@article { author = {}, title = {MONOTONIC BEHAVIOR OF GEOTEXTILE REINFORCED SOILS UNDER DISCRETE ROTATION OF PRINCIPAL STRESSES}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {325-335}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2412}, abstract = {Monotonic triaxial compression, triaxial extension and torsional shear tests werecarried out on geotextile reinforced sand and reinforced clay, mainly to investigate the effects ofrotation of principal stresses on the mechanical behavior of the reinforced soil materials. The testswere carried out on unreinforced and reinforced specimens with 2, 3 and 4 geotextile layers underthree different confining pressures. Investigation of the monotonic behavior of the reinforcedmaterials under different stress paths, i.e. triaxial compression, triaxial extension, and torsionalshear shows that direction of principal stresses can have profound effects on the stress-strain curve,shear strength, and slope and intercept of failure envelope. Test results reveal that geotextilesimprove the mechanical properties of the sand and clay, since both strain at failure and undrainedshear strength increase with the number of geotextile layers in sand and clay. In addition, testresults indicate that geotextile inclusion enhances the mechanical properties of geotextilereinforced sand and clay, however, geotextiles seems to be more effective when used to reinforcesands.}, keywords = {Principal stress rotation,geotextiles,sand,clay}, url = {https://ijstc.shirazu.ac.ir/article_2412.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2412_2620e03bbd0f12c337dbe2138fb468ae.pdf} } @article { author = {}, title = {STRUCTURAL RESPONSE OF REINFORCED CONCRETE WIDE BEAMS REINFORCED WITH LATTICE GIRDERS}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {337-344}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2413}, abstract = {This paper summarizes the test data obtained from an experimental investigation ofreinforced concrete (RC) wide beams reinforced with lattice girders, which can also be describedas one-way slabs, under low-rate (static) concentrated loading applied at their mid-span. Testswere conducted on lattice girder reinforced and traditionally reinforced beam-type specimens toinvestigate the effect of lattice girder on load carrying capacity. Key aspects of structural responsesuch as the load–deflection behavior, crack patterns, strength and failure modes of the testedbeams were recorded and given in this paper. A total of 6 beams with two different reinforcementarrangements were tested. Tested beams were simply supported at a span of 2250 mm. Allspecimens were tested under static loading and midspan deflections were recorded using adisplacement transducer. Similar stiffness was displayed by the lattice girder reinforced andtraditionally reinforced beams, but higher resistant capacity was shown by the lattice girderreinforced beams.}, keywords = {Lattice girder,load carrying capacity,reinforcement arrangement,reinforced concrete wide beam,structural response}, url = {https://ijstc.shirazu.ac.ir/article_2413.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2413_3e146d1b183554a0934b5d4416a48edb.pdf} } @article { author = {}, title = {SEISMIC BEHAVIOR OF EXTERIOR BEAM-COLUMN JOINT USING MECHANICAL ANCHORAGE UNDER REVERSAL LOADING: AN EXPERIMENTAL STUDY}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {345-358}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2414}, abstract = {In reinforced concrete structures, beam-column joints are one of the most criticalregions in the areas with moderate and severe seismic prone areas. Proper reinforcementanchorage is essential to enhance the performance of beam-column joints. Congestion ofreinforcement and construction difficulty is one of the critical problems while using conventionalreinforcement detailing in beam-column joints of concrete structures. An effort has been made tostudy and evaluate the performance of beam-column joints. The joints are detailed for higherseismic prone areas as per ACI-352 (Mechanical Anchorage), ACI-318 (Conventional HooksBent) and IS-456 (Full Anchorage Hooks Bent) along with confinement as per IS-13920 andproposed X-cross plus hair clip bar joint reinforcement. Apart from finding the solution to theseproblems, significant improvements in seismic performance, ductility and strength were observedwhile using mechanical anchorage in combination with X-cross plus hair clip bars. To assess theperformances of anchorages and joint details, the specimens were assembled into two groups ofthree specimens each. The specimens were tested under reversal loading and test results wereevaluated and presented in this paper.}, keywords = {Reinforced concrete structure,beam-column connection,mechanical anchorage,reversal loading}, url = {https://ijstc.shirazu.ac.ir/article_2414.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2414_a1ea6f999c0f1bd306f4c917f605e3a3.pdf} } @article { author = {}, title = {SEISMIC BEHAVIOR OF INTERNAL REINFORCED CONCRETE BEAM-COLUMN JOINTS: A DETAILED MODELING AND SIMULATION INVESTIGATION}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {359-376}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2415}, abstract = {In a Seismic Force Resisting System (SFRS), beam-column joints are crucial structuralelements. Failure of these elements may lead to total collapse of a structure. Recent earthquakeshave demonstrated that structural systems designed based on current codes of practice arevulnerable to sever damages, mostly due to undesirable performance of joints. In general, designcodes do not consider the effects of joint characteristics on the behavior of the structure and treatjoints as members which remain elastic during an earthquake. To thoroughly understand the effectsof different design parameters on the behavior of beam-column connections in RC structures andconsequently on the overall performance of SFRS, a wide range of experiments must be carriedout. But prior to a successful setup and conducting any experiments, a theoretical study andnumerical simulation is essential. Therefore, having some reliable F.E. models at our disposalplays a significant role in the field of experimental and theoretical research.This paper first explains, in detail, the process for developing a F.E. model for RC beamcolumnconnections in the simulation environment provided by ANSYS. Next an attempt is madeto study the behavior of RC beam-column joints subjected to seismic forces using the developedmodel. Finally, the effects of main joint characteristics including ductility, moment capacity ratio,type of loading, ultimate loads, over-strength factors and joint transverse reinforcement areinvestigated.}, keywords = {RC joint,ductility,over-strength factor,moment capacity,push-over,cyclic load,seismic force}, url = {https://ijstc.shirazu.ac.ir/article_2415.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2415_7ff09e88bf140e9981361d448b1a3ad1.pdf} } @article { author = {}, title = {FREE VIBRATION OF MOVING LAMINATED COMPOSITE PLATES WITH AND WITHOUT SKEW ROLLER USING THE ELEMENT-FREE GALERKIN METHOD}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {377-393}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2416}, abstract = {In this paper, free vibration of axially moving symmetrically laminated plates subjectedto in-plan forces is analyzed using the element-free Galerkin method. This category includessymmetric cross-ply and angle-ply laminates and anisotropic plates. The governing differentialequation for a moving plate is numerically solved using the Galerkin method. The shape functionsare constructed using the moving least squares (MLS) approximation and the essential boundaryconditions are introduced into the formulation through the use of the Lagrange multiplier methodand the orthogonal transformation techniques. The effect of skew roller and intermediate supportson the natural frequency of plate are examined.}, keywords = {Moving plate,element-free Galerkin method,laminated composite plate,skew roller,intermediate supports}, url = {https://ijstc.shirazu.ac.ir/article_2416.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2416_9b6b2417a7ee86160d56d22d316bb9d5.pdf} } @article { author = {}, title = {PROPOSED EQUATIONS FOR ESTIMATING THE FLEXURAL CHARACTERISTICS OF REINFORCED HPFRCC BEAMS}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {395-407}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2417}, abstract = {HPFRCC materials are a class of cement composites with fine aggregates that exhibitstrain hardening behavior under tensile loading. This strain hardening response occurs after thefirst cracking of the material. In this paper, experimental and theoretical studies were conducted toassess the influence of using HPFRCC material instead of normal concrete in RC beams. Thetheoretical results for simply supported beams with different values of compressive strengths arepresented and compared with the available experimental data. Results indicate that using HPFRCCmaterial instead of normal concrete in RC beams concludes to more ultimate load, deflection andductility compared to normal reinforced concrete beams. Moreover, new theoretical equations areproposed for estimating the flexural characteristics of reinforced composite and reinforcedHPFRCC beams. Results show that the flexural capacity of reinforced HPFRCC beams is about6.4% higher than that of RC beams. Moreover, flexural capacity of experimental reinforcedHPFRCC beams is about 11.2% higher than that of theoretical values.}, keywords = {Concrete,HPFRCC,flexural capacity,ultimate deflection,ultimate load}, url = {https://ijstc.shirazu.ac.ir/article_2417.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2417_01659b756b5ec19579ae7ef9d917f91d.pdf} } @article { author = {}, title = {QUANTITATIVE ASSESSMENT AND STATISTICAL ANALYSIS OF MEDICAL WASTE GENERATION IN DEVELOPING COUNTRIES: A CASE STUDY IN ISFAHAN (IRAN)}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {409-420}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2418}, abstract = {Quantitative assessment and statistical analysis of medical waste generation atprovincial scale in Isfahan was conducted. Results indicated that 59% of the total wastes producedwere non-hazardous (general) wastes and the rest were hazardous medical wastes. More than 98%of centers implemented source separation of the wastes at source. Also, more than 91% had astorage room, but only 48% of storage rooms were operated under standard conditions, i.e. storagewith appropriate ventilation and temperature control. Only about 21% of medical centers haddesignated collection vehicles. For the remaining 79% of facilities, the medical wastes werecollected (comingled) and transported together with the general or non-medical wastes. As for thetreatment of medical wastes, only 7% of centers were equipped with autoclave. Although 22% ofcenters had incinerators, the majority of them were not functional. Collected wastes from 29% offacilities were disposed together and mixed with the municipal wastes at the same landfilltrenches. Wastes from the remaining 71% of centers were landfilled in separate trenches. Thewaste generation rates for total waste and general (non-hazardous) waste were 3.03 and 1.84kg/active beds/day, and 1.03 and 0.65 kg/employees/day, respectively. Using multivariateregression analysis of data an empirical equation (Y = 0.55 * NEM + 1.44 * NAB) was establishedto predict the total amount of waste generated at each facility (Y) as a function of number of activebeds (NAB) and number of employees (NEM) of the facility. Strong correlation (R2 = 0.97)between the observed and predicted values was observed.}, keywords = {Health care,medical,hazardous,waste,waste audit,developing countries}, url = {https://ijstc.shirazu.ac.ir/article_2418.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2418_9216d0a563d024c0edad2e847dd29774.pdf} } @article { author = {}, title = {EVALUATION OF SEVERAL REFERENCE EVAPOTRANSPIRATION METHODS: A COMPARITIVE STUDY OF GREENHOUSE AND OUTDOOR CONDITIONS}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {421-437}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2419}, abstract = {Precise estimates of reference evapotranspiration (ET0) are necessary for theapplication of irrigation design and scheduling. Numerous empirical methods for predicting ET0are available, but their accuracy under different environmental conditions is uncertain. Greateruncertainty exists under greenhouse conditions because these methods were designed to apply tofield situations, and greenhouses have an effect on the temperature, humidity and wind, etc. In thisstudy, the results of 13 different common daily ET0 estimation methods, namely FAO56 Penman –Monteith, Hargreaves-Samanι, FAO-24 Blaney-Criddle, FAO-24 Radiation, Priestley-Taylor,Makkink, Turc, Linacre, Jensen-Haise, Copais, Pan Evaporation, Rn-radiation and Rs-radiation arecompared with lysimetric measurements in an area of Fars (Badjgah) in a plastic greenhouse toprovide helpful information for selecting the appropriate ET0 equation to use. In addition to dailyvalues, smoothed daily and mean 10-day ET0s were estimated to study the effect of daily weatherdata fluctuations on the precision of predictions. Performances of ET0 methods are evaluated byfour statistical criteria along with regression indices. The results indicate that FAO Penman-Monteith and Linacre are the most and the least appropriate methods for estimating daily ET0 ingreenhouse conditions, respectively. For outdoor conditions the best and worst results wereobtained from FAO24- Radiation and Copias methods, respectively. Smoothing weather data, gavebetter regression fits for FAO Penman-Monteith and FAO24-Radiation methods for bothgreenhouse and field conditions than those for daily weather data. Better predictions were obtainedfor field than greenhouse conditions. The total ET0 values in greenhouse were about 0.85 of thosemeasured in outdoor lysimeters.}, keywords = {Estimation methods,microlysimeter,performance evaluation,smoothed data}, url = {https://ijstc.shirazu.ac.ir/article_2419.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2419_2b13f2e88fb855fd2195a237da55a3d7.pdf} } @article { author = {}, title = {STRUCTURAL RELIABILITY ANALYSIS USING CHARGED SYSTEM SEARCH ALGORITHM}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {439-448}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2420}, abstract = {This paper focuses on the design point and the failure probability of problems withcontinuous random variables. The charged system search (CSS) algorithm is utilized as theoptimization tool to achieve minimum reliability index under limit state function. In order toacquire the optimal solution, random variables such as elastic modulus, loads, and geometricparameters are selected as decision variables of the problem which are optimized by means of theCSS algorithm. This algorithm is inspired by the Coulomb and Gauss’s laws of electrostatics fromphysics. In order to evaluate the accuracy and efficiency of this algorithm, several numericalexamples are studied and the results are compared to those of the existing methods.The proposed method is capable of finding a design point over the failure surface and calculatesthe reliability index with a reasonable accurately. As the proposed framework enforces lowcomputational time and holds a satisfactory convergence rate, it is a competent methodology tocalculate different types of reliability problems.}, keywords = {Structural reliability,Optimization,charged system search,limit state function,failure probability,design point}, url = {https://ijstc.shirazu.ac.ir/article_2420.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2420_4bebe981b7a6d56f6b5d81b9621ffe19.pdf} } @article { author = {}, title = {ESTIMATION OF FLOW DISCHARGE UNDER THE SLUICE AND RADIAL GATES BASED ON CONTRACTION COEFFICIENT}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {449-463}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2421}, abstract = {Sluice and radial radial gates are common devices used for flow control in hydraulicstructures. This paper demonstrates the variation of the contraction coefficient of sluice gates andthree types of radial gates (namely, Hard-Rubber, Sharp and Music Note gates) by using Energyand Momentum Equations (EMEs). This paper presents a novel method for estimating the actingforce behind these gates under free and submerged flow conditions. A minimum value of thecontraction coefficient for sluice gates was obtained under a certain value of relative gate opening.Under a specific condition, Hard-Rubber gates have a larger contraction than Sharp gates, whileMusic Note gates have the least contraction. It is recognized that the contraction coefficientdecreases as the gate lip angle and the gate opening increase. Under submerged flow conditions,the contraction coefficient of sluice and radial gates would be either increased or decreaseddepending on the level of flow submergence. It is concluded that using the proposed contractioncoefficient in estimating the discharge coefficient demonstrates an acceptable accuracy.}, keywords = {Sluice gate,radial gate,contraction coefficient,discharge measurement}, url = {https://ijstc.shirazu.ac.ir/article_2421.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2421_32b6cdd40293ccc0ee005b301ba63eb5.pdf} } @article { author = {}, title = {SEISMIC PERFORMANCE OF SLOPES IN PSEUDO-STATIC DESIGNS WITH DIFFERENT SAFETY FACTORS}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {465-483}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2422}, abstract = {Seismic coefficient values coupled with minimum pseudo-static safety factors are stillused for analysis where selection of seismic coefficients relies on expertise and judgment.However, safety factor approach does not give any idea about the deformations and displacementsthat are expected to occur during earthquake loading. Displacements are mostly evaluated byequations based on yield acceleration of the slope and maximum acceleration of sliding mass. Themethod based on rigid block gives co-seismic permanent slope deformation when its factor ofsafety equals 1.0, hence, there is a need to link slope displacements, seismic coefficients andpseudo-static safety factors. This will enable the designers to predict slope displacements based onselected seismic coefficients. In the present paper, slope displacements obtained for different peakground accelerations and safety factors are used to propose charts linking co-seismic slopedisplacements (D), seismic coefficients (􀝇􀯛) and pseudo-static safety factors (FS), which areimportant parameters in pseudo-static approach. This enables the 􀝇􀯛 values to be chosen based onallowable displacements instead of using judgment and expertise. Results show that 􀝇􀯛 values forany allowable displacement should be based on anticipated PGA and FS values. Subsequently,slope displacements are utilized in developing a novel displacement-based methodology to selectthe seismic coefficient which will be used to calculate the pseudo-static safety factor.}, keywords = {Slope stability,slope,displacement,Performance,seismic coefficients}, url = {https://ijstc.shirazu.ac.ir/article_2422.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2422_19c4b64cd71982046acdf750ee4cf0b4.pdf} } @article { author = {}, title = {ANALYSIS OF THREE-DIMENSIONAL CONSOLIDATION OF UNSATURATED SOILS}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {485-493}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2423}, abstract = {This study extends the theory of three-dimensional consolidation to unsaturated soilsand formulates the theory for finite element analysis by treating the pore water and pore air as amixed pore fluid. This formulation considers variations in the permeability and compressibility ofthe mixed pore fluid with changes in the void ratio and degree of saturation. The compressibility ofthe mixed pore fluid is derived using Boyle’s Law. An example of the settlement of a verticaldrain is investigated and discussed; this example demonstrates that the numerical analysis theory isapplicable and reliable. The results indicate that the rate of consolidation of unsaturated soils isclearly slower than that of saturated soils, the rate of dissipation of the pore fluid pressure isconsiderably slower, and the permeability of the mixed pore fluid decrease during consolidation.This theory is applicable to unsaturated soils with high degrees of saturation and can be used toobtain more reliable predictions of unsaturated soil consolidation.}, keywords = {Unsaturated soils,consolidation theory,pore fluid,finite element,vertical drain}, url = {https://ijstc.shirazu.ac.ir/article_2423.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2423_01d99754ba3a8bcb1ab100827566152a.pdf} } @article { author = {}, title = {NEW CANONICAL FORMS FOR THE ANALYSIS OF SYMMETRIC TRUSS STRUCTURES}, journal = {Iranian Journal of Science and Technology Transactions of Civil Engineering}, volume = {38}, number = {C2}, pages = {495-503}, year = {2014}, publisher = {Shiraz University}, issn = {2228-6160}, eissn = {}, doi = {10.22099/ijstc.2014.2424}, abstract = {For a symmetric structure the degrees of freedom (DOFs) in two sides of the axis ofsymmetry can be either symmetric or anti-symmetric. If there is no active DOF on the axis ofsymmetry, then we will have the Form II symmetry for the structural matrices, and alternatively ifwe have some active DOFs on the axis, we will have Form III symmetry. These forms are alreadydeveloped and employed in structural dynamics and stability analysis of frame structures.However, for the structures having both symmetric DOFs and anti-symmetric DOFs,simultaneously, we will have different canonical forms, defined in this paper as the Form A andForm B symmetry. Thus the main objective is to develop these forms and explore the governingrelationships. The presented method is then applied to the analysis of symmetric structures.}, keywords = {canonical forms,symmetry and anti-symmetry,trusses,form A,form B}, url = {https://ijstc.shirazu.ac.ir/article_2424.html}, eprint = {https://ijstc.shirazu.ac.ir/article_2424_a3c8ce9aa0102fea5e8efc82d30e013f.pdf} }