NATIONAL CONGRESS ON CIVIL ENGINEERING | Year:2016 | دوره:9 |Papers Count:26

REGARDING DEVELOPMENTS IN COMPUTATIONAL HARDWARE, IT WAS BASICALLY REBIRTH FOR SMOOTHED PARTICLE HYDRODYNAMICS (SPH) AS A LAGRANGIAN, MESHLESS, NUMERICAL METHOD. SPHYSICS IS ONE OF THE BEST OPEN SOURCE CODES BASED ON THIS METHOD. NOTWITHSTANDING THE BENEFITS OF THE SOFTWARE, IT STILL NEEDS TO BE DEVELOPED FOR MODELLING DIFFERENT PHENOMENA.IN THIS PAPER, BY MEANS OF A BERM BREAKWATER AS AN OBSTACLE, A NUMERICAL FLUME WITH A PROGRESSIVE WAVE, IN SPHYSICS HAS BEEN SIMULATED. THE VARIATION IN WATER PROFILE AND OTHER FLOW PARAMETERS HAS BEEN MONITORED. MEANWHILE, A FINITE VOLUME SOFTWARE SIMULATION, IS THE MAIN COMPARISON TOOL TO CHECK NUMERICAL RESULTS OF BOTH MODELS. BY COMPARING FINITE VOLUME MODEL WITH SPH MODEL, THE MODELS HAVE BEEN VERIFIED. ALSO THE SPH METHOD ACCURACY, REGARDING ITS BASICS AND ORIGINAL CHARACTERISTICS, MAY NOT EXACTLY MEET OTHER COMMON COMPUTATIONAL METHODS YET, BUT IT SURELY CAN PAVE THE WAY FOR SIMULATING NATURAL PHENOMENA IN RESEARCHES.

DIAGRID STRUCTURAL SYSTEM IS A PARTICULAR FORM OF TUBULAR SYSTEMS, WHICH EXTERIOR COLUMNS REPLACED BY DIAGONAL MEMBERS. THIS SYSTEM CONTAINED OF DIAGONAL TRUSS ELEMENTS THROUGH THE HEIGHT OF THE STRUCTURE.THE STABILITY AND SHEAR RIGIDITY OF DIAGRID SYSTEM IS DUE TO AXIAL PERFORMANCE OF DIAGONAL ELEMENTS. THIS PAPER CONTROLS A SIMPLE METHODOLOGY FOR ANALYZING THE INTERNAL FORCES ARISING IN THE SINGLE DIAGRID MODULE DUE TO VERTICAL AND HORIZONTAL LOADS, THE RESISTING MECHANISM OF DIAGRID STRUCTURES UNDER GRAVITY AND EARTHQUAKE LOADS IS DESCRIBED. THE METHODOLOGY IS APPLIED TO A DIAGRID STRUCTURE. TO THIS END, A 36-STROEY DIAGRID STRUCTURE WITHOUT CORNER COLUMNS WAS DESIGNED, AND THEN A COMPARATIVE ANALYSIS CARRIED OUT. THE ANGLE OF DIAGONAL ELEMENTS THROUGH THE HEIGHT OF THE STRUCTURE IS CONSIDERED 67.38 DEGREES AND THE PLAN OF STRUCTURE IS SQUARE. INTERNAL FORCES DUE TO GRAVITY AND LATERAL LOADS IN DIAGRID ELEMENTS SHOWED ENOUGH CORRESPONDENCE BETWEEN FINITE ELEMENT ANALYSIS AND HAND CALCULATION. THE RESULTS SHOWED THAT THIS METHODOLOGY IS USEFUL FOR PRELIMINARY DESIGN AND ACCESSING THE INTERNAL FORCES.

IN THIS PAPER NUMERICAL STUDY OF BEHAVIOR OF SIMPLY SUPPORTED RC SLAB SUBJECTED TO BLASTING IS PRESENTED. TO ACCOMPLISH THIS TASK, ABAQUS 6-12 SOFTWARE, CAPABLE OF PERFORMING NONLINEAR ANALYSIS, WERE USED. USING AVAILABLE EXPERIMENTAL DATA, AND WITH A REVERSE ENGINEERING PROCESS, APPROPRIATE BEHAVIORAL MODEL FOR CONCRETE, REBAR AND EXPLOSIVES WERE ADOPTED AND THE DETAIL OF MODELING WAS VERIFIED. AFTER VERIFICATION, THE EFFECT OF EXPLOSION DEPTH AND CHARGE MASS, KEEPING CONSTANT THE SLAB SIZE AND CONCRETE GRADE WERE INVESTIGATED. IT WAS SHOWN THAT INCREASING THE EXPLOSION DEPTHS BEYOND 0.2 M LEADS TO AN INCREASE IN THE DAMAGE ON FRONT AND BACK SURFACES AND THE CRATER IN BACK SURFACE WHILE THE CRATER DIAMETER ON THE FRONT SURFACE DECREASES. IT WAS ALSO SHOWN THAT THE SIZE OF DAMAGE AND CRATER INCREASES ALMOST LINEARLY WITH INCREASING THE MASS OF TNT, KEEPING THE CHARGE DEPTH FIXED.

LIQUEFACTION EVALUATION METHODS IN SANDY SOILS IS GENERALLY BASED ON THE DETERMINISTIC ANALYSIS. IN THE DETERMINISTIC APPROACH, CERTAIN AND NON-DISPERSION PARAMETERS ARE CONSIDERED. FURTHERMORE, IN THESE METHODS, ESTABLISHMENT OF EXACT CORRELATION BETWEEN THE PROBABILITY OF LIQUEFACTION (PL) AND THE FACTOR OF SAFETY (FS) IS NOT POSSIBLE. THIS PROBLEM IS SOLVED USING THE RELIABILITY ANALYSIS. IN THIS PAPER, EFFECT OF THE PARAMETER UNCERTAINTY IN LIQUEFACTION PROBABILITY, BASED ON THE GENE EXPRESSION PROGRAMMING (GEP) MODEL FOR LIQUEFACTION RESISTANCE AND POTENTIAL EVALUATION BASED ON STANDARD PENETRATION TEST (SPT) IS INVESTIGATED. IN ORDER TO VERIFY THE MODEL, GEP RESULTS ARE COMPARED WITH THE RESULTS BASED ON IDRISS AND BOULANGER APPROACH (2010). THEN, FIRST-ORDER RELIABILITY METHOD (FORM) BY USING A HYBRID OF PARTICLE SWARM OPTIMIZATION AND GENETIC ALGORITHM (PSO-GA) IN MATLAB2013A, AS A ROBUST OPTIMIZATION METHOD IS USED TO DETERMINE THE RELIABILITY INDEX (B). BAYESIAN MAPPING FUNCTION IS UTILIZED TO INFER THE RELATIONSHIP BETWEEN PROBABILITY OF LIQUEFACTION AND RELIABILITY INDEX. FINALLY, EFFECT OF THE LEVEL OF PARAMETER UNCERTAINTY ON THE LIQUEFACTION PROBABILITY BY DEVELOPMENT THE BAYESIAN MAPPING FUNCTIONS, ARE INVESTIGATED BY USING THE B-PL CURVES.

SOIL NAILING-ANCHORS METHOD HAS MANY ADVANTAGES RATHER THAN SOIL NAILING IN THE REINFORCEMENT OF GROUND SLOPES. IN THIS PAPER BEHAVIORAL COMPARISON OF SOIL NAILING-ANCHOR SYSTEM WITH SOIL NAILING USING A SMALLSCALED PHYSICAL MODEL WAS STUDIED. COMPOSITE SOIL NAILING-ANCHOR INCLUDING TWO ROW NAILS AND ONE ROW ANCHORS HAS BEEN UNDERTAKEN IN ORDER TO STABILIZE THE EXCAVATED WALL. AFTER EACH STEP OF EXCAVATING THE MODEL AND DURING LOADING THE REGION ADJACENT THE EXCAVATED WALL, DIGITAL PHOTOGRAPHS WERE TAKEN. USING IMAGE PROCESSING ON SEQUENCES OF DIGITAL IMAGES, BEHAVIOR OF REINFORCED SOIL WAS OBSERVED. THE RESULTS SHOW THAT MAXIMUM HORIZONTAL DISPLACEMENT OF FACING IN THE CASE OF COMPOSITE SOIL NAILING OCCURS IN LOWER PART OF WALL; THOUGH IN THE SOIL NAILING SYSTEM IT OCCURS IN TOP OF EXCAVATED WALL.

IN THE PROCESS OF DESIGNING A TYPICAL STRUCTURE, DUE TO THE CONCEPT OF OVERSTRENGTH, IT IS ASSUMED THAT THE STRUCTURE IS ABLE TO DISSIPATE THE SEISMIC ENERGY THROUGH INELASTIC BEHAVIOR. SO AS NOT TO OVERESTIMATE THE SEISMIC LOADS, WHICH RESULTS IN OVERDESIGNED MEMBERS, THE APPLIED LOADS SHOULD BE DIVIDED BY A FACTOR NAMED AS "RESPONSE MODIFICATION FACTOR" OR "R FACTOR." WITH RESPECT TO PRECAST STRUCTURES, MOST OF THE DESIGN CODES HAVE NOT PROPOSED A SPECIFIC RESPONSE MODIFICATION FACTOR AND MUCH MORE RESEARCH MUST BE CONDUCTED. IN THIS PAPER, THREE DIFFERENT TYPES OF STRUCTURES ARE DESIGNED IN THE COMMON WAY AND ALSO MODELED BY THE USE OF A SIMPLIFIED MODEL (INCLUDING BEAMS, COLUMNS, AND SPRINGS) IN THE SOFTWARE ABAQUS. SEVERAL NONLINEAR STATIC (PUSHOVER) AND NONLINEAR DYNAMIC TIME-HISTORY ANALYSES ARE PERFORMED USING THE HORIZONTAL COMPONENTS OF REAL EARTHQUAKES. AFTERWARDS, THE SEISMIC BEHAVIOR OF PRECAST REINFORCED CONCRETE (RC) MOMENT-RESISTING FRAMES ARE INVESTIGATED. THE RESPONSE MODIFICATION FACTORS OF THE DESIGNED STRUCTURES ARE CALCULATED FROM THE RESULTS OF THE NONLINEAR STATIC ANALYSES. THE RESULTS OF THE NONLINEAR DYNAMIC TIME-HISTORY ANALYSES ARE ALSO USED TO DETERMINE THE R FACTORS. FINALLY, A COMPARISON IS DRAWN BETWEEN BOTH OF THESE METHODS. EVENTUALLY A RESPONSE MODIFICATION FACTOR OF 6 IS SUGGESTED FOR THESE KINDS OF STRUCTURES.

IN THIS STUDY, THE DYNAMIC MOTIONS OF A RECTANGULAR CHAIN-MOORED FLOATING BREAKWATER WITH THREE DEGREES OF FREEDOM (HEAVE, SWAY, AND ROLL MOTIONS) ARE SIMULATED USING A WEAKLY-COMPRESSIBLE SMOOTHED PARTICLE HYDRODYNAMIC (WCSPH) SCHEME. A REGULAR WAVE IS SIMULATED USING A PISTON TYPE WAVE MAKER INSIDE A NUMERICAL WAVE FLUME. THEN, A RECTANGULAR MOORED FLOATING BREAKWATER IS PLACED INSIDE THE DEVELOPED NUMERICAL WAVE FLUME AND THE DYNAMIC MOTIONS OF THE STRUCTURE ARE RECORDED. IN THE DEVELOPED NUMERICAL SCHEME, THE WAVE-STRUCTURE AND MOORING-STRUCTURE INTERACTIONS ARE EVALUATED BY SOLVING NEW SPH-BASED EQUATIONS. IN ADDITION, THE MOORING SYSTEM IS SIMULATED BY THE SPH PARTICLES. COMPARING THE OBTAINED RESULTS FROM THE DEVELOPED SPH SCHEME WITH THE EXPERIMENTAL DATA REVEALS THAT THE MODIFIED SMOOTHEDPARTICLE HYDRODYNAMIC SCHEME IS ABLE TO SIMULATE THE DYNAMIC MOTIONS OF A CHAIN-MOORED FLOATING BREAKWATER WITH A REASONABLE ACCURACY.

WIDELY DISTRIBUTED 111 SERIE, 10 STORY R.C. FRAME BUILDINGS ARE CONSTRUCTED DURING FORMER SOVIET UNION IN ARMENIA AND NAGORNO KARABAKH PROVINCE. CURRENT RESEARCH IS COMPLETED TO ILLUSTRATE THE CONCEPT OF SEISMIC UPGRADING OF ABOVE MENTIONED BUILDINGS, USING AN ADDITIONAL ISOLATED UPPER FLOOR (AIUF). AFTER CONSTRUCTING THE FINITE ELEMENT MODEL, TIME HISTORY ANALYSES ARE APPLIED ON IT, USING SIX PAIR OF ACCELEROGRAMS RECORDED ON ROCK OR VERY STIFF SOIL (750<VS<1200 M/S), AND LOOSE ROCK OR STIFF SOIL (375<VS<750 M/S), SCALED TO SA=0.4G. LATER, THE AIUF WHICH BEHAVES AS A TUNED MASS DAMPER (TMD) IS ADDED TO THE MODEL AND AFTER TUNING FOR THE FREQUENCY AND DAMPING RATIOS, THE SAME TIME HISTORY ANALYSES ARE APPLIED ON THIS NEW MODEL TOO. THE FINAL ANALYSES RESULTS SHOW CONSIDERABLE REDUCTION ON LATERAL DISPLACEMENT AND BASE SHEAR FORCE WHEN USING AIUF, SATISFYING THE OVERALL SEISMIC BEHAVIOR OF THE BUILDING.

BASED ON THE LINEAR NATURE OF WATER CONVEYANCE PROJECTS, THEY INCLUDE VARIOUS GEOLOGICAL FORMATIONS AND ARE USUALLY IN CONTACT WITH WATER. BECAUSE OF THESE REASONS, MOST OF THE CONSTRUCTED IRRIGATION AND DRAINAGE NETWORKS ARE SUBJECT TO DEFORMATION AND DISPLACEMENT DUE TO PROBLEMATIC SOILS. ONE OF THESE PROBLEMATIC BEDS IS UNSATURATED EXPANSIVE SOIL. THE UNREINFORCED TRAPEZOIDAL CANALS ARE DAMAGED WHEN CONSTRUCTED ON THIS TYPE OF SOILS. IN THE CURRENT PAPER, THIS PHENOMENON HAS BEEN STUDIED USING FIELD OBSERVATIONS, EXPERIMENTAL TESTS, AND NUMERICAL MODELING. IN PRACTICE, A FILTER LAYER IS USED TO REDUCE THE SOIL SWELLING EFFECTS ON CANAL LINING IN TABRIZ PLAIN PROJECT. FOR PERFORMANCE INVESTIGATION OF THIS LAYER, THE AMOUNT OF SOIL SWELLING AND RELATIVE DISPLACEMENT OF CANAL SECTION PANELS ARE MEASURED BY RECORDING OF SURVEYING POINTS. THIS PHENOMENON IS ALSO MODELED NUMERICALLY. USING THE OBTAINED RESULTS, THE SWELLING OF THE BED SOIL IS CALCULATED AT DIFFERENT PARTS OF THE CANAL SECTION WITH FILTER AND WITHOUT IT AND THE LOCATIONS OF MAXIMUM MOVEMENTS ARE DETERMINED. IN ORDER TO PREDICT THE INTERACTION BEHAVIOUR BETWEEN UNSATURATED EXPANSIVE SOIL AND CONCRETE LINING AT DIFFERENT MOISTURE CONDITIONS, THE SPECIAL CONSTITUTIVE UNSATURATED SOIL BEHAVIOUR MODEL IS SELECTED IN SOFTWARE. THE RESULTS OF ANALYSIS SHOW THE LOCATION OF MAXIMUM DEFORMATION AND LINING BENDING MOMENT ON THE CANAL SECTION. IN ADDITION, COMPARISON BETWEEN THE RESULTS OF NUMERICAL MODELING AND FIELD DATA ILLUSTRATES ACCEPTABLE PRECISION OF THE NUMERICAL MODELING.

IN RECENT DECADES MANY RESEARCHERS HAVE STUDIED ON THE DAMAGE ASSESSMENT OF STRUCTURES AFTER A SEISMIC EVENT. TO ASSESS THE DAMAGE OF STRUCTURES AFTER AN EARTHQUAKE, IT IS SO IMPORTANT TO STUDY THE CORRELATIONS BETWEEN EARTHQUAKE PARAMETERS AND DAMAGES OF THE STRUCTURES. VARIATION OF FUNDAMENTAL PERIOD IS ONE OF THE METHODS TO IDENTIFY THE DAMAGE OF THE STRUCTURES. IN THIS PAPER CORRELATION BETWEEN EARTHQUAKE PARAMETERS AND VARIATION OF FUNDAMENTAL PERIOD IS STUDIED.TO CHARACTERIZE A SEISMIC EVENT, A LOT OF PARAMETERS HAVE BEEN DEFINED. IN THIS PAPER SEVERAL EARTHQUAKE PARAMETERS ARE CHOSEN TO STUDY. TWO RC FRAMES ARE ANALYZED UNDER FAR-FAULT EARTHQUAKE RECORDS BY NONLINEAR DYNAMIC ANALYSES. THE CORRELATIONS BETWEEN EARTHQUAKE PARAMETERS AND VARIATION OF FUNDAMENTAL PERIODS ARE CALCULATED. THE RESULTS SHOW THAT SOME OF THE EARTHQUAKE PARAMETERS HAVE HIGH CORRELATIONS WITH VARIATION OF FUNDAMENTAL PERIOD. THE MOST CORRELATIONS ARE FOR THOSE EARTHQUAKE PARAMETERS WHICH SOME RESEARCHERS HAVE SHOWN HIGH CORRELATIONS BETWEEN DAMAGE INDEXES OF STRUCTURES AND THEM. SO SOME EARTHQUAKE PARAMETERS WHICH HAVE HIGH CORRELATIONS WITH VARIATION OF FUNDAMENTAL PERIOD CAN BE PROPER INDICES TO ESTIMATE THE DAMAGE POTENTIAL OF AN EARTHQUAKE.

PEOPLE EMERGENCY EVACUATION AND ESPECIALLY EVACUATION TIME IN A DISASTROUS CONDITION SUCH AS AN EARTHQUAKE AND FIRE ARE OF GREAT IMPORTANCE. HERE WE OBSERVED EVACUATION BEHAVIOR OF ASSEMBLY HALL OF HUMANITIES FACULTY OF AZARBAIJAN SHAHID MADANI UNIVERSITY (ASMU). SIMULATIONS ARE DONE BY USING DISTINCT ELEMENT METHOD (DEM). IN DEM, PEOPLE ARE CONSIDERED AS CIRCULAR ELEMENTS AND ANALYSIS CAN COMPUTE THE POSITION OF EACH PERSON (ELEMENT) STEP BY STEP BY SOLVING THE EQUATIONS OF MOTION. FOUR CASES WITH DIFFERENT NUMBER AND ARRANGEMENT OF PEOPLE ARE CONSIDERED IN WHICH THE NUMBER OF PEOPLE WERE 350, 400, 450 AND 500 FOR CASES 1 TO 4, RESPECTIVELY. AS THE EVALUATION CRITERIA, PART THREE OF NATIONAL BUILDING REGULATIONS OF IRAN "BUILDING FIRE PROTECTION" IS ADOPTED IN WHICH THE NOMINAL EVACUATION TIME LIMIT FOR THIS KIND OF CONFINED SPACE IS CONSIDERED TO BE 200 SEC. EVACUATION SIMULATIONS ARE DONE FOR CONSIDERED CASES AND EVACUATION BEHAVIOR AND TIME ARE CALCULATED QUANTITATIVELY. EVACUATION TIMES ARE DETERMINED TO BE 173, 174, 184 AND 184 SEC FOR CASES 1 TO 4, RESPECTIVELY. AS RESULTS SHOW, IN ALL CONSIDERED CASES, EVACUATION TIME IS BELOW THE CODE LIMIT AND EVACUATION BEHAVIOR OF THE ASSEMBLY HALL BY CONSIDERING THIS CRITERION IS ACCEPTABLE.

SIMULATION OF FLUID FLOW IN PIPE NETWORK DISTRIBUTION SYSTEMS IS CONSIDERED TO BE A CLASSIC ENGINEERING PROBLEM IN FLUID MECHANICS AND HYDRAULIC ENGINEERING. AS A GENERAL RULE, THE ANALYSIS AND SIMULATION IS INTENDED TO PROVIDE VELOCITY AND PRESSURE FIELDS. THE CORRESPONDING FIELDS WOULD PROVIDE THE REQUIRED DATA TO DESIGN A VARIETY OF NETWORKS INCLUDING WATER NETWORK DISTRIBUTION, DRIP IRRIGATION NETWORK, OIL DISTRIBUTION AND VENTILATION FACILITIES, ETC. THE BASIC HYDRAULIC EQUATIONS FOR ANALYZING SUCH NETWORKS ARE CONTINUITY AND ENERGY EQUATIONS LEADING INTO A SYSTEM OF NONLINEAR SIMULTANEOUS ALGEBRAIC EQUATIONS IN TERMS OF DISCHARGE IN EACH PIPE OR HYDRAULIC HEAD AT EACH NODE AND/OR DISCHARGE CORRECTION IN EACH LOOP. THE RESULTING SYSTEM IS NONLINEAR AND DEMANDS FOR INTELLIGENT SELECTION OF INITIAL GUESS. THE CURRENT LITERATURE ON APPROPRIATE SELECTION OF INITIAL GUESS IS QUITE VAGUE AND DOES NOT CONSIDER THE OVERALL CONFIGURATION OF NETWORK INCLUDING ITS TOPOLOGY (I.E., PIPE LENGTH AND DIAMETER), TOPOGRAPHIC VARIATIONS, ETC. IN THE CURRENT PAPER, IT IS HYPOTHESIZED THAT WISE AND LOGICAL SELECTION OF INITIAL GUESS WITH DUE CONSIDERATION ON NETWORK TOPOLOGY AND TOPOGRAPHIC VARIATIONS (PARTICULARLY FOR LARGE NETWORKS) WILL ENHANCE THE CONVERGENCE RATE AND REDUCE THE NUMBER OF ITERATIONS REQUIRED TO REACH THE FINAL STEADY STATE SOLUTION. FOR THIS PURPOSE, AT THE START OF SIMULATION, THE FLOW REGIME IS CONSIDERED TO BE LAMINAR WHICH WILL RESULT IN LINEAR RELATIONSHIP BETWEEN VELOCITY AND PRESSURE FIELDS. INCORPORATION OF THIS ASSUMPTION LEADS TO A SYSTEM OF LINEAR SIMULTANEOUS ALGEBRAIC EQUATIONS WHICH OBVIOUSLY DOES NOT REQUIRE ANY INITIAL GUESS AND WILL TAKE INTO ACCOUNT NETWORK TOPOLOGY AND TOPOGRAPHIC VARIATIONS. FINITE ELEMENT METHOD IS USED TO CAST AND SOLVE THE RESULTING SYSTEM ASSOCIATED WITH LAMINAR FLOW REGIME ASSUMPTION. THE RESULTING SOLUTION FOR HYDRAULIC HEAD AT EACH NODE AND DISCHARGE IN EACH PIPE IS UTILIZED TO DERIVE THE NETWORK WHEN THE FOLLOW REGIME IS TURBULENT. THE EFFICIENCY AND THE RATE OF CONVERGENCE OF THE PROPOSED SUGGESTION CONCERNING INITIAL GUESS IS COMPARED AND CONTRASTED WITH CONVENTIONAL GUESSES PROPOSED IN THE CURRENT LITERATURE. RESULTS OBTAINED FROM THIS STUDY PROVIDED THE LEAST NUMBER OF ITERATIONS AND CPU TIME FOR SOME VERSION OF THE PROPOSAL COMPARED TO OTHER CONVENTIONAL GUESSES CITED IN THE LITERATURE. IN CONCLUSION, IT IS SUGGESTED THAT THE AVAILABLE COMMERCIAL AND PUBLIC DOMAIN SOFTWARE BE EQUIPPED WITH THIS PROPOSAL FOR ROUTINE APPLICATION.

IN THIS PAPER, A NEW NON-REFLECTING OPEN BOUNDARY CONDITION IS INTRODUCED IN ORDER TO SOLVE CIRCULAR CAVITY PROBLEMS. IN THIS REGARD, A NEW SEMI-ANALYTICAL METHOD IS USED TO DIAGONALIZE THE COEFFICIENT MATRICES OF GOVERNING DIFFERENTIAL EQUATION. THIS METHOD USES FOUR TOOLS IN ORDER TO DIAGONALIZE THE COEFFICIENT MATRICES IN WHICH THEY ARE: HIGHER-ORDER SUB-PARAMETRIC ELEMENTS, HIGHER-ORDER CHEBYSHEV MAPPING FUNCTIONS, WEIGHTED RESIDUAL METHOD AND CLENSHAW-CURTIS QUADRATURE. THIS METHOD IS DEVELOPED TO DIAGONALIZE THE DYNAMIC STIFFNESS MATRIX. TO THIS AIM, THE SUBSTRUCTURE METHOD IS USED. TWO FIRST ORDER ORDINARY DIFFERENTIAL EQUATIONS (I.E. INTERACTION FORCE-DISPLACEMENT RELATIONSHIP AND GOVERNING DIFFERENTIAL EQUATION IN DYNAMIC STIFFNESS) ARE SOLVED TO SATISFY THE RADIATION CONDITION AT INFINITY AND BOUNDARY CONDITION OF SOIL-STRUCTURE INTERFACE. THE INTERACTION FORCE-DISPLACEMENT RELATIONSHIP IS CONSIDERED AS A NONREFLECTING OPEN BOUNDARY CONDITION FOR THE BOUNDED MEDIUM SUBSTRUCTURE. TWO CAVITIES EMBEDDED IN A FULL-PLANE ARE CONSIDERED AS BENCHMARK EXAMPLES AND THE RESULTS ARE COMPARED WITH ANALYTICAL SOLUTIONS.

INCREMENTAL DYNAMIC ANALYSIS (IDA) PROCEDURE IS CURRENTLY CONSIDERED AS A STANDARD TOOL FOR ACCURATE ESTIMATION OF THE SEISMIC DEMAND AND CAPACITY OF STRUCTURES. THE METHOD REQUIRES SEVERAL NONLINEAR RESPONSE HISTORY ANALYSES (RHAS) OF THE STRUCTURE FOR A SET OF GROUND MOTIONS, EACH SCALED TO MULTIPLE LEVELS OF INTENSITY. RECOGNIZING THAT IDA IS EXTREMELY TIME-CONSUMING FOR PRACTICAL APPLICATIONS, SOME SIMPLIFIED PUSHOVER ANALYSIS-BASED METHODS HAVE RECENTLY BEEN DEVELOPED BY RESEARCHERS. THESE METHODS OFTEN COMBINE THE NONLINEAR DYNAMIC RESPONSE OF AN EQUIVALENT SINGLE-DEGREE-OF-FREEDOM (SDOF) SYSTEM WITH THE RESULTS OBTAINED FROM A STANDARD PUSHOVER ANALYSIS TO PROVIDE A RATHER CLOSED-FORM SOLUTION FOR THE COLLAPSE PROBLEM. THIS PAPER EXPLORES THE ACCURACY AND EFFECTIVENESS OF SOME APPROXIMATE PUSHOVER ANALYSIS-BASED METHODS (I.E., SPO2IDA, MPA-BASED IDA AND HAMIDIA ET AL. (2013) METHODS) IN ESTIMATING THE MEDIAN SIDESWAY COLLAPSE CAPACITY OF REGULAR RC MOMENT-RESISTING FRAMES. FOUR RC BUILDINGS WITH 3, 6, 9 AND 12 STORIES ARE DESIGNED AND SUBJECTED TO THE APPROXIMATE ANALYSIS METHODS. A DETAILED COMPARISON IS THEN PERFORMED BETWEEN THE RESULTS OBTAINED BY THE APPROXIMATE METHODS WITH THOSE GIVEN BY THE EXACT IDA APPROACH. FINALLY, IT IS REVEALED THAT ALL THE METHODS BASED ON EQUIVALENT SDOFS STUDIED IN THIS PAPER PROVIDE ACCEPTABLE COLLAPSE CAPACITY ESTIMATES OF THE FRAMES. HOWEVER, LESS ACCURATE PREDICTIONS ARE OBTAINED BY SPO2IDA AND MPA-BASED IDA METHODS FOR 16TH AND 84TH FRACTILE IDA CURVES IN ALL CASES. THE PAPER ALSO PRESENTS ADDITIONAL GUIDELINES TO IMPROVE THE MPA-BASED IDA METHOD IN ESTIMATING THE MEDIAN COLLAPSE CAPACITY OF INTERMEDIATE RC MOMENT-RESISTING FRAMES.

COLLAPSE PREVENTION OF STRUCTURES IS ONE OF THE MAIN AIM IN SEISMIC DESIGN CODE. THOUGH, EXPERIENCES EXHIBIT THAT MOST OF STRUCTURES IN SEVER EARTHQUAKES RECEIVE DAMAGES AND RESIDUAL DISPLACEMENTS. SUCH PERMANENT DISPLACEMENTS PREVENTS SERVICEABILITY AND IN SOME CASES IMPOSE REPAIR COSTS. ON THE OTHER HAND THE SEISMIC DESIGN OF SELF-CENTERING SYSTEM EXHIBITS EXCELLENT PERFORMANCE REGARDING THE ENERGY DISSIPATION, LOW DAMAGES AND MINIMIZING THE RESIDUAL DISPLACEMENTS. THE USE OF "HYBRID" PRECAST CONCRETE WALL STRUCTURES FOR HIGH SEISMIC REGIONS PROVIDES AMPLE ROCKING MODE OF BEHAVIOR AND REDUCES THE RESIDUAL TOP DISPLACEMENTS. THIS PAPER PRESENTS A THREE DIMENSIONAL NONLINEAR FINITE ELEMENT (FE) MODELS, USING ABAQUS TO PREDICT THE LATERAL FORCE-LATERAL DISPLACEMENT OF THE PRECAST CONCRETE SHEAR WALL SPECIMEN. THE NUMERICAL ANALYZED CARRIED OUT UNDER BOTH GRAVITY AND REVERSED-CYCLIC LATERAL LOADING TO INVESTIGATE THEIR SEISMIC NONLINEAR BEHAVIOR. THE OBTAINED RESULTS INDICATE THAT THE NONLINEAR NUMERICAL RESULTS OF TESTED SPECIMEN ARE MUTUALLY CORRELATE TO THE EXPERIMENTAL RESULTS.

IN THIS STUDY, EFFECT OF RECTANGULAR OPENING IN DIFFERENT SIZES AND VARIANT LOCATIONS ON CONCRETE SHEAR WALL DUCTILITY AND THEIR BASE SHEAR, MAXIMUM DISPLACEMENT AS WELL AS ENERGY DISSIPATION IN NEAR FAULT EARTHQUAKE IS INVESTIGATED. IN THIS INVESTIGATION THE MODEL OF CONCRETE SHEAR WALL IS PERFORMED USING ABAQUS FINITE ELEMENT SOFTWARE. THE RESULTS OF NUMERICAL STUDY ARE VALIDATED WITH RESULTS OF EXPERIMENTAL TEST. THERE IS A GOOD AGREEMENT BETWEEN RESULTS OF NUMERICAL MODEL AND EXPERIMENTAL TEST.THE OPENINGS HAVE AREA OF 0.1, 0.2, 0.25 AS WELL AS 0.3 SHEAR WALL AREA. THEY ARE ALSO LOCATED IN CENTER, UP AND RIGHT OF CONCRETE WALL AND UP AND RIGHT SIDE OF CONCRETE WALL. THE MODELS ARE SUBJECTED TO TWO NEAR FAULT EARTHQUAKE RECORDS. ENERGY ABSORPTION, BASE SHEAR AND MAXIMUM DISPLACEMENT OF MODELS ARE COMPARED. RESULTS INDICATED THAT OPENINGS DECREASE ENERGY ABSORPTION, BASE SHEAR AND LATERAL LOAD CARRYING CAPACITY. ALSO BEHAVIOR OF SHEAR WALL WAS SENSITIVE ABOUT LOCATION OF OPENING.

GEOCELL REINFORCED SOIL IS A CELLULAR MATTRESS WITH AN ALMOST HONEYCOMBED CONFIGURATION. THE GEOCELL REINFORCEMENT NOT ONLY INCREASE THE SOIL BEARING CAPACITY BUT ALSO REDUCE ITS SETTLEMENT. THERE IS LITTLE INFORMATION ON INTERACTION EFFECTS OF ITS GEOMETRY PARAMETERS. THIS PAPER DISCUSSES THE TRENDS OF FOOTING BEHAVIOR IN TERMS OF BEARING CAPACITY RATIO (BCR). SEVERAL DIFFERENT CONFIGURATIONS OF GEOCELL WERE EXAMINED. THE OBTAINED RESULTS SHOW A SLIGHT INTERACTION BETWEEN THE LENGTH OF THE GEOCELL LAYER AND THE REQUIRED COVER LAYER THICKNESS. THE MOST SIGNIFICANT PARAMETER IS FIND TO BE THE GEOCELL HEIGHT. ALTHOUGH THE OPTIMUM DIMENSION FOR THE HEIGHT, LENGTH AND APERTURE SIZE OF THE CELLS IS OBTAINED.

MODELING AND COMPUTER SIMULATION OF CONTAMINANT TRANSPORT HAS A LONG LASTING HISTORY IN GROUNDWATER HYDROLOGY. VARIOUS GEO-HYDROLOGISTS MADE AN EXTENSIVE EFFORT TO MODEL AND MIMIC THE DYNAMICS OF BOTH FLOW AND CONTAMINANT TRANSPORT IN POROUS MEDIA. HOWEVER, THE UNIQUE FEATURE OF SUCH EFFORTS IS THE LACK OF PROPER JUSTIFICATION CONCERNING THE MISMATCH OBTAINED VIA COMPARING OBSERVED AND SIMULATED BREAKTHROUGH CURVES. THE CURRENT STUDY IS CONDUCTED UNDER HIGHLY CONTROLLED EXPERIMENTAL SETUP IN UNIFORM SOIL TO ENHANCE AND BETTER EXPLAIN THE RATIONALITY BEHIND THE FAILURE EMERGING FROM REPRODUCTION OF BREAKTHROUGH CURVES BY ADVECTION-DISPERSION EQUATION (ADE) MODEL. AS THE BREAKTHROUGH CURVES OBTAINED FROM THE LABORATORY CANNOT BE DENIED, IT SEEMS SCIENTISTS SHOULD REVISE AND PERHAPS REVISIT THE ADE MODEL FOR A BETTER PERFORMANCE.

IN THIS STUDY, A NEW MODIFIED FIFTH-ORDER HARDY-CROSS METHODS IS PRESENTED FOR WATER DISTRIBUTION SYSTEMS. IN THE STEADY-STATE CONDITION, THE GOVERNING EQUATIONS OF WATER NETWORKS ARE THE CONTINUITY EQUATIONS FOR EACH NODE AND THE ENERGY EQUATIONS FOR EACH LOOP. THE FORMER EQUATIONS ARE LINEAR IN RESPECT TO FLOW RATE WHILE THE LATTER ARE NONLINEAR ALGEBRAIC ONES. THEREFORE, THE TRUE MEANING OF SOLVING A PIPE NETWORK IS TO SOLVE A SYSTEM OF NONLINEAR ALGEBRAIC EQUATIONS IN TERMS OF PIPE FLOW RATES. ON THE CONTRARY, THE HARDY-CROSS METHOD, AS ONE OF THE HYDRAULIC-SOLVER APPROACHES, SOLVES PIPE NETWORKS WITHOUT BUILDING THE AFOREMENTIONED SYSTEM OF EQUATIONS, WHICH IS SUPPOSED TO BE MORE EFFICIENT THAN THE MATRIX-BASED ONES. ALTHOUGH THE ORIGINAL HARDY-CROSS METHOD DOES NOT PROVIDE A MATRIX-BASED SCHEME, IT PERFORMS MUCH LESS EFFICIENT IN COMPARISON WITH THE OTHER MATRIX-BASED APPROACHES. THE HARDY-CROSS METHOD UTILIZES A SPECIFIC KIND OF INITIAL GUESS WHICH SATISFIES THE CONTINUITY EQUATIONS IN ADVANCE OF DEALING WITH THE ENERGY EQUATIONS, WHICH ARE INDIVIDUALLY SOLVED FOR EACH LOOP. HENCE, ONE OF THE MAJOR CHALLENGES OF THIS APPROACH IS ITS LOW RATE OF CONVERGENCE. THE PROPOSED MODIFIED HARDY-CROSS METHODS GRASP HIGHER ORDER OF CONVERGENCE THAN THE ORIGINAL APPROACH. FINALLY, THE COMPARISON OF THE PROPOSED FIFTH-ORDER HARDY-CROSS METHODS WITH THE ORIGINAL ONE CLEARLY DEMONSTRATES THAT THE RECOMMENDED MODIFICATION IMPROVES THE RATE OF CONVERGENCE OF THE ORIGINAL HARDY-CROSS METHOD.

THIS PAPER IS AIMED AT APPLYING INTEGRATION OF GEOSPATIAL INFORMATION SYSTEM (GIS) AND MULTI-CRITERIA DECISION MAKING (MCDM) METHODS AS A TOOL IN A MANNER IN WHICH IGNORING ENVIRONMENTAL, ECONOMIC, SCIENTIFIC AND ENGINEERING JUDGMENT IS AVOIDED. FIRSTLY, UTTERLY UNSUITABLE AREAS ARE EXCLUDED TO PROMOTE THE EFFICIENCY AND ACCURACY PRIOR TO APPLYING MCDM METHODS. SUBSEQUENTLY, THE REMAINING AREAS ARE NOT COMPLETELY UNSUITABLE, YET NOT THE MOST APPROPRIATE LOCATIONS FOR A LANDFILL. AFTERWARDS, POTENTIAL SITES ARE OBTAINED FROM MORE SUITABLE LOCATIONS. CONSIDERING TOO MANY CRITERIA IN THE FIRST STAGE COULD DECREASE THE EFFICIENCY OF THE ANALYTIC HIERARCHY PROCESS (AHP) METHOD; THEREFORE, TO DEPLOY A MORE PRAGMATIC APPROACH, A LIMITED NUMBER OF CRITERIA ARE CONSIDERED FOR INITIAL SELECTION OF CANDIDATE SITES. IN THE SECOND STAGE, POTENTIAL SITES ARE EVALUATED AND RANKED THROUGH A MORE THOROUGH INVESTIGATION UTILIZING THE ANALYTIC NETWORK PROCESS (ANP) METHOD. ADDITIONALLY, BUFFERS FOR UNSUITABLE ZONES OF LESS EMPHASIZED IMPORTANCE ARE ELIMINATED TOO, AND MORE CRITERIA ARE TAKEN INTO ACCOUNT.

THIS PAPER INVESTIGATES THE EFFECT OF VERTICAL COMPONENT OF EARTHQUAKES ON STABILITY OF SLOPES USING FE ANALYSIS. THE ANALYSES ARE CONDUCTED WITH THE IMPERIAL COLLEGE FINITE ELEMENT PROGRAM (ICFEP), USING THE MOHR-COULOMB FAILURE CRITERION, AND THE GENERALIZED-DECAY HYPERBOLIC MODEL ACCOUNTING FOR ELASTIC NONLINEARITY IN SMALL STRAIN RANGE. THE MODELS CONSIST OF SLOPES OF DIFFERENT GEOMETRY CONSTRUCTED ON DEEP SATURATED COHESIVE GRANULAR BEDROCK. THESE SLOPES ARE SUBJECTED TO MONOTONIC, HARMONIC, AND SEISMIC EXCITATIONS. THE RESPONSE OF MODELS TO THESE EXCITATIONS IS PRESENTED IN TERMS OF ACCUMULATED DEFORMATIONS, AND PLASTIC STRAINS. THESE RESULTS INDICATE THAT THE INCLUSION OF VERTICAL COMPONENT LEADS TO AN INCREASE IN PLASTIC DEFORMATION. THIS IS IN PARTICULAR MARKED FOR STEEP MODELS WHERE A COMPLETE SLOPE FAILURE DEVELOPS AS OPPOSED TO THE COMPARATIVELY GENTLE SLOPES WITH LOCALIZED PLASTIC ZONES. THE ANALYSES SUGGEST THAT IGNORING THE VERTICAL COMPONENT OF EARTHQUAKES IN SEISMIC STABILITY ANALYSIS CAN RESULT IN UNDERESTIMATION OF THE INDUCED DEFORMATIONS, AND CAN LEAD TO AN UNSAFE DESIGN. THIS CAN BE MORE SIGNIFICANT IN THE CASE OF STEEP SLOPES.

THE PURPOSE OF CONTROL STRUCTURE AGAINST EARTHQUAKE IS TO DISSIPATE EARTHQUAKE INPUT ENERGY TO THE STRUCTURE AND REDUCE THE PLASTIC DEFORMATION OF STRUCTURAL MEMBERS. THERE ARE DIFFERENT METHODS FOR CONTROL STRUCTURE AGAINST EARTHQUAKE TO REDUCE THE STRUCTURE RESPONSE THAT THEY ARE ACTIVE, SEMI-ACTIVE, INACTIVE AND HYBRID.IN THIS PAPER TWO DIFFERENT COMBINED CONTROL SYSTEMS ARE USED FIRST SYSTEM COMPRISES BASE ISOLATOR AND MULTI TUNED MASS DAMPERS (BI & MTMD) AND ANOTHER COMBINATION IS HYBRID BASE ISOLATOR AND MULTI TUNED MASS DAMPERS (HBI & MTMD) FOR CONTROLLING AN EIGHT STORY ISOLATED BENCHMARK STEEL STRUCTURE. ACTIVE CONTROL FORCE OF HYBRID ISOLATOR IS ESTIMATED BY FUZZY LOGIC ALGORITHMS. THE INFLUENCES OF THE COMBINED SYSTEMS ON THE RESPONSES OF THE BENCHMARK STRUCTURE UNDER THE TWO NEAR FIELD EARTHQUAKE (NEWHALL & ELCENTRO) ARE EVALUATED BY NONLINEAR DYNAMIC TIME HISTORY ANALYSIS.APPLICATIONS OF COMBINED CONTROL SYSTEMS CONSISTING OF PASSIVE OR ACTIVE SYSTEMS INSTALLED IN PARALLEL TO BASE-ISOLATION BEARINGS HAVE THE CAPABILITY OF REDUCING RESPONSE QUANTITIES OF BASE-ISOLATED (RELATIVE AND ABSOLUTE DISPLACEMENT) STRUCTURES SIGNIFICANTLY. THEREFORE IN DESIGN AND CONTROL OF IRREGULAR ISOLATED STRUCTURES USING THE PROPOSED CONTROL SYSTEMS, STRUCTURAL DEMANDS (RELATIVE AND ABSOLUTE DISPLACEMENT AND ECT) IN EACH DIRECTION MUST BE CONSIDERED SEPARATELY.

IN THIS RESEARCH, BASED ON THE CONCEPT OF ISOGEOMETRIC ANALYSIS, AN ALGORITHM IS DEVELOPED FOR SOLVING SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS. IN ISOGEOMETRIC ANALYSIS METHOD, SOLUTION OF DIFFERENTIAL EQUATIONS ARE CONSIDERED AS IMAGINARY CURVES OR SURFACES WHICH ARE CONSTRUCTED BY USING ADVANCED VERSIONS OF SPLINES SUCH AS NON-UNIFORM RATIONAL B-SPLINES (NURBS). IN THE SAME MANNER, COEFFICIENTS OF DIFFERENTIAL EQUATIONS, WHICH THEMSELVES MIGHT BE FUNCTIONS IN GENERAL, CAN BE ASSUMED AS OTHER IMAGINARY CURVES OR SURFACES. AN IGA FRAMEWORK IS CREATED IN MATLAB TO SOLVE PROBLEMS. THE ANALYSIS RESULT IS COMPARED WITH EXACT AND OTHER METHODS SOLUTIONS. FINALLY, THE EFFECT OF DIFFERENT PARAMETERS ON THE SOLUTION OF AN EXAMPLE IS INVESTIGATED.

CURRENT RESEARCH IS CARRIED OUT ON OUTRIGGER BRACED STEEL STRUCTURES WITH WELDED CONNECTIONS, ILLUSTRATING THE EFFECT OF USING SEISMIC BASE ISOLATION SYSTEM UNDER THE TOP STORIES, ON THE SEISMIC BASE SHEAR FORCES OF ABOVE MENTIONED STRUCTURES. FOR THIS PURPOSE, 8 TWO DIMENSIONAL 20~60 STORIES HIGH OUTRIGGER BRACED STRUCTURES ARE MODELED AND DESIGNED ACCORDING TO THE IRANIAN 2800 SEISMIC CODE, DUE TO 1ST, 2ND AND 3RD TYPES OF SOIL SPECIFICATIONS AND SA=0.25G & SA=0.35G SPECTRAL ACCELERATIONS. ON THE NEXT STAGE, ALL DESIGNED MODELS ARE EQUIPPED WITH BASE ISOLATION SYSTEM UNDER THE TOP ONE OR TWO STORIES (BASED ON THE HEIGHT OF THE STRUCTURE), TO PERFORM AS A SOFT STORY ON THE TOP OF THE WHOLE STRUCTURE, DEMONSTRATING A TUNED MASS DAMPER PASSIVE CONTROL SYSTEM (TMD) THERE. AFTER TUNING THE FREQUENCY AND THE DAMPING RATIO FOR THIS SECONDARY SYSTEMS, TIME HISTORY ANALYSIS IS CARRIED OUT FOR ALL PRELIMINARY AND SECONDARY SYSTEMS DUE TO ACCELEROGRAMS RECORDED ON ABOVE MENTIONED SITE SPECIFICATIONS, NORMALIZED TO SA=0.25G & SA=0.35G. FINALLY, BY STUDYING THE LATERAL BASE SHEAR FORCE OF ALL PRELIMINARY AND SECONDARY MODELS FOR ALL MENTIONED RECORDS, THE EFFECTS OF USING BASE ISOLATION SYSTEM ON THE TOP OF OUTRIGGER BRACED STRUCTURES ARE DISCUSSED.

DYNAMIC INTERACTION OF FOUNDATIONS WITH THE UNDERLYING SOIL MEDIUM IS ONE OF THE IMPORTANT FACTORS THAT SHOULD BE CONSIDERED WHEN DESIGNING A STRUCTURE’S FOUNDATION. IN THIS STUDY, HARMONIC RESPONSE OF A FLEXIBLE CIRCULAR FOUNDATION WHICH IS BONDED TO THE SURFACE OF A TRANSVERSELY ISOTROPIC HALF-SPACE IS INVESTIGATED IN DETAIL. TO ACHIEVE THIS END, FIRST A 3D FINITE ELEMENT PROGRAM HAS BEEN DEVELOPED, WHICH IS CAPABLE OF HANDLING PROBLEMS IN ELASTICITY IN FREQUENCY DOMAIN. NEXT, THE FUNDAMENTAL SOLUTIONS OF THE HALF-SPACE HAVE BEEN UTILIZED IN ORDER TO PREPARE A BOUNDARY ELEMENT CODE THAT HAS THE ABILITY TO SOLVE TRACTION/DISPLACEMENT BOUNDARY VALUE PROBLEMS OF TRANSVERSELY ISOTROPIC HALF-SPACES. FINALLY, WE USE THE STIFFNESS, MASS AND INFLUENCE COEFFICIENT MATRICES IN A DIRECT FEM/BEM COUPLING SCHEME TO OBTAIN THE FOUNDATION RESPONSE. THE PROGRAMS FOR THIS STUDY HAVE BEEN ALL WRITTEN IN MATLAB. AT THE END, THE RESULTS ARE VERIFIED FOR THE CASE OF A RIGID FOUNDATION LOCATED ON AN ISOTROPIC HALF-SPACE. MOREOVER, SEVERAL GRAPHS ARE PRESENTED FOR DIFFERENT VALUES OF FOUNDATION FLEXIBILITY. THE EFFECT OF THE DEGREE OF ANISOTROPY OF TRANSVERSE ISOTROPIC HALF-SPACE ON THE FOUNDATION RESPONSE WAS ALSO INVESTIGATED. THESE RESULTS CAN BE USED IN DESIGN OF SUCH FOUNDATIONS.

BIOLOGICAL SOIL STABILIZATION IS A NEW AND ENVIRONMENT FRIENDLY METHOD OF SOIL IMPROVEMENT. IN THIS METHOD THE UREASE ACTIVITY OF A BACTERIA CAUSE THE PRECIPITATION OF THE CALCIUM CARBONATE IN THE SOIL MEDIUM. THIS METHOD HAS BEEN PERFORMED BY INJECTION OF SOLUTIONS TO THE SOIL WHICH ARE CONTAINED THE NEEDED MATERIALS FOR INITIATING THE PROCESS. BESIDES THE SOIL PROPERTIES SUCH AS SOIL GRADING, POROSITY, ETC., THE CEMENTATION SOLUTION PROPERTIES AFFECTS THE OBTAINED RESULTS OF THIS METHOD. THE LATTER PROPERTIES INCLUDE INJECTION METHOD, SOLUTION CONCENTRATION AND PH. AS A RESULT, THIS PROCESS CAUSES THE BOUNDING OF THE SOIL GRAINS. ANOTHER IMPORTANT RESULT OF THE MENTIONED METHOD IS DECREASING THE PERMEABILITY OF THE SOIL. IN THE PRESENT PAPER, AN ENGINEERING LANDFILL LINER IS MODELED BY SEEP/W SOFTWARE TO EVALUATE THE EFFECT OF THE BIOLOGICAL SOIL IMPROVEMENT METHOD ON CONTROLLING THE LEAKAGE OF THE WASTE LIQUIDS AROUND THESE LANDFILLS.