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Improving the characteristics of local low-strength soils at the construction site is one of the appropriate approaches to employ the soils as a backfill of geogrid-reinforced soil (GRS) walls. In this study, the fiber-cement-treated sand–silt mixture was used as the backfill of walls. The post-earthquake performance of the walls was evaluated by applying the sinusoidal waves on 1 m high reduced-scale physical models and conducting a series of 1g shaking table tests. A comparison of the wall models constructed with treated and untreated backfill indicated the advantages of geogrid-reinforced fiber-cement-treated soil walls subjected to strong ground motion. The results revealed the better behavior of the wall models backfilled with treated soil mixtures under dynamic loading. Such improved performance was more evident in (i) deformation responses, including the lateral displacement of wall facing, deformation mode, failure surfaces, and settlement of backfill surface and (ii) acceleration response in different locations, including facing, reinforced, and retained zones of walls.

Soil cohesion is one of the main parameters in designing mitigation methods for shoring to support deep excavation. Therefore, construction cost of tall buildings with deep excavation in large cities is greatly dependent of cohesion. Because of problems encountered with undisturbed sampling, in-situ testing has an important role in determining soil parameters. Cementation generally increases soil cohesion. On the other hand, new geotechnical design codes propose statistical methods as the rational method for analysis and representation of soil data in order to capture soil parameters uncertainties. This paper aims to explore the characteristic values of coarse-grained alluvium based on experimental results of in-situ direct shear and plate load at the edge of trench tests. The site location in in Tehran, capital of Iran, with coarse-grained soil consisting of gravely sand to sandy gravel with some cobbles and boulders, mostly cemented by carbonaceous materials. Statistical analysis has been done between cohesion and angle of internal friction. Also, probability distribution functions have been fitted to soil parameters. The obtained results indicate that friction angle has a truncated normal distribution but cohesion can be presented with lognormal distribution. The sample test show correlation coefficient of 0.45 between c′ and φ′ stating a positive correlation. Furthermore, characteristic values of these parameters are determined based on different methods and the results have been compared with each other. The characteristic value of cohesion and friction angle calculated in the range of 25 to 50 kPa and 30 to 35°, respectively. Global stability analyses with different calculated characteristic values are also performed. It is presented that characteristic value evaluation is an important step in geotechnical practices.

Ground improvement of the granular soils by the inclusion of geogrid makes it possible to increase the final bearing capacity of these soils. The lack of urban land, usually the construction of new...

Slope failures along highways can highly affect the stability of road structure. In this respect, the analysis of the wetting process in unsaturated media is of great importance to slopes and pavements. In this study, the Barcelona basic model (BBM) was implemented in finite difference-based program to investigate the geomechanical behavior of fine-grained unsaturated soils subjected to wetting. This numerical modeling has been verified against some data in the literature. The application of the model was investigated for the response of a compacted fill slope involving suction-induced problems. The study also considered the effect of the over-consolidation ratio (OCR) in unsaturated soils, especially stress paths, as a modification to BBM. The simulations also include using BBM and modified BBM in FLAC to evaluate the response of deep soil mixing (DSM) improvement method in subsurface areas of the pavements in unsaturated media. Finally, modified BBM codes in the finite-difference program were presented for dealing with problems associated with soil slope and the DSM method to improve the foundation of pavements. Also, over-consolidation ratio has been added to BBM to optimize its application in suction various processes. Overall, it has been found that the modified BBM leads to more occurred results.

The mechanical behavior of geo-materials depends on the assemblage structure and fundamental characteristics of constituting particles such as their shape, size and mechanical properties. Anisotropy is an intrinsic macroscopic material property that quantifies the differences in mechanical resistances to loading directions. In this study, the discrete element method (DEM) is used to investigate the anisotropic behavior of geo-materials like rocks. The model considers a fabric tensor characterizing the internal structure of particles associated with the anisotropy. The new fabric tensor proposed in this research is termed the particle stiffness fabric tensor (P-S fabric), which associates the stiffness (k in the traditional DEM) with the anisotropic state parameters. The results show that the discrete nature of the proposed approach allows an effective modelling of the anisotropic behavior of rocks. Numerical experiments are conducted on standard Brazilian tensile strength (BTS) tests with different anisotropic configurations using the PFC2D code. The tensile strength obtained shows that the results based on the proposed particle stiffness fabric tensor have a much better agreement with experimental results compared with conventional numerical modelling approaches.

Cemented Material Dams (CMDs) have drawn much attention over the last two decades. This study aims to assess the performance levels and capacity of CMDs using Incremental Dynamic Analysis (IDA) with emphasis on the tension failure mode. To this end, Tobetsu dam in Japan was subjected to a set of 17 ground motion records scaled to increasing intensity levels until failure. Then, by considering IDA curves, three limit states were defined for the dam and then, the extent of the damage to its body was quantified through several damage indices. Based on the results, the proposed damage index outperformed available indices in the literature and accordingly, four damage states were defined in line with the proposed index. Finally, fragility curves were derived for Tobetsu dam based on IDA results. The findings revealed that the concentration of stresses in the dam body, especially heel and neck, was insignificant. Moreover, the mean values of the IDA curves in the downstream and upstream directions were in good agreement. Also, the results indicated that the compressive stresses developed in the dam body were much lower than the compressive strength of the material.

Construction of mechanically stabilized earth (MSE) walls in multi-tiered configurations is a promising solution for increasing the height of such walls. The good performance of this type of walls after recent major earthquakes was reported in a number of technical studies. In the present study, an experimental approach was adopted to compare the seismic performance of single-tiered and multi-tiered MSE walls using physical modeling and through conducting a series of uniaxial shaking table tests. To do so, several geogrid-reinforced soil walls with wrap-around facing (i.e., three-, two-, and single-tiered) with a total height of 10 m were designed in the form of prototypes of 1-m-height wall models. The step-wise intensified sinusoidal waves were applied to the models in 14 typical forms. Comparing the shaking table test results confirmed the post-earthquake advantages of multi-tiered MSE walls. The results revealed that tiered walls exhibited better behaviors under earthquake loading in terms of the seismic stability of the wall, displacement of the wall crest, horizontal displacement of the wall facing, deformation mode and failure mechanism of the wall, settlement of backfill surface, and seismic acceleration responses.

An innovative method for modeling a complicated geotechnical problem combining the coarse and fine zones is to use the hybrid methods. The granular zone of a geotechnical system can be modeled by the discrete element method (DEM) and the fine zone by continuum-based methods. The advantage of this approach is the use of the capabilities of both methods. In the present research, by combining DEM and finite difference method (FDM), a 2D numerical laboratory framework is constructed. Simulation of a vertically loaded stone column installed in clay was chosen to examine the capabilities of the present approach. The contrast between the stone column aggregates, which usually consist of crushed stone with distinct behavior, and the host medium, which is clay with continuum behavior, makes the stone column suitable for this kind of coupled simulation. The coupled numerical model is validated by comparing the load–settlement response of the numerical model and the reported experimental results. Afterward, the failure mechanism of the stone column is evaluated. The column bulging was captured properly, and it was found that in addition to the bulging, the contraction occurs at the upper portion of the column. It was also found that at the early stages of loading, the compaction occurs in the column. However, at later stages of loading, the bulging will happen. Furthermore, the results showed that bulging decreases the internal stresses of the column. All of these achievements were obtained by micro and macro investigations. The obtained results indicate that the coupled DEM–FDM method is a robust approach to simulate the behavior of some geotechnical problems.

The present research focuses on the simulation of encased stone columns in a 2D state by utilising the coupled finite difference method (FDM) and discrete element method (DEM). The stone column material was modelled by DEM using irregularly shaped particles, and the geotextile used as the encasement of the stone column was simulated using parallel-bonded particles. The surrounding clayey soil was modelled by FDM. Two models were combined by employing a direct coupling method. After validating the coupled DEM-FDM model through comparisons with experimental results, the encased stone column was investigated at the micro and macro scale. The results indicated that the coupled model can imitate the behaviour of the encased stone column to a reasonable degree. Furthermore, the encased stone column exhibited different deformation behaviour than the ordinary stone column. The use of the encasement decreased the stress deviation at the top and bottom of the column. Also, the soil surrounding the encased stone column displayed different displacement behaviour than the soil surrounding the ordinary stone column. In addition, the effect of encasement length on stone column responses was examined.

Due to the lack of soil with sufficient load-bearing capacity and the ever-increasing number of large-scale building projects, methods for soil improvement have become vital. Among the conventional methods of soil improvement, the use of reinforced and ordinary stone columns is one of the most prevalent; this is due to its environmental compatibility and proven effectiveness. In this paper, the mechanical behavior of ordinary and reinforced stone columns was studied using ABAQUS, a finite element software. A3D nonlinear finite element model of the column-improved soft soil was built. The results of this work show that while the columns alone decrease the soil settlements, the combination with the geosynthetics additionally augments the effects. Parametric studies were completed to illustrate the effects column grouping on the design process. Thus, the effects of parametric exploration, including inter-column spacing parameters as well as the length and diameter of the stone columns, on the reduction of settlements and bulging were studied for different conditions.

In this paper, 3D discrete element method (DEM) simulations are proposed to explore the mechanism of arching within geosynthetic-reinforced and unreinforced piled embankments. Comparisons are made between the numerical and the measured data of IFSTTAR centrifuge tests with regards to efficiency response, volumetric deformation and displacement characteristics to verify the DEM. Resulted show that, considering the kinematic of the arching process, discrete nature of the utilized numerical model for soil allows a good description of the evolution of the load recovery stage and contact forces within the granular material. Also, simulation results confirm that the load recovery phase can take place in geosynthetic-reinforced cases when geosynthetic layer has not enough stiffness to support the arch load which causes the geosynthetic destroy prior to reaching maximum efficiency. Further, the numerical investigation is extended to examine the effects of the vertical spacing of the second layer of the reinforcement on efficient and differential settlement. Findings indicated that, when second layer of the reinforcement is used, there is an optimum vertical spacing for which the lowest value of the differential settlement is reached. In addition, analyses indicate that increasing reinforcement stiffness has a lower influence on achieving the maximum efficiency in the lower settlement than increasing the number of reinforcement layers, if the second layer of reinforcement is placed within an effective height range.

In this paper, an approach for soil liquefaction evaluation using probabilistic method based on the world-wide SPT databases has been presented. In this respect, the parameters’ uncertainties for liquefaction probability have been taken into account. A calibrated mapping function is developed using Bayes’ theorem in order to capture the failure probabilities in the absence of the knowledge of parameter uncertainty. The probability models provide a simple, but also efficient decision-making tool in engineering design to quantitatively assess the liquefaction triggering thresholds. Within an extended framework of the first-order reliability method considering uncertainties, the reliability indices are determined through a well-performed meta-heuristic optimization algorithm called hybrid particle swarm optimization and genetic algorithm to find the most accurate liquefaction probabilities. Finally, the effects of the level of parameter uncertainty on liquefaction probability, as well as the quantification of the limit state model uncertainty in order to incorporate the correct model uncertainty, are investigated in the context of probabilistic reliability analysis. The results gained from the presented probabilistic model and the available models in the literature show the fact that the developed approach can be a robust tool for engineering design and analysis of liquefaction as a natural disaster.

This paper compares the behavioural models of municipal solid waste (MSW) using the corresponding experimental data. To do so, the proposed models are first reviewed and, then, the algorithms and codes of different models are written. After obtaining each model’s algorithm, the same experimental data are considered as input, and the strain–stress curve is plotted for each model. In the first method, the total strain in the waste is obtained based on the summation of the elastic, plastic, biological, and creep strains. Afterward, the equivalent stress is obtained. In this method, using biological changes over time, the age of the waste is calculated as an effective parameter in MSW behaviour. Moreover, the effect of creep on the waste is considered independently. In the second algorithm, MSW is considered as fibre and paste material, and the strain–stress curve is obtained. In this method, the waste is considered as a soil model, and the effect of different parameters are calculated. Due to the complexity of the MSW behaviour and considering various parameters, such as the age of the waste, E changes over time, creep, and biological changes, the Krase model has less error than the other models. Using the soil behaviour model for the waste has a significant error, indicating the difference between the results for the behaviours of the two substances.

The Barcelona Basic Model (BBM) has been implemented in a finite difference-based computer program to simulate the behavior of unsaturated soils subjected to wetting. The BBM implementation was verified using analytical solutions, and the proposed model has been used to simulate the response of a compacted embankment under complete saturation and suction induced conditions. Numerical analyses indicate that considerable amount of total and differential settlements could develop at the top surface of the embankment. BBM is executed into FLAC2D extending a defined module for modified Cam Clay (MCC) and has been set up an analytical solution for suction-dependent stress and strain. Evaluating the effect of anisotropy and nonlinear apparent tensile strength in unsaturated soils, a modification to BBM formulation has been proposed and optimized by developing numerical analyses to reduce the size of elastic region of loading collapse (LC) curve. Then, an experimental study in the literature is investigated by utilizing comparative curves from BBM and modified BBM indicating well agreement with natural circumstances. As a result of the work presented in this research, finite difference codes with BBM and modified BBM has the capability of simulating the real behavior and is operational being applied to problems associated with earthen structures in unsaturated or partially saturated of expansive soils as a three-phases medium.

This study mainly approaches evaluating the effect of air deck length (ADL) and its different positions (ADP) on blast-induced ground vibration and development of damage zone. The peak particle velocity (PPV) was used as a tool to achieve this goal. Three different positions (at top, middle, and bottom of the blast hole) in a rock slope under the blast load were simulated using 3D discrete element numerical code. The modeling was conducted in two modes: (1) columnar charge of blast hole and (2) considering an air gap in the explosive column with lengths of 1.5, 2, and 3 m. The PPV values at the ground surface were estimated continuously along a line from the blast hole collar to the end of the model. Finally, the results obtained from numerical simulations indicated that the use of air deck technique could reduce the costs of consumed explosive by 30 to 45%. It was also found that top column air deck increased the surface vibrations of the ground up to 36%. However, the middle and bottom column air decks have no significant effect on the reduction of blast-induced ground vibrations.

In this study, a developed simple new expression is suggested to analyze an impact of geometric dimensions of geogrid and its influences on increasing soil bearing capacity under the strip footing. The longitudinal and transverse elements in the reinforcement geogrid perform an essential function in resisting tensile stresses in reinforced soil. Therefore, the geogrid passive tensile strength is evaluated by the general shear failure pattern of Terzaghi’s theory. Since the failure in reinforced soil takes place as a result of increased stress affecting the tensile strength of the geogrid transverse and longitudinal ribs, the passive bearing mobilized strength is calculated according to the general shear failure of the theory of Terzaghi. The impact of bearing member rigidity, characteristic of geogrid surface, and the shearing mechanism inside the soil mass reinforced through the geometric proportions of the reinforcing element was investigated. A series of 22 numbers of experimental tests were carried out on both reinforced and non-reinforced soils. One type of fine sand and geogrid reinforcement were utilized in small-scale physical modeling. The influence of embedment depth of the first geogrid layer, vertical distance between two geogrid layers, and geogrid’s length was investigated by conducting different footing widths of plate load tests. The arrangement of the geogrid layers was also investigated to demonstrate how they affected parameters study and the results. Parameters affecting soil tolerance equation include interior friction angle of soil, coherence, geogrid tensile modulus, geogrid opening dimensions, thickness and length of longitudinal and transverse elements, soil unit weight, and footing width. The results were compared with some previous research findings. Then, new simple metric criteria were used for evaluation of quantitative expression of errors of new bearing capacity equation by regression analyses. The calculations indicate that the median error rate is less than 8%. As a result, the laboratory study confirms high-grade compatibility with a new bearing capacity expression.

This article presents the interface shearing behaviour of a granular soil layer in contact with a bounding structure under motion. For this purpose, an elasto-plastic Cosserat continuum model (EPCC...

Alluvial fan is one of the environments having good potential for aggregate exploitation. Morphometric properties of alluvial fans’ catchment such as area and length of main channel have important role in the aggregate attributes. The aim of this research is to study the relation between morphometric characteristics of catchments and aggregate size and weight loss resulted from freeze–thaw and sodium sulfate soundness. To achieve the aim of this study, 12 alluvial fans on northwest of Direh catchment in Gilan-e Gharb county were selected. All selected fans having catchments with similar lithology were selected in this study in order to eliminate the effect of lithological differences in freezing–thawing test. Results show that as area and length of main channel in catchments increase, the rates of fracture, weight loss due to freezing–thawing, and sodium sulfate soundness decrease. The rate of weight loss is originated from morphometric characteristics of alluvial fans’ catchments. As area and length of main channel in catchments increase, the weight loss difference (from freezing–thawing and sodium sulfate soundness) between fine and coarse aggregates decreases. Indeed, the effect of particle size in the intensity of weight loss reduces with increase in area and length of main channel of catchments.

One of the main concerns in using commercial software for finite element analyses of dam-foundation-reservoir systems is that the simplifying assumptions of the massless foundation are unreliable. In this study, an appropriate direct finite element method is introduced for simulating the mass, radiation damping and wave propagation effect in foundations of dam-foundation-reservoir systems using commercial software ABAQUS. The free-field boundary condition is used for modeling the semi-infinite foundation and radiation damping, which is not a built-in boundary condition in most of the available commercial software for finite element analysis of structures such as ANSYS or ABAQUS and thus needs to be implemented differently. The different mechanism for modeling of the foundation, earthquake input and far-field boundary condition is described. Implementation of the free-field boundary condition in finite element software is verified by comparing it with analytical results. To investigation the feasibility of the proposed method in dam-foundation-reservoir system analysis, a series of analyses is accomplished in a variety of cases and the obtained results are compared with the substructure method by using the EAGD-84 program. Finally, the massed and massless foundation results are compared and it is concluded that the massless foundation approach leads to the overestimation of the displacements and stresses within the dam body.

The behavior of unbound granular material under repeated loads primarily depends on the nature and arrangement of constituent particles, particle size and shape. However, very few analytical models are available for predicting the behavior of unbound granular material under repeated loads. This paper presents a generalized failure criterion with a non-associated flow rule which uses from the concept of compact shakedown state for predicting the stress–strain behavior of unbound granular material. At the compact shakedown state, the response of the unbound granular sample to a stress change is reversible and behaves as an elastic material. In an extension to original CANAsand constitutive model, two concepts namely critical state and compact shakedown state play paramount roles as all of the moduli and coefficients are related to these states. In contrast to the critical state, the unbound granular material samples do not experience any plastic deformation at the compact shakedown state and behaves as a purely elastic material and the response to a stress change is reversible. For stress reversal two additional concepts as reflected plastic potential and bounding surface are employed which distinguishes between virgin loading and secondary loading. The extended model is examined by simulating different typical drained tests in conventional tri-axial tests. The applicability of the present model is evaluated through comparisons between the predicted and the measured results.

A novel generation of gravity dams, known as cemented material dam (CMD), allows construction of dam body on almost every rock foundation even on very low modulus and weak rocks. Because of its rock weakness and antiearthquake features, more considerations are required for its design. Therefore, a probabilistic model code based on coupled Monte-Carlo and Fuzzy simulation is presented to put together regulations, rules and explanations necessary for serviceability assessment of CMD. The proposed code is contained of the sensitivities of tensile stress, compressive stress and sliding. Then, finite element method (FEM) is utilized to verify the overall strength security and stability for a case study. The results indicated that for the optimal cross-section, the upstream as same as downstream dam slopes are 1:0.45 to 1:0.80. In addition, the vertical and horizontal displacement contours increase from bottom to top of the dam. The maximum values of horizontal and vertical displacements are within the permissible limit of 1–2% dam height. The results also demonstrated that elastoplastic constitutive model is more suitable to safely predict the behavior of CMD than other models in statistical and dynamical conditions.

Transporting finer fractions inside the soil skeleton or the erosion of base soils within the filter are the two main challenges for earthen hydraulic structures, their foundations, and filter design. Soil particle morphology could influence pore size distribution and transport of fine grains; however, there is not sufficient knowledge on the effect of grain shape on internal erosion. Some experiments designed and conducted in the present study to evaluate the suffusion potential of aggregates with various shapes and different gradations. Particles with six types of grain morphologies and five gradations were collected, and 26 tests were performed. Furthermore, using 3D image processing and visual comparison, particle shape assessed in terms of three features, including sphericity, roundness, and roughness. Results indicated that particle shape influences flow rate, washed-out fine grains in permeameter wall, vertical strain, and mass loss. An increase in the sphericity and roundness causes an increase in the loss of fine grains, pipe in cell sidewall, and vertical strain. Concerning the particle regularity as an indicator of grain morphology, it was demonstrated that the grains with lower regularity are more resistant to suffusion, and thus the resistance to suffusion would decrease with particle regularity. Spherical glass bead and rounded/ medium sphericity specimens were more prone to suffusion at an equivalent or even lower hydraulic gradient than the soil samples with angular/low sphericity grains.

Ground vibration is one of the most critical undesirable factors of blasting. In this study, the effects of the blast damage factor and blast design parameters in a rock slope through applying the dynamic blast loading on ground vibration are investigated. Modelings were conducted considering three major geological discontinuities with a spacing of 15 m and a 45 degrees dip relative to slope face. A 3D discrete element code (3DEC Version 5.2) was used for this purpose. The pressure-decay function was used to simulate the dynamic pressure of detonation. Peak particle velocity (PPV) was selected as the main indicator to evaluate the effects of each one of these parameters by utilizing FISH programming language. Therefore, the PPV values were recorded continuously from the blast hole collar to the end of the model. The effects of rock mass quality (which is affected by the reduction in blast damage factor) and the parameters of hole diameter, burden, and spacing, stemming length, and blast delay time on the PPVs are investigated. The obtained results from numerical simulation indicated that the blast damage factor has a significant effect on ground vibrations. Moreover, it was also found that delay time is less effective than other blast design parameters on ground vibrations.

Both experimental and numerical investigations conducted on strip footing laying down over the geogrid reinforced fine sand bed. Firstly, an evaluation of the significance of geogrid reinforcement to enhance the soil’s strength is required to carry out a series of a small-scale model of reinforced and unreinforced soil beneath static loading. Next, the series of the large-scale numerical analyses were implemented to define the soil bed reaction modulus and bearing capacity ratio of reinforced sand soil in plane strain conditions. The Mohr–Coulomb soil constitutive model was used to represent the fine sandy soil and the linear elastic tension model was utilized for modeled geogrid reinforcement elements. One of the most beneficial outcomes in the unreinforced soil case, the ultimate bearing capacity progress occurs by developing the width of the strip footing. Then in reinforcing case, an uppermost geogrid layer’s depth under the footing and the fittest spacing between the reinforcing layers are not affected by the wide ranges of the footing widths. Their optimum values are similar to the works of literature (u/B = 0.3 and h/B = 0.4), but they are affected by soil friction angles. Finally, the achievement of this study indicates that the coefficient of soil reaction is associated with a nonlinear behavior with the relative ratio of tensile stiffness of the geogrid to the elasticity modulus of soil and enhanced by increased the number of geogrid layers. The influence of geogrid length on subgrade modulus is negligible and only the effective depth is affected it. The value of reaction modulus decreases when both the footing width and settlement increase. A simple new method is proposed to determine an approximate value of subgrade reaction modulus in reinforced soils.

The abrasion and impact resistance of aggregates are important factors that should be taken into consideration during the production of concrete or asphalt that are subjected to abrasion and impact. The aim of this study was to examine the relationship between abrasion and impact resistance of aggregates related to the rivers, alluvial fans and taluses. In order to achieve this purpose, samples were collected from 3 rivers, 12 alluvial fans and 2 taluses located in Direh in Kermanshah province, Iran. The samples were studied in terms of changes in void ratio, cracks and weight loss induced by abrasion and impact. The lowest amount of weight loss due to abrasion and impact was observed in aggregates from rivers, with about 30% weight loss due to abrasion and 15% due to impact. The highest amount of weight loss was found among aggregates collected from taluses (45% for abrasion and 35% for impact). This results can be attributed to the degree of cracks and porosity in aggregates. It was also observed that the abrasion and impact resistance of aggregates in alluvial fans was dependent on the morphometric properties of alluvial fans catchment. Thus, a lower amount of weight loss caused by abrasion and impact was in aggregates taken from alluvial fans with larger catchments and longer main channel catchments.

Concrete dams are one of the most important infrastructures in every country and the seismic safety assessment of them is a major task in dam engineering field. Dam–foundation–reservoir system analysis is a complex interaction problem because this system consists of three domains with different behaviors. For accurate analysis of this system, some important factors should be considered such as foundation mass and earthquake input mechanism. In this paper, the effect of foundation mass and earthquake input mechanism on seismic response of concrete gravity dam is investigated. For this purpose, two different methods are introduced for modeling of massed semi-infinite foundation in finite element method, namely free-field boundary condition and domain reduction method (DRM). To verify the feasibility of proposed methods for seismic analysis of dam–foundation–reservoir system, the displacement and stress outputs using proposed methods are compared with EAGD-84 results. The obtained results indicate that both methods are accurate enough for finite element modeling of massed foundation. Finally, Koyna concrete gravity dam is analyzed for rigid, massless and massed foundation cases using DRM and it is concluded that the foundation has significant effect on dam response and the common massless foundation approach overestimates the dam response.

Dams constitute a potential hazard to downstream life and property. Therefore, it is necessary to detect any signs of abnormal behaviour in structural safety. Monitoring of an embankment dam plays ...

Temporal and spatial monitoring play a significant role in evaluating and examining the riverbank morphology and its spatiotemporal changes. Unlike the terrestrial laser scanners, other previously used methods such as satellite images, total station surveying, and erosion pins have limited application to quantify the small-scale bank variations due to the lack of rapid survey and resolution in data acquisition. High cost, lack of availability, specialized equipment and hard movement of laser scanners make it necessary to develop new accurate, economical and easily available methods. The present study aims to test the Kinect photogrametric technology for measuring and assessing riverbank variations in laboratory environment. For this purpose, three models of layered soil blocks for three different levels of groundwater (i.e. 24, 34 and 44 cm) were designed to investigate the seepage erosion behavior experimentally. The results indicate the high accuracy of Kinect in measuring the bank erosion cavity dimensions (i.e., 0.5% error) with high spatial resolution data (i.e. 300,000 points per frame). The high speed of Kinect in riverbank scanning enables the analysis of time variations of mechanisms such as seepage erosion which occurs rather rapidly. The results confirmed that there is a power relationship between the seepage gradient and the time of the bank failure with a determination coefficient of 0.97. Moreover, an increase in the level of groundwater on the riverbank increases the rate of undercutting retreat that caused more rapid failure of the riverbank.