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1

Augmented and Virtual Realities: the Future of Building Design and Visualization

Solanki DivyarajSinh M., Laddha Hrushikesh, Kangda Muhammed Zain, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2023

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Vol. 33, no. 1

17--38

EN

The present study precisely conveys the methodology of developing a three-dimensional (3D) architectural model of a villa with its walk-through and displaying the model in virtual reality, which as a result, be used by the clients to spectate, customize and buy the real estate property. Additionally, the case study highlights the advancement in architecture, as certain specifications of each element of a 3D model can be viewed in a virtual environment. Virtual reality is a transpiring platform, and in addition to that, the real-estate sector shows its incorporation in designing, marketing, and selling projects. The teaching and learning process can be eased out by intervening it with technology that generates an enhanced visualization environment. These technologies, when used constructively, save time and energy and also hoard economic standards ensuing lucrative benefits.

2

Performance of Solid Waste Landfills Under Earthquake-Induced Vibrations

Seyedi Marghaki Behnaz, Soltani Fazlollah, Noroozinejad Farsangi Ehsan, Sivandi-Pour Abbas

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 2

1--22

EN

The stability inside the waste, internal stability, and co-stability between the elements of the insulation system and the landfill bed should be considered in the landfill design. The stresses and the resulting deformations in both mineral and geosynthetic materials of the insulation system must be controlled in the design, so that an unpredictable flow path is not created. Besides, long-term durability in the insulation system should be considered. An evaluation of the durability of the system requires knowledge of the interaction between the components and the waste as a settling object. The numerical modeling methods can be used to evaluate the local instability. In this study, a landfill constructed in the UK has been modeled in ABAQUS finite element platform and was verified with the results of obtained data from precision instruments at the landfill site. Then, by applying the earthquake excitations, the seismic behavior of the solid waste landfill under Far-Field and Near-Field earthquakes and their effect on the durability of the landfill wall system were investigated. The outputs include maximum displacement, maximum stress, the most critical state, and investigation of yield stress and rupture of the geomembrane layer. The results indicated that in the landfill wall, the maximum displacement occurs in the waste section. It occurs especially between the boundary of natural soil and waste. It was also observed that the geomembrane layer under the earthquake loadings had experienced some ruptures.

3

Investigation of Resilience of Eccentrically Braced Frames Equipped with Shape Memory Alloys

Pirmoghan Hamid, Khoshravi Hossein, Sadeghi Abbasali, Pouraminian Majid, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 1

176--190

EN

Nowadays, the use of smart materials in structures is a major concern to structural engineers. The act of benefiting from numerous advantages of these materials is the main objective of researches and studies focused on seismic and structural engineering. In the present study, in addition to the development of finite element models of several steel frames using ABAQUS software, the effect of shape memory alloys (SMAs) on superelastic behavior and the various types of eccentric braces will be checked. Moreover, it was observed that the use of SMAs within various types of bracing systems of steel frames leads to a decrease in the reduction factor of the frames. Also, the eccentric bracing in which SMAs are utilized in the middle of bracing led to the highest effect on reduction of lateral drift of the frames and decrease of reduction factor. The obtained results indicated that the application of smart materials led to increasing of strain energy and base shear of the first plastic hinge, which is followed by a decrease in the reduction factor of the frame.

4

Effect of Link Beam Length of the Eccentric Bracing System on Seismic Rehabilitation of Weak Reinforced Concrete Frames

Niknam Touraj, Saberi Hamid, Saberi Vahid, Sadeghi Abbasali, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2022

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Vol. 32, no. 1

152--175

EN

In this study, a reinforced concrete (RC) reference specimen with compressive strength of 250 kg/cm2 and the weak RC specimen for seismic rehabilitation with compressive strength of 150 kg/cm2 were examined in two types of structures with 6 and 12-stories. The link beam lengths of 50, 80, and 100 cm have been used in 6 and 12-stories prototypes under the effect of 7 earthquake records. The nonlinear dynamic analyses are performed. Then, The behavior of the link beam depends on its length. For short link beam lengths, shear behavior is serious, then for medium lengths, shear-flexural behavior is important, and finally, long lengths will have flexural behavior for the beam. In eccentrically braced frames, the details of the link beam and the fit of the other members must be done in such a way as to ensure its proper ductility. According to the obtained results, the performance of short link beams is much better than long link beams, and short link beams provide more energy dissipation and, at the same time, more ductility. Therefore, in the design of the link beam, mainly the shear of the link beam is considered as a ductile component. The axial force in the link beam, which is due to the application of lateral load to the structure, reduces both the bending capacity and the inelastic deformation capacity of the link beam, so it can be explained that in steel eccentric braces, the link beam is symmetrical between the two main components of the brace and it can affect the strength of the structure against lateral loads.

5

Investigation of the Occurrence of Progressive Collapse in High-Rise Steel Buildings with Different Braced Configurations

Saberi Hamid, Saberi Vahid, Sadeghi Abbasali, Pooyasefat Abbas, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 4

33--54

EN

The progressive collapse phenomenon refers to a chain of damages in a structure where all or a large part of the structure is destroyed by an initial local collapse in it, which can lead to very disastrous results. Therefore, the prevention of progressive collapse has become a necessary action in the design and analysis of buildings and it is vital to investigate this topic more accurately. This study aims to present a proposed pattern in the configuration of braces at the height of a high-rise steel building for reducing the probability of progressive collapse. In this regard, the vertical displacement of 18-story structure with four scenarios of column removal and five concentric bracing patterns including V, Inverted V, X, discontinuous X-bracing at height, and a combination of Xbracing in the side spans and discontinuous X-bracing at height in the middle spans are investigated and compared. In this study, the Alternative Path Method (APM) is used based on the GSA guideline for the analysis of progressive collapse. The results of this research showed that the use of X-bracing in the side spans and discontinuous X-bracing in the middle spans in nonlinear static and dynamic analyses performed better in reducing the probability of progressive collapse than other bracing configurations. Finally, it is recommended to use discontinuous X-bracing at the height that would place the bracings in one direction and providing alternative paths for force transferring in the structure.

6

Finite Element Modeling of Self-Compacting Concrete Beams Under Shear

Hosseinimehrab lham, Sadeghi Abbasali, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2021

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Vol. 31, no. 4

1--16

EN

Development of self-compacting concrete (SCC) is a very desirable achievement in the reinforced concrete (RC) structures for overcoming issues associated with many problems such as congestions of steel reinforcement. This non-vibrating concrete is not affected by the skill of workers, and the shape and amount of reinforcing bar arrangement of a structure. Due to the high fluidity and resisting power of reinforcing of SCC, it can be pumped longer distances. In this study, the finite element (FE) modeling of three SCC beams in shear while taking into account, the flexural tensile strength of concrete is computed and the results are compared with the available experimental tested reinforced SCC beams. The stirrups are located at 75 mm apart from the end of beams up to the loading point. The electrical strain gauges (ESGs) have been embedded on the stirrups and their strain readings are taken for every step of load increment. For modeling longitudinal steel reinforcing bars and concrete, the 3-D elements with 2-node and 8-node, are used respectively. The comparison of results obtained by two methods is indicated that a good satisfactory agreement is achieved.

7

Seismic Behavior of Earth Dams With Different Reservoir Water Levels Under Near-Field and Far-Field Earthquakes

Asadi Masoud, Soltani Fazlollah, Sinvandi-Pour Abbas, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 4

125--141

EN

The height of reservoir water is one of the important factors affecting the seismic behaviour of earth dams. A large number of earth dams have been constructed in different countries that are sometimes located in a high-risk geographical zone. The studies on the seismic behaviour of earth dams have been conducted for several decades. However, this study, considering the importance of the subject, it investigates the seismic behaviour of Sumbar rock-fill embankment dam under near- and far-field earthquakes with variation in the water level behind the dam. The ratio of water height of the dam to dam height is considered as an important indicator to investigate the seismic performance of these structures. The analyses were performed using the ABAQUS finite element platform, under 7 near-field and 7 far-field earthquake records. In this research, the changes in dam stresses, displacements, and failure of the dam have been discussed. The results indicated that the effect of near-field earthquakes on the seismic behaviour of earth dams is more significant than far-field earthquakes.

8

Reliability-based safety evaluation of the BISTOON historic masonry arch bridge

Pouraminian Majid, Pourbakhshian Somayyeh, Noroozinejad Farsangi Ehsan, Berenji Sevil, Keyani Borujeni Salman, Moosavi Asl Mirhasan, Mohammad Hosseini Mehdi

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 1

87--110

EN

This research examines the probabilistic safety assessment of the historic BISTOON arch bridge. Probabilistic analysis based on the Load-Resistance model was performed. The evaluation of implicit functions of load and resistance was performed by the finite element method, and the Monte-Carlo approach was used for experiment simulation. The sampling method used was Latin Hypercube. Four random variables were considered including modulus of elasticity of brick and in filled materials and the specific mass of brick and infilled materials. The normal distribution was used to express the statistical properties of the random variables. The coefficient of variation was defined as 10%. Linear behavior was assumed for the bridge materials. Three output parameters of maximum bridge displacement, maximum tensile stress, and minimum compressive stress were assigned as structural limit states. A sensitivity analysis for probabilistic analysis was performed using the Spearman ranking method. The results showed that the sensitivity of output parameters to infilled density changes is high. The results also indicated that the system probability of failure is equal to rhofsystem=1,55x10-3. The bridge safety index value obtained is betat=2.96, which is lower than the recommended target safety index. The required safety parameters for the bridge have not been met and the bridge is at the risk of failure.

9

Reliability assessment and sensitivity analysis of concrete gravity dams by considering uncertainty in reservoir water levels and dam body materials

Pouraminian Majid, Pourbakhshian Somayyeh, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 1

1--17

EN

An elaborate safety assessment of the Pine Flat (PF) concrete gravity dam (CGD) has been conducted in this paper. Structural analysis was performed by taking into account the uncertainties in the physical and mechanical properties of the dam body materials and the reservoir water level. The coefficient of variation of 5 and 10 percent and the Gaussian distribution (GAUS) are assigned to random variables (RVs). Sensitivity analysis (SA) of the RVs is done, and important parameters introduced. SA is done to identify the most influential RVs on the structural response. Also, the modulus of elasticity of concrete is the most effective parameter in response to horizontal deformation of the dam crest. The concrete density and US hydrostatic pressure height are the most effective parameters, and the Poisson's ratio is the insignificant parameter on the dam response. To be confident in the safety of the dam body under usual loading, including the dam weight and the upstream (US) hydrostatic pressure, the reliability index (RI) has been obtained by Monte Carlo simulation. The RI for the coefficients of variation of 5 and 10 percent were obtained at 4.38 and 2.47, respectively. If the dispersion of RVs is high, then the dam will be at risk of failure.

10

Application of buckling restrained braces to upgrade vertical stiffness of existing RC frames

Niyonyungu Ferdinand, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 3

68--93

EN

In this paper, based on the RC frame structure of an industrial building, the finite element model of the structure is developed, according to the Chinese code for seismic design of buildings [9]. Considering the lack of seismic performance, the buckling restrained brace (BRB) is adopted for seismic retrofitting, and various configurations of buckling restrained support are considered for reinforcement. The elastic response spectrum analysis (RSA) and direct integration nonlinear time history analyses (NL-TH) are carried out for the frame structure before and after reinforcement using ETABS finite element software. From the joints displacement, inter-story displacement, inter-story shear force, acceleration, energy dissipation, and other aspects of the seismic response of the strengthened structure and the non-strengthened structure, the comparison has been made. The effect of buckling restrained support and common support on the existing building structure is verified through analytical modeling. After reinforcement, there is a 40%, 39.3%, 40%, 36.4%, and 38.3% reduction in the first period of vibration after the building is strengthened by inverted BRB, V BRB, two-story BRB, single BRB, and ordinary steel braces, respectively. Strengthening of the structure by buckling restrained braces and ordinary steel braces both decrease the original building displacement by more than 50% from the first to the fourth floor. Under severe earthquakes, the use of BRB reduced the column shear by 46.6%; similarly, the incorporation of ordinary steel braces reduced the column shear by 4.72%. It is concluded that using buckling restrained braces will increase the vertical stiffness of the structure to a very high extent.

11

A Study on the Significance of the Design Parameters of Steel Plate Shear Walls Subjected to Monotonic Loading

Honarmand Saeed, Homami Peyman, Gharehbaghi Vahidreza, Noroozinejad Farsangi Ehsan

Civil and Environmental Engineering Reports

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2020

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Vol. 30, no. 4

142--154

EN

Steel plate shear walls (SPSWs) as a resistant system against lateral loads have a high potential for earthquake energy dissipation. Due to the uncertainties of loading, construction, and installation of SPSWs, it is vital to investigate the importance of each component and achieve higher accuracy in design and the implementation of these members. In this paper, a sensitivity analysis is carried out to determine the significance of important uncertainties. The results denoted that the most important parameters affecting the loading capacity of the SPSWs are height, thickness, length, Young's modulus of the wall material, flange, and web thickness of the column, respectively.

12

Seismic performance evaluation of a proposed buckling-restrained brace for RC-MRFS

Ebanesar Arunraj, Cruze Daniel, Noroozinejad Farsangi Ehsan, Seenivasan Vinscent Sam Jebadurai, Mohammad Adil Dar, Abdul Rashid Dar, Gladston Hemalatha

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 3

164--173

EN

This paper presents a novel buckling-restrained brace (BRB) where the inner core is restrained by a concrete infilled Expanded Polystyrene Sheet (EPS) instead of the conventional concrete infilled tube section, to resist inner core buckling. It serves two purposes, firstly, the EPS is a ductile material, which is favourable in terms of seismic performance and, secondly, the outer construction material has better corrosion resistance. Thus, the life of the steel core can be prolonged. In this study, 6 BRB specimens were prepared, of which 3 BRB specimens were infilled with concrete and the remaining 3 BRB specimens with concrete and EPSs, in order to study their performance under cyclic loading. Three different core heights, all with the same core thickness, were adopted. The test results indicate that the load-carrying capacity of this novel BRB is higher than the conventional BRB. Further, the length of the steel tube also affects the strength of the seismic disaster mitigation system. Lastly, a numerical study on a single bay RC frame, with and without BRB subjected to time history analysis, was conducted to check the global performance of this novel system. It was found that the structural responses had substantially decreased.

13

Probabilistic safety evaluation of a concrete arch dam based on finite element modeling and a reliability L-R approach

Pouraminian Majid, Pourbakhshian Somayyeh, Noroozinejad Farsangi Ehsan, Fotoukian Reza

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 4

62--78

EN

The safety assessment of the Pacoima arch dam is investigated in this paper. A Load – Resistance (L-R) method was used to ensure that the dam is safe or if it is at risk of failure. The "probabilistic design system" ANSYS finite element software was used to calculate the probability of failure. The Monte Carlo (MC) method with 50,000 iterations utilized for simulation and the Latin Hypercube method were used for Sampling. Input random variables with normal distribution and coefficient of variation of 15% due to uncertainties were considered and the six random variables used are the concrete modulus of elasticity, Poisson's ratio of concrete, concrete mass, up-stream normal water level of the reservoir, and the allowable tensile and compressive strength of the concrete. Linear elastic behavior was assumed for the constitutive law of concrete material and if the stress exceeds the allowable stress of the concrete this is considered as a failure limit state. The maximum and minimum principal stresses were considered as the output parameter. Dam body safety was investigated only under self-weight and upstream hydrostatic pressure at the normal water level [...]