Understanding of the geological characteristics of artificial stone is of particular importance. Appearance, size and dimensions, specification of particle surface and minerals forming aggregates are among the characteristics of rock materials that affect the homogeneous and cladding environment. Volume variations, water absorption, resistance to atmospheric agents and wear resistance are the most fundamental features of Engineering stone in artificial stone. In this research, to investigate and compare the resistance properties (Uniaxial Compression, Brazilian, Point Load, Ultra Sonic) and the physical properties of artificial stones made with additives (polyester resin, vinyl ester resin, glass fiber and aggregate type) with three granite samples, we will cover the Alamut granite, Takab granite and Nehbandan granite. The results of the study show that the glass of fiber glass samples compared to non-woven glass made of resin and aggregates, has more 15% of tensile strength, 14% of uni-axial compressive strength and 12% of the point load index. As well as, resistance of samples made with a leaden resin is 1. 64 times more than polyester resin specimens. Based on this study, the mixing plan and percentage ratio combination is the most important principle in the strength and strength of artificial stone

The coarse-grained alluvium of Tehran area has undergone cementation processes through the time that notably affects its strength. The rate of cementation is influenced by many factors including original texture, type and shape of grains, geological history, ground water conditions, tectonically pressures, depth and weathering processes. The main geotechnical features of the alluvium such as strength, stiffness, bearing capacity, and stability of slopes and underground excavation is directly related to the degree of cementation of this deposit.This paper reviews the process of cementation of Tehran's alluvial deposit and considers the effect of cementation on the mechanical behaviour of the deposit. Cementing material of Tehran alluvium predominantly was deposited by groundwater. The composition of the cement material is carbonated and is mainly consisted of calcite. The original texture and gradation of the soil has a considerable effect on cementation process and strength. When the content of fine materials is less than about 15%. The cement material bonds directly the coarse grain particles. On the other hand, When the content of fine grains exceeds 15%, the contacts between coarse particles is dominantly by that material, so the strength of deposit is mainly affected by fine materials. The results of in-situ and laboratory tests show that the cementation increases the strength and stiffness of soil, and changes the ductile behaviour of soil to brittle during shear. Moreover, the cementation increases the failure envelope curvature.  

Uromieh Lake, which forms a closed, intermontane basin, located in northwest of Iran and is the biggest lake in the country. The lake has 5000 square kilometers area, with 140 km length and 15 to 50 km widths. Based on interpretations upon tectonic evolution of the region, Uormieh Lake is considered as a remnant portion of Tethys Ocean. The present situation of the lake shows that, it is surrounded by a few faults and forms a tectonic depression. Saturated clay and silt deposits overlying on bed rocks show evidence of marine fossils and demonstrate that earlier deposited environment of the lake was not so much salty. The source of soft sediments in the lake which were transported through north and south runoffs and floods are mainly comes from playa deposits of Maragheh Formation, Certaceous and Neogene shale and sandstone, limestone of Qum Formation, and granite intrusive. Besides these silt and clay sediments, detrital sediments in form of small sandy grains and insitu chemical deposits in lesser amounts are also seen in the sediments. These detrital deposits which are colored and composed of quartz, mica, and calcite are more frequent. Clay minerals are illite, kaolinite, and chlorite. Aragonite composes most parts of chemical deposits. The amount of organic material in sediment of the lake is almost 5% but in salty lagoons of the lake this amount increase to 15%.The mean content of salt is 250 g/lit. Due to this salt content in water of the lake, except at the conjunction of rivers to the lake it takes time for suspended sediments to deposit. Based on direct observation and through core loging form boreholes which were drilled along Shahid Kalantary freeway, the soft sediments of the lake have fine bedding. In samples collected from core logging along the lake coast in Tabriz and Uormieh region, fine sandy layers with up to 2 millimeters in thickness can be seen. The existences of these layers can considerably effect Engineering characteristics of the deposits. Grains smaller than 75 micron, can be seen down to 150 - meter depth and constitute 95% of the deposits, obviously show their fine - grained nature. Sediments in the middle parts of the lake mainly consist of fine clay (CL) to silt (ML). Their activities decrease from surface to depth. By increase in activity of sediments, the amounts of internal friction, permeability coefficient (k), and consolidation index (Cv) decrease, but compaction index (Cc) increase. In general, sensitivity of top layer sediments is more than bottom one. Detail analysis on results of vane shear experiments, SPT, and uniaxial compressive strength demonstrate that shear strength of the sediments considerably increase with depth and that their sensitivity decrease in 40-45 meters depth.      

Geologically, northern slope of Alborz Mountain is divided into Khazar plain and northern border regions based on structural and stratigraphic characteristics. In order to study the pushing movement of natural slopes, side slopes in cross sections and geological and geotechnical reasons of landslides in northern slopes of Alborz Mountains, three road axes of Ghaemshahr-Firozkoh, Sari- Kiasar and Rigcheshmeh-Dodangeh have been selected. These regions are formed mostly of eluvial deposit like silty clay or clayed silt along with fine sand, which has a weak firmness. Flowage of water in the superficial layers, causes surface landslides along the slopes, so that thickness of slipped materials is about 6 to 7 m. By analyzing the results of the soil mechanics tests, the causes of failure of landslide are explained. In general, layering of the soil stratum with respect to land slope and dip of soil layers, which are the effective causes of the trenches and embankment stability, are investigated. Limestone layers which are usually perpendicular to land slope, is the reason of increasing safety factor against landslide. In some regions, existence of water in superficial soil layers causes gradual failure or mud flowing. In this research, disturbance of draining water, caused by soil practices of road construction, leads to unstability and side slope sliding is also considered. Finally, shear stress to vertical stress ratio in drained and non-drained conditions are defined as [t/σ n]d ≥0.4 and [t/σ n]u ≥0.25 which can be used as quantitative criteria to forecast the occurrence of landslide.

This paper discusses the results of the Engineering geological investigation and geotechnical studies carried out at the proposed Khersan 3 dam site. The dam will be built on Khersan River, is located about 50 km of west of Lordegan city in west of Iran. The dam is mainly founded on sedimentary rocks of the Tercier age and on Quaternary deposits. Geotechnical information obtained from both at the field and the laboratory studies. Field studies include Engineering geological mapping, surface discontinuity mapping, drilled borehole and sampling for laboratory testing. Samples obtained from drilling were tested in the laboratory, included of uniaxial, triaxial and tensile strength tests and deformation parameters, unit weight and porosity. Rock mass classifications of the dam site rock units have been performed according to RMR (Bieniawski 1989), Q(Barton et al., 1980) and GSI systems (Hoek and Brown 1997). A detailed geological and geotechnical study was carried out in the project area to determine the Engineering geological characteristics of the rock masses. In the study, rock mass properties was classified using Geological Strength System (GSI), and the Hoek-Brown equation was used to obtain rock mass strength parameters and modulus of elasticity. Finally, regarding to instability analysis in tunnel axis and probably instability wedges, suitable software based on finite element method has been used.

City of Tehran is founded on Quaternary alluvium. During the last years, several researchers have studied characteristics of this alluvium. Amongst them, Rieben classification has been the most widely used classification rather than others. Rieben (1955) divided Tehran alluvium to four categories, A, B, C and D which are ranged from old to young, respectively, in terms of geologic age. In Rieben study, age and general characteristics of alluviums are considered rather than geotechnical and Engineering applications. Study of alluvium based on age can give useful information about history of basin sedimentation and relevant change's trends and even it may help geotechnical engineers for preparing study plan and making sound conclusions over undertaken studies. For doing so, it is required to evaluate alluvium classifications with respect to sedimentation types. In order to evaluate Rieben classification capabilities for geotechnical studies of Tehran alluvium, following subjects are studied in this research: (A) Description of Rieben and other classifications that are presented based on age and specification of geology. (B) Discussing advantages and disadvantages of existing classifications in geotechnical studies. (C) Analysis of Tehran geological maps with consideration of alluvium formation and making comparison of these maps with some boreholes, test pits and site visit results. (D) Discussing geological factors affecting on geotechnical specifications of Tehran alluvium.

Pumped storage reservoirs are one of the newest systems in saving electricity. According to importance of convey water for placed the turbine and knowing that, almost of instability of underground area is for ignorance in some Engineering geology parameters, we have decided to investigate this parameters. In this research we have been studied the Engineering geology parameters along tunnel, changing in some of these parameters are shown in Rockwork 2008. After all with the new classification called IRMR the Engineering geology parameters of rock mass have been studied, compare the result with classic classification, RMR and GSI shown that the outlet and entrance of tunnel are under bad situation. At the next, studied of joint for recognized the wedge base on finite element method have been investigate. Eventually with emphasis on rock bursting, squeezing and geomechanic studied the admissible advancement step for two section of tunnel base on FLAC 3D have been carried out. Using such studied make safety in services and reduce the spent-time.

The region under study is located about 53 kilometers in the south of the Rasht, North West of the Ammarlu Mountains, and north of Iran. Due to the field studies and the data obtained from the study of geological maps of the area it was revealed that the Doulat Abad landslide is on old one. Under study one of the effective environmental factors for ancient landslide in the region under study is the Sefidrood River. Under study one of the effective environmental factors for Doulat Abad young landslide, have had the undeniable role with respect to the inherent conditions such as kind and tissue of material, uniformity direction water, slope, fault, hills shape, environmental factor. Three kinds of area were evaluated regarding the geology and Engineering geology studies on the basis of suitable environmental and inherent factors. They include:1- area that don’t heavy any landslide and instability or there is little landslide in them2- area that have partial and are liable to landslide, and3- area that have the danger of instability and serious landslide. The results of studies include 2 Engineering geology maps to the scale of 1:2000 and do rock mechanic examination that is presented with the solution for the stability of Doulat Abad landslide.