Sharif Digital Repository

Using appropriate box as an artificial boundary condition is one of the critical tasks in geotechnical physical modeling of the soil mass especially under cyclic loading such as earthquakes. In general there are two types of boxes which can simulate boundary conditions of scaled models as rigid or flexible conditions. Main purpose of this study is design and construction of a flexible box in a way that effects of boundary condition have been minimized during tests. Construction of this box is the first step of an investigation project which concern to evaluate the effect of lateral spreading as a result of liquefaction on deep foundations of bridges, piers, harbors by using shake table test... 

Liquefaction induced lateral spreading is defined as the lateral displacement of mildly sloping grounds or those ending in free faces as a result of liquefaction in subsurface soil layers. Damages imposed by lateral spreading on pile foundations supporting different types of structures such as ports, bridges and buildings are usually observed in large earthquakes. These potential damages are of high degree of importance in southern and northern coastal areas of Iran where several ports and critical facilities are located. River banks all over the country where bridge piers exist are also among the areas prone to potential damages. Evaluation of the effects of lateral spreading on existing... 

This thesis contains experimental studies on mechanical properties of adobe and mud material and investigating seismic performance of a conventional adobe house using shake table tests. Mechanical properties of adobe and mud material were studied experimentally based on ASTM and BS standard tests. These experiments were designed to evaluate compressive strength of adobe sun-dried blocks and mud mortar cubes. Besides, shear behavior and tensile bond strength of adobe assemblages were under consideration and shear tests were done on adobe panels. As next part of the research, several shaking table tests were conducted on a dome-roof adobe house as a conventional representative of arch-roof... 

The phenomenon of soil liquefaction has caused significant damage to deep foundations of engineering structures such as bridges and buildings in past earthquakes. In recent years, many researchers have studied the effects of soil liquefaction on the pile response, but there are still many unknowns that require further research and study. The present study is part of a comprehensive research that involves several Ph.D. and master students at Sharif University of Technology (SUT). In this study, the effects of soil liquefaction on two pile 2×2 groups (one with a lumped mass and another without) in a level ground with a sloping bed were investigated. A surface non-liquefied layer was also... 

In order to investigate the behavior of unreinforced masonry buildings and the effects of shotcrete retrofit, a half-scale one-story masonry building was constructed and tested on the shake-table of Earthquake Research Center at Sharif University of Technology (SUT), Iran. The project was jointly founded by SUT and Ecole Polytechnique Fédérale de Lausanne (EPFL), with the support of The Organization for Development, Renovation, and Equipping of Schools of I.R Iran (DRES). The 3.7×3.7×2 [m] specimen was modeled after a typically built classroom, with eccentric window openings on one wall and a door opening on the opposite wall. The walls were constructed using half-scale 10.5×5.0×2.9 [cm]... 

The purpose of this research is to study methods of Seismic retrofitting of buried pipelines in soil slopes subjected to landslide due to earthquakes. For this purpose, two methods were considered. The first method is to increase the burial depth of pipes. To check the performance of this method, results of three physical model tests conducted by previous research groups in this project, were used. The second method is to construct flexible retaining walls adjacent to buried pipe in soil slope. Wall was selected of Expanded polystyrene (EPS) geofoam. For this purpose a physical model was built on and excited using shaking table facility of Sharif University of Technology. Simulation laws... 

In this thesis, the behavior of cold-form steel (CFS) frames equipped with various configurations of steel sheathing and K-shaped braces is experimentally investigated. Low lateral resistance is the main deficiency of the CFS shear walls. Despite their advantages, such as being lightweight, ease of fabrication, and an environmentally friendly system, their lack of adequate lateral strength prevents engineers from widely using them, especially in areas with medium to high seismicity or in mid-rise buildings. In this regard, a total of seven full-scale specimens with different configurations of steel sheathing and k-braced, with and without cladding, were tested to investigate their seismic... 

Liquefaction-induced lateral spreading is one of the most challenging problems in geotechnical earthquake engineering. This phenomenon may impose severe damages on deep foundations in large earthquakes. In this study, six physical modeling are designed, built and tested to investigate the effects of lateral spreading on deep foundations and also assess one mitigation method. The experiments were conducted using 1g shake table of Sharif university of technology. In this respect, a large laminar shear box with outer dimensions of 420, 240 and 180 cm was designed and constructed. The laminar shear box consisted of 23 steel laminates with inner dimensions of 306×172 cm. Four experiments were... 

Liquefaction-induced lateral spreading is a known cause of severe damages to deep foundations during past earthquakes. Lateral spreading often takes place in gently sloping grounds which consisted of saturated loose cohesionless soil deposits. Several researchers during recent years have been studying the behavior of piles and soil-pile interaction under lateral spreading but there are still many unknowns in this regard. Also with observing catastrophic damages during past earthquakes caused by lateral spreading, developing proper mitigation measures for existing vulnerable piles against this phenomenon is a necessary act. In the present research, the behavior of a 3x3 flexible pile group... 

Lateral spreading is defined as finite lateral displacement of mildly sloping grounds or those ending in free faces induced by liquefaction. The phenomenon of lateral spreading caused by liquefaction in coastal areas and mildly sloping grounds has caused significant damage to deep foundations of engineering structures such as bridge and buildings in severe earthquakes. Since earthquake is unavoidable, therefore, it is necessary to provide appropriate solution to reduce the effects of liquefaction induced lateral spreading. Despite conducting various laboratory and field studies by previous researchers, there is still no comprehensive approach to evaluate the effects of lateral spreading on... 

Buried pipelines as vital arteries,which will play a major role in human life should be designed and implemented in such a way that withstand the least possible harm with regard economic issues.In this study we tried to use a physical model, the impact of pipeline buried in soil slope under dynamic load are examined.To achive this goal we use a rigid metal bax with dimensions of 301.5*101.5*155 cubic meters for modeling. Pipes used in these experiments has a diameter of 1.6 cm which are connected by a fulcrum to the wall box. In order to measure strain generated in the pipe we use a series of strain gauges that were installed using the pipe at some points. Physical models made on Sharif... 

The purpose of presented thesis, is modeling of the buried pipelines in soil slopes under dynamic loading using experiments on the physical model. Hence, numerical models based on five physical models, which are built and experimented on Sharif University of Technology’s shaking table device, have been analyzed using ABAQUS finite element software. In each model, several pipes are buried in slope, and the angle-wise placement of pipes differs with respect to slope slide. For the purposes of modeling, the experiment box has been modeled as rigid body. In order to model the soil behavior, Strain –dependent nonlinear elasticity, and mohr-coulomb criterion, has been employed. In addition,... 

In the past few decades, shaking tables are widely used to evaluate system response of structures under seismic excitations. These devices are used without any fundamental research performed on a shaking table system as an entity model. In most of these studies for simplicity, it is assumed that there exist no considerable vibration and displacement around the shaking tables, and no attention is paid to the peripheral substances such as soil settled under the foundation.
In this thesis, result of ambient vibration test on shaking table system (solid deck, concrete foundation and soil layer) has been presented. Precise sensors known as low frequency and high accuracy accelerometers have...