The protection of historic masonry structures against earthquakes is only possible by accurately assessing their non-linear behaviour, in particular their potential for severe damage and collapse. Experimental investigations on historic structures can be damaging, time consuming and costly. Therefore, in recent years, numerical modelling and analysis techniques have become common and reliable methods for determining the structural behaviour of historic structures. Turkey, which is located in a seismic zone, is home to many historical and cultural heritage sites. This study investigates the seismic performance of the historic Durak Han, located in the Durağan district of Sinop province due to its proximity to the North Anatolian Fault Line. The inn has been heavily damaged due to careless use and earthquakes and has been repaired many times. The seismic behaviour, force-displacement capacity and collapse mechanism of the stone vaulting have been investigated. A numerical simulation method had never been applied to the inn before. A comprehensive finite element model was constructed based on the architectural survey projects of the inn and this model was corrected using the experimental modal analysis results available in the literature. In order to determine the seismic behaviour and collapse mechanisms of the inn, nonlinear dynamic analyses were performed using the ground motion records of the 2023 Kahramanmaraş earthquakes. The maximum principal stresses, maximum displacements and damage distributions of the inn were evaluated.

En tr Geosynthetics; Geotextile, geomembrane, geonet, geocomposite and similar products are materials that provide the functions of natural building materials (sand, gravel, clay, etc.). Developments in the production network have increased the use of geosynthetics in the construction sector. Geosynthetics are widely used in deep excavation and road projects. In geotechnical engineering, geosynthetics are used especially in solving slope stability problems. The high stresses and deformations resulting from the stability losses of the slopes have led the engineers to develop slope reinforcement systems. In this study, geotextile was used in order to affect long term behavior of slope stability and to counter the underground water level. Samples both with and without geotextiles with the same slope angle were resolved by limit equilibrium method in the study. In each analyzes, the ground deformation and factor of safety were compared. The contribution of geotextiles to increasing bearing capacity of soil is emphasized. Geosentetik; geotekstil, geomembran, geonet, geokompozit ve buna benzer ürünler, doğal yapı malzemelerinin (kum, çakıl, kil vb…) gördüğü işlevleri sağlayan malzemelerdir. Üretim ağındaki gelişmeler, inşaat sektöründe geosentetik kullanım alanlarını arttırmıştır. Geosentetiklerin, derin kazı ve yol projelerinde kullanım alanları oldukça yaygındır. Geoteknik mühendisliğinde geosentetikler özellikle şev stabilitesi problemlerinin çözülmesinde kullanılmaktadır. Şevlerin stabilite kayıpları sonucunda oluşan yüksek gerilme ve deformasyonlar mühendisleri şev güçlendirme sistemleri geliştirmeye yönlendirmiştir. Şev stabilitesinin uzun dönemdeki davranışını etkilemek ve yer altı su seviyesine karşı koymak amacıyla bu çalışmada geotekstil kullanılmıştır. Çalışmada, aynı şev açılarına sahip geotekstil kullanılan ve kullanılmayan örnekler limit denge yöntemi ile çözümlenmiştir. Her iki analizde meydana gelen zemin deformasyonları ve güvenlik katsayıları karşılaştırılmıştır. Geotekstillerin zemin taşıma gücünün artırılmasına olan katkısı vurgulanmıştır.

On 6 February 2023, two major earthquakes struck southeastern Türkiye along the East Anatolian Fault, causing widespread structural damage, including the partial collapse of the historic Habibi Neccar Mosque in Antakya. This study presents a simulation-based approach to rapidly assess the seismic vulnerability of this partially damaged historic masonry structure. Due to the complexity and urgent condition of such heritage buildings, a simplified finite element (FE) modeling methodology is employed to evaluate structural behavior and support immediate stabilization decisions. Response spectrum analysis is applied to simulate and interpret stress distribution and deformation patterns in both undamaged and damaged states. The simulation results highlight significant tensile stress concentrations exceeding 0.2 MPa at dome–arch joints and vaults—primary indicators of localized failures. Additionally, the analysis reveals increased out-of-plane deformations and the influence of soil amplification in the remaining walls, both of which further compromise the structural integrity of the building. The findings demonstrate that simplified FE simulations can serve as practical and efficient tools for early seismic assessment of historic structures, contributing to rapid decision making, risk mitigation, and cultural heritage preservation in earthquake-prone areas.

Uygarlıkların tanıkları ve medeniyetlerin yansımalarını günümüze taşıyan tarihi yapıların bir kısmı zamanın ve bu zaman diliminde meydana gelen tüm olumsuz etkilere yenik düşmüş, bir kısmı ise günümüze hala ışık tutmaktadır. Asırlara meydan okuyan kale tipi tarihi strüktür örnekleri; genel olarak diğer tip yapılardan farklı formda ve amaçta inşa edilmişlerdir. İnşa edilme nedenleri doğrultusunda diğer yapılardan daha ağır ve daha dayanıklı oldukları bilinmektedir. Bir form ile ifade edilen cami, kilise, köprü gibi tarihi yapılarda genel olarak sütun, kiriş, tonoz, kubbe, kemer gibi strüktür elemanları bulunmaktadır. Bu tip yapıların yapısal davranışları hakkında genel olarak yapısal davranış teorileriyle yorum yapmak daha kolaydır. Fakat kale gibi ağır kütleli ve belirli, düzenli bir forma sahip olmayan yapıların, strüktürel davranışları hakkında yorum yaparken mühendisliğin temel prensipleri doğrultusunda sistematik bir şekilde ilerlemek gerekmektedir. Bu makale de amaç; kale tipi ağır kütleli yapıların sonlu elemanlar hesap yöntemiyle çevresel etkiler altında yapısal dengesinin sistematik bir şekilde yorumlanmasıdır. Sonlu elemanlar modellemesinde üç temel burç formu olan dörtgen, altıgen ve dairesel geometriye sahip burç örnekleri SAP 2000 sonlu elemanlar paket programında modellenmiştir. Bu üç formun zamana bağlı malzeme kaybının yapı üzerindeki etkileri, kademeli lineer statik analizlerle incelenmiştir.

Turkey is a country that has hosted many civilizations due to its geographical location. The artefacts of these civilizations constitute important historical heritages of the country. The preservation, restoration and strengthening of historical artefacts and their transfer to future generations are the responsibilities of every country. Historical Sinop Castle that investigated in this study locates in the Sinop city where takes place northernmost of Turkey. Sinop province is a half island due to its geographical position and it is known that the castle walls were built due to the protection of this city. It is not known exactly when the historic Sinop Castle was built. It is estimated the time period of built could be 8th century B.C based on excavations. It is known that to hosted the Milets, the Cimmerians, the Persians, the Romans, the Byzantines, the Seljuks and the Ottoman Empire. Sinop Castle, which could survive until today, has a length of 880 m in the North, 500 m in the east, 400 m in the south and 273 m in the west, and it defines the old borders of the city. It is observed that northern city walls of castle (Kumkapi Site) have been subjected to natural influences due to the its location and it is in danger of collapse. The purpose of scientific research on materials used in historical buildings; to obtain more information about visual, physical, mechanical and mineralogical properties of materials used in these structures. Using this information, suggestions on material selection to be used in the restoration of structures will be presented. In this study, stone and mortar samples were taken from the northern city walls of castle (Kumkapi Site) under the necessary laws and regulations. It was paid attention for the stone and mortar samples taken from the area at the sea level of the castle were intact. Samples of stone and mortar are masonry samples on the front surface, filler part and back surface of the castle. As physical analyzes on the samples; water absorption rates (bulk/weight), real density, apparent density, porosity, and pressure resistance tests as mechanical analysis were applied. In accordance with the results obtained, the suitability of the material with the material values used in the literature was emphasized. In addition, it was aimed to suggest restoration proposals that compare the mortar samples taken from the castle walls with the mortar samples of some researchers in the literature.

This study investigated the effects of precursor type, NaOH molarity, and thermal curing temperature on the performance of geopolymer mortars produced using fly ash (FA), ground granulated blast-furnace slag (GBFS), metakaolin (MK), and waste brick powder (WBP). Mortars were activated using 12 M and 16 M NaOH solutions at a constant Na₂SiO₃/NaOH ratio and thermally cured at 60 and 90 °C for 24 h. Physical, mechanical, transport, microstructural, and cost-performance properties were evaluated. The results demonstrated that the optimum activation conditions strongly depended on precursor type. MK-based mortars cured at 16 M–90 °C exhibited the best overall performance, achieving the lowest apparent porosity (6.1%) and water absorption (5.4%), and the highest oven-dry density (2194 kg/m³), compressive strength (25.8 MPa), and flexural strength (3.43 MPa). These mortars also exhibited the lowest capillary water absorption (1.88 kg/m²), the highest electrical resistivity (248.00 kΩ·cm), and the lowest charge passed (177 C), indicating enhanced pore refinement and chloride-ion penetrability. In contrast, GBFS performed better under milder activation conditions, whereas WBP showed lower performance due to its coarser, more crystalline structure. SEM/EDS analyses confirmed that the formation of dense aluminosilicate gel governed matrix quality and overall performance. Overall, MK activated at 16 M and cured at 90 °C provided the most favorable balance between technical performance and cost efficiency.