We present details on the timing of glaciations during the late Quaternary in the western Taurus Mountain Range of Turkey. Twenty‐five boulders from prominent moraines in three northern glacial valleys of Mount Dedegöl (37.40°N, 31.17°E, 2992 m above sea level, ∼15 km west of Lake Beyşehir) were dated based on cosmogenic 36Cl surface exposure. The geomorphological mapping of the N‐NE‐trending Sayacak, Kisbe and Karagöl valleys and their in situ produced 36Cl glacial chronology revealed several glacial episodes during the late Quaternary from (pre‐Last Glacial Maximum (pre‐LGM) to early Holocene. Pre‐LGM glaciations are represented by a push‐hummocky moraine complex in the northern Sayacak Valley and dated to 29.7 ± 2.9 ka. The ages obtained from these hummocky moraines give substantial evidence regarding ice accumulation before the global LGM. In the same valley, glaciers reached their maximum positions at the LGM and deposited lateral moraines at 19.7 ± 1.6 ka. Lateglacial moraines were dated to between 16.4 ± 0.7 and 12.0 ± 1.0 ka in the nearby east‐facing Karagöl valley. The youngest glacial stages occurred during the Younger Dryas stadial (11.5 ± 0.8 ka) and early Holocene (9.8 ± 1.4 ka) in Mount Dedegöl.

Abstract The dynamic fracture behavior of brittle materials that contain micro-level cracks should be examined when material subjected to impact loading. We investigated the effect of micro-cracks on the propagation of macro-cracks that initiate from notch tips in the Kalthoff-Winkler experiment, a classical impact problem. To define pre-defined micro-cracks in three-dimensional space, we proposed a two-dimensional micro-crack plane definition in the bond-based Peridynamics (PD) that is a non-local form of classical continuum theory. Randomly distributed micro-cracks with different number densities in a constant area and number in expending area models were examined to monitor the toughening of the material. The velocities of macro-crack propagation and the time required for completing of fractures were considered in several pre-defined micro-cracks cases. It has been observed that toughening mechanism only initiated by exceeding a certain number of micro-cracks; therefore, there is a positive correlation between the density of pre-defined micro-cracks and macro-crack propagation rate and also, toughening mechanism.

It has been seen that Cylindrical Type Instantaneous Safety Gear, which is one of the most important element of an elevator system, during safety gear operation is being exposed to high stresses and brake accelerations. The stress and deformation distribution of a cylindrical type safety gear’s brake block was investigated using finite elements and experimental methods. Results found with FEM by using ABAQUS/CAE software were compared to experimental results. It is clearly seen that the element type and boundary conditions used in finite element modelling give satisfactory results.

Dynamic crack propagation assessment in functionally graded materials (FGMs) with micro-cracks is accomplished using bond-based Peridynamics (PD). The dynamic fracture behaviour of various FGMs' material models is studied in Kalthoff-Winkler experiment. Dynamic crack growth predictions and associated material damage of the specimen under dynamic loading conditions are considered. The effect of micro-cracks near macro-crack tips on the toughening mechanism is evaluated in terms of crack propagation velocities. Stochastically pre-located micro-cracks are modelled to obtain the toughening effect in the material. Additionally, the velocities and time required for fracture are compared in different FGM cases. It is frankly found that if a crack propagates in the harder region of the specimen, velocities decrease and toughness increase in contrast to the softer region. Furthermore, micro-cracks around a macro-crack decelerate the crack propagation and enhance toughening mechanism in FGM body depending on gradation of material properties.

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