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This laboratory study aims to investigate curing and thermal effect on mechanical properties of mortar produced with waste rubber as fine aggregate. For this purpose, three type of rubber content was used in mix design like 0%, 10% and 20%. Mortar specimens were produced with 520 kg cement. The type of used cement is CEM I 42.5 R ordinary Portland cement and w/c ratio were kept at 0.485 level at all mix design. Rilem sand was used in the mortar. Rolled crumb waste rubber was used in the composition and the grain size of used waste rubber was between 1-4 mm. The effect of curing age was evaluated on compressive strength and abrasion resistance on the base of three distinct rubber content. Moreover, the compressive strength results were evaluated with two different temperature levels, i.e. 150 0 C and 200 0 C and three different curing age condition, i.e. 3 days, 7 days and 28 days. As a result, it was observed that there is a constant decrease at early curing age of mortar in terms of compressive strength, but there is a sharp decrease at 28-days curing condition. As for abrasion resistance, it was determined that abrasion loss was increased in the early curing age of specimens. However, abrasion loss was decreased with increasing rubber content.

An earthquake with a magnitude ranging from Mw = 6.9 (KOERI) to Mw = 7.0 (USGS) struck Samos Island in the Aegean Sea on October 30, 2020, with an epicentre 70 kms from the İzmir city centre in Turkey. The earthquake took place at 14:51 local time (11:51 UTC). The peak ground acceleration (PGA) of this earthquake was recorded to be 0.179 g at the epicentre of the earthquake. This earthquake occurred at a depth of 17.26 km (AFAD (2020) İzmir Earthquake Report, (In Turkish)) and lasted 16 s. The main shock from the earthquake triggered a tsunami that hit the building stocks built near the coast. During the gradual deregulation of COVID-19 pandemic regulations, various events caused considerable damage to the building stock, particularly in the Izmir Seferihisar and Bayraklı regions and resulted in a massive disruption of daily habits. The main shock caused 117 deaths in both Turkey and Greece, and 1632 people were also injured in Turkey. Moreover, several injuries occurred in Greece. A total of 103 buildings collapsed, 700 were severely damaged, 814 buildings were moderately damaged, and 7889 were slightly damaged. The basic aim of this paper is to briefly present the past and present seismotectonic characteristics of the region, present building stock, and former structural conditions before the earthquake, assess structural performance and classify distinguished earthquake-induced failures and damage due to the basin effect.

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In the studies carried out until today, rubber-modified self-compacting concretes (RMSCC) had been manufactured by replacing the aggregates of the waste vehicle tires (WVT) in the grain size distribution and particles that have different workability, different mechanical, and physical properties. However, variation of the carrying capacity of the RMSCC elements produced with different slenderness ratio h/b ratio under axial load had not been researched in previous studies. Within the scope of this study, the change in physical and mechanical properties of RMSCC elements produced by using different h/b ratios had been examined both experimentally and theoretically. Since the natural sand and WVT aggregate used in the production of concrete and their grain sizes are in the same range, WVT aggregate has been replaced by natural sand in 4 different proportions. These ratios were used as 5%, 10%, 15% and 20% of the natural sand volume, respectively. Slenderness ratios, h/b ratios were 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5, and experimental and theoretical investigations had been performed for 90 samples in total. The linear regression models of the obtained results had been analyzed and the equations with the h/b ratios according to these models had been produced. The results of the obtained equations and the results of experimental axial pressure had been compared. In addition to the amount of WVT aggregate used and the increase in the ratio of h/b, the compressive strength losses had caused by different rates on the samples. The effect of the WVT aggregate ratio on the compressive strength had become more significant with the increase in use rate. Besides, regression analyzes had been performed to determine the effect of h/b ratio on the compressive strength. In conclusion, regression R 2 (coefficient of determination) values that belong to equations obtained had been found over 0.95.