207 publications from this institution
Historical masonry domes are an important part of the architectural and engineering heritage in the World. They have been extensively used to cover the spaces of temples, mausoleums, palaces, forts, baths, churches, mosques, etc. Damages and collapses of masonry domes occurred as a result of earthquakes or lack of maintenance. Therefore, many efforts have been devoted to clarifying the theoretical and experimental responses of masonry domes by researchers. In addition to traditional techniques, significant developments have been achieved on the strengthening of masonry domes using innovative techniques. The study firstly presents a complete review on the state of knowledge about theoretical and experimental responses and strengthening of masonry domes under static and dynamic loads. Then crack patterns and failure mechanisms of masonry domes are explained, and traditional and innovative strengthening techniques that can be rehabilitated the masonry dome without any harmful intervention or disagreement with conservation principles are introduced and evaluated in detail.
So far, little attention has been paid to the investigation on the seismic failure mechanisms of flexible concrete pile groups embedded in the layered soft soil profiles considering the material non-linearities of soil and concrete piles. The purpose of this study is to investigate seismic failure mechanism models of flexible concrete piles with varied groups in silt layered loose sand profiles under horizontal strong ground motions. Three-dimensional finite element models of the pile–soil interaction systems, which include nonlinearities of soil and concrete piles as well as coupling interactions between the piles and soil, were created for Models I, II, and III of the soil domains, encompassing 1x1, 2x2, and 3x3 flexible pile groups with diameters of 0.80 m and 1.0 m. Model I consists of a homogenous sand layer and a bedrock, Models II and III are composed of a five-layered domain with homogeneous sand and silt soil layers of different thicknesses. The linear elastic perfectly plastic constitutive model with a Mohr–Coulomb failure criterion is considered to represent the behavior of the soil layers, and the Concrete Damage Plasticity (CDP) model is used for the nonlinear behavior of the concrete piles. The interactions between the soil and the pile surfaces are modeled by defining tangential and normal contact behaviors. The models were analyzed for the scaled acceleration records of the 1999 Düzce and Kocaeli earthquakes, considering peak ground accelerations of 0.25 g, 0.50 g, and 0.75 g. The numerical results indicated that failure mechanisms of flexible concrete groups occur near the silt layers, and the silt layers have led to a significant increase in the spread area of the damaged zone and the number of damaged elements.