus the impulse of the restive forces of the concrete (McVay (1988)). A good overview of the theoretical background can be found in Meyers (1994) and Hiermaier (2008).…”

Section: Introductionmentioning

confidence: 99%

Secondary debris resulting from concrete slabs subjected to contact detonations

Hupfauf

Gebbeken

2022

Advances in Structural Engineering

View full text Add to dashboard Cite

As a consequence of terrorist attacks with explosives and malfunction of machinery detonations can lead to secondary debris on the protective side of a concrete wall. The term secondary debris in this context describes the debris resulting from a breakup of the loaded concrete structure in contrast to primary debris which results from the explosive or its casing. A test series has been conducted in order to investigate the physical phenomenology of the damaging process. A total of 15 reinforced concrete slabs with scaled thicknesses between 1.6 and 2.8 cm g−1/3 were loaded by contact detonations. The protective side of the concrete slabs was recorded with high-speed cameras during testing, and the damaged concrete slabs were measured with 3D-scans afterward. The acquired data will be evaluated for the velocity and mass of the secondary debris, to build the basis for an empirical model, which can make predictions about the occurring secondary debris. The objective of this paper is, to present the conducted experiments and propose the first part of an empirical model. This model predicts the geometry of the spalling crater on the protective side of the concrete slab, as well as the maximum velocity of the secondary debris. In following papers, the correlation between the mass and the velocity of the secondary debris will be derived from numerical simulations. With this, predictions can be made about the effects of the secondary debris on humans and installations on the protective side of the concrete slabs.

show abstract

Section: Introductionmentioning

confidence: 99%

Secondary debris resulting from concrete slabs subjected to contact detonations

Hupfauf

Gebbeken

2022

Advances in Structural Engineering

View full text Add to dashboard Cite

show abstract

“…The von Mises theory-based plasticity equations are no longer appropriate to characterize the phenomenology of inelastic polymer deformations due to the considerable stress variations. 26 Thus, more mechanical tests are required to calibrate advanced material models than the ordinary tensile test where shear test data could be introduced to describe non-linear plasticity. 27 Inducing pure shear stress state is impossible because of some of the undesirable side effects that occurred during the determination process.…”

Section: Introductionmentioning

confidence: 99%

In-plane shear and tensile behavior of two-pass injection-molded glass fiber reinforced polypropylene composites with different fiber lengths

Osama

Selmy

Abdelhaleem

et al. 2022

Journal of Composite Materials

View full text Add to dashboard Cite

Glass fiber reinforced polypropylene (GF-PP) composites have proven a great potential in the designation and manufacturing of control arms, leaf springs, barriers, beams and bridge decks. Two-pass injection molding of GF-PP was investigated in this study. Polypropylene (PP) was injected with different weight fractions (w%) of chopped glass fibers (GFs) with different fiber feedstock lengths (FFSLs). The composites were then crushed and re-injected once again. Some specimens were burned out to check the actual weight fractions and fiber lengths after the injection processes. The fiber lengths dramatically decreased due to damages during two-pass injection processes and crushing. The manufactured specimens were tested in tension, and the results indicated that the tensile strength increased slightly at w = 10% of GF. Further increase of GF weight fraction leads to a drop in the tensile strength below neat PP. The results of SEM micrographs showed an increase in air voids concentrations at high GF percentages which clarifies the reason behind the drop in the tensile strength. Also, in-plane shear tests were carried out using the Iosipescu fixture where a slight increase in the in-plane shear strength was noticed by increasing fiber weight fractions. In-plane shear moduli of all specimens were measured experimentally by strain gauges and calculated theoretically. The shear modulus was enhanced by glass fiber addition and a further increase was noticed by increasing the fiber weight fractions.

show abstract