کنفرانس بین المللی سواحل، بنادر و سازه های دریایی
سال:1368 | دوره:1 |تعداد مقالات:11

IN ORDER TO CONNECT THE LAND AND THE SEA FOR CARGO AND PASSENGER TRANSPORTATION, IT IS NECESSARY TO CONSTRUCT TERMINALS IN SUITABLE DISTANCES OF THE COAST. THE EXISTENCE OF SEA TIDES AND ACCESS TO AN ADEQUATE WATER DEPTH FOR THE SHIPS TO BERTH ON THE ONE HAND SEEMS NECESSARY FOR TERMINALS TO BE CONNECTED TO THE LAND, AND ON THE OTHER, THEY SHOULD BE FLOATING TO MOVE UP OR DOWN USING THE JACK-UP SYSTEMS. THE FLOATING SYSTEM IS PREFERRED TO THE JACK-UP SYSTEM DUE TO ITS SIMPLICITY AND THE OBTAINED EXPERIENCE. MOREOVER, THE CURRENT SYSTEM IS USED IN OFFSHORE STRUCTURES BECAUSE OF ITS PARTICULAR FEATURES. THE STRUCTURE USED FOR THIS PURPOSE IS T-SHAPED, WHICH IS FULLY BOLSTERED ON SPANS AND HAS RESILIENT BOLSTER ON ITS FLOATING SIDE. THE SURFACE IS MADE OF METAL SHEETS AND ITS INTERIOR ELEMENTS ARE OF TRUSS (DUAL-FORCE) PARTS, WHICH ARE CONNECTED TO EACH OTHER IN A PYRAMID STYLE, IN ORDER TO FACILITATE MOORING AND SHIP OPERATIONS. IN ADDITION TO THE LATERAL LOADS SUCH AS WAVES, WIND, CURRENT, THE FORCES OF MOORING AND PIERS, THIS STRUCTURE BEARS THE DYNAMIC LOADS OF THE VEHICLES SUCH AS TRAILERS, TRUCKS, TANKS AND PORTABLE CRANES. IN ORDER TO MAKE THE STRUCTURE BULLETPROOF AND PREVENTING IT FROM SINKING, FOAM IS INJECTED INTO THE FLOATING PART OF THE STRUCTURES. AN ANCHORAGE IS DESIGNED NEAR THE BERTHS FOR THE USE OF MOORING SHIPS. THE STRUCTURE IS DIGITALLY ANALYZED AND PRESENTED IN A 3D MODEL.

TODAY, THE GRAINY BREAKWATERS ARE FINANCIALLY AND TECHNICALLY IMPORTANT IN BERTH CONSTRUCTION. THE ADVANTAGE OF THESE BREAKWATERS IS GENERALLY IN ITS SIGNIFICANT FLEXIBILITY, LOW MAINTENANCE AND UTILIZATION ISSUES AND FINALLY THEIR EASE OF CONSTRUCTION. ALTHOUGH THEIR STRENGTH IS MOSTLY IMPUTED TO ITS ARMOR AND LOWER LAYERS, REGARDING THE GEOTECHNICAL AND HYDRAULICS SCIENTIFIC AND TECHNOLOGICAL ADVANCES OF THE LAST TWO DECADES HAS INDICATED THE LONG-TERM EFFECTS OF CORE MATERIALS AND ITS HYDRAULIC-STRUCTURAL PERFORMANCE. THE NECESSITY FOR KNOWING MOST OF BREAKWATERS BEHAVIOR HAS BEEN GENERALLY ACCEPTED BY MANY EXPERTS AFTER MANY INCIDENTS AND DAMAGES HAD HAPPENED FOR LARGE BREAKWATERS AT THE ATLANTIC OCEAN AND THE MEDITERRANEAN SEA (E.G. THE SINES PORT OF PORTUGAL, TRIPOLI PORT OF LIBYA, GIOLA TAURO PORT OF ITALY, SKIKDA, VARVAN AND AREZU PORTS OF ALJAZEERA AND ETC). THE ARMOR LAYER PLAYS THE ROLE OF ENERGY DEPRECIATION CAUSED BY WAVES AND THE ROLE OF WAVE REFLECTION OR RESONANCE AND THEY PROTECT THE BREAKWATER'S BODY AND INCREASE THE USEFUL LIFETIME OF THESE STRUCTURES. VARIOUS INVESTIGATIONS HAVE INDICATED THAT THE STRENGTH OF STONE LAYERS IN THE ARMOR LAYER DEPENDS ON THE FOLLOWING PARAMETERS: WAVES HEIGHT, SPEED, RESONANCE AND GROUPING WHICH INCLUDES FORCES OF LIFTING, INERTIA AND DRAGGING; THE WEIGHT OF STONY BLOCKS AND THE SUBMERGED WEIGHT (THE DENSITY OF THE SOLID AND THE ADJACENT LIQUID); ARRANGEMENT, INTERLOCK, INFRACTION FORCE AND THE INTERNAL INFRACTION ANGLE BETWEEN BLOCKS; THE CORE'S PERMEABILITY LEVEL; AND THE CONDITION OF THE ARMOR LAYER BASE (THE LINING LAYER'S CONDITION).

THE FLOATING PIPELINES IN WATER ARE VASTLY USED IN THE TRANSFERRING OF INDUSTRIAL WASTE, WATER AND OTHER FLUIDS SUCH AS OIL AND ITS PRODUCTS, AND SUPPLYING WATER TO THE COOLING TOWERS AND ALSO AS UNDERWATER TUNNELS. REGARDING THE COMPLEXITY OF THE FORCES IMPOSED ON SUCH STRUCTURES AND THE VARIETY OF SHAPE AND CHARACTERISTICS OF WAVES, ANALYSIS AND DESIGN OF THESE STRUCTURES ARE FACING DIFFERENT ISSUES, WHICH INDICATE THE NEED OF A MULTILATERAL INVESTIGATION OF THE INERTIA AND THE PIPELINE STRUCTURES IN THE HYDRODYNAMIC POINT OF VIEW. SINCE THIS ISSUE IS MOST APPLICABLE IN THE PETROLEUM PORTS OF OUR COUNTRY FOR OIL AND OTHER PETROLEUM PRODUCTION TRANSPORTATION TO THE PETROLEUM TERMINALS, THE IMPORTANCE OF ANALYZING THESE STRUCTURES BECOMES MORE AND MORE OBVIOUS. GENERALLY SPEAKING, THE INTERACTION OF SEA WAVES AND THE PIPELINE STRUCTURES INCREASES THE DYNAMIC SHOCKS OF THE PIPELINES. THUS, IT IS NECESSARY TO USE AND ANALYZE A SUITABLE MODEL FOR CONTROLLING THESE SHOCKS. IN THIS ARTICLE, BY EXPLAINING ALL OUTSIDE, INSIDE AND HYDRODYNAMIC FORCES AND THE OPERATION PROCESS OF EACH OF THESE FORCES, THE EFFECTIVE EQUATIONS OF THE FLOATING PIPELINES ARE DETERMINED.

AT THE REGION OF CHABAHAR, CONSTRUCTING VARIOUS BERTHS ARE CONSIDERED OR ARE BEING CONSTRUCTED, IN ORDER TO PROTECT WHICH, SOME BREAKWATERS ARE CONSIDERED FOR THIS PURPOSE. THESE BREAKWATERS, WHILE HAVING THE SEMI-SIMILAR GENERAL CONDITIONS, ALL HAVE THEIR OWN PARTICULAR BASE SHAPE, SO IN THIS ARTICLE, IT IS TRIED TO DESCRIBE THE GENERAL CONDITIONS AND THE EFFECTIVE FACTORS IN THEIR DIFFERENCE OR SOMEHOW THEIR SEMI-SIMILAR LOOKS ARE SURVEYED. FOR THIS PURPOSE, FIRST THE GENERAL INFORMATION NEEDED FOR BREAKWATER DESIGN WHICH ARE COMMON IN THIS AREA ARE EXPLAINED AND AFTER THAT, THERE IS A BRIEF DESCRIPTION OF EACH BERTH. WHILE DOING THE MENTIONED DESCRIPTION, THE PLAN AND THE SECTION OF THE BREAKWATERS END OF EACH BERTH ARE POINTED OUT AND THE PLAN AND THE OTHER ADDITIONAL SECTION INDICATING THE INITIAL BREAKWATER DESIGNS ARE APPENDED. FINALLY, BY ELABORATING ON THE CHARACTERISTICS AND THE INFORMATION OF THE SECTION TYPE OF EACH BREAKWATER IN A TABLE, A GENERAL COMPARISON BETWEEN THE LOCAL PROJECTS IS PERFORMED AND THE RELATIVE RESULTS ARE PRESENTED.

SINCE DESIGNING BOTH INSIDE AND OUTSIDE WATER MARITIME STRUCTURES ARE DEALING WITH MANY PARAMETERS AND SELECTING SUCH STRUCTURES ARE FINANCIALLY SIGNIFICANT, DETERMINING THE SELECTION PARAMETERS OF THESE STRUCTURES SEEMS NECESSARY. IN THIS REGARD, IN THIS ARTICLE AFTER AN INTRODUCTION RELATED TO THE SELECTION PARAMETERS OF MARITIME STRUCTURES, THE RELATIVE STUDIES WHICH SHOULD BE DONE BEFORE SELECTING THE LOCATION ARE CATEGORIZED AND PRESENTED. CONSIDERING THE FACT THAT IN THE DESIGN OF MANY BERTHS AND PIERS AND OTHER MARITIME STRUCTURES OF OUR COUNTRY, WE GENERALLY FACE THE ISSUE OF LOCATION SELECTION, IT IS HOPED THAT THIS ARTICLE CAN TAKE A SMALL STEP IN SOLVING THIS ISSUE.

IRAN BANDAR, LOCATED AT THE SOUTHWEST CORNER OF POZM PLATEAU ON THE WESTERN SIDE OF THE GULF OF CHABAHAR WAS CONSTRUCTED IN 1978 BY BROWN ANDREW COMPANY AS A LOGISTIC BERTH LOCATION FOR IMPORTING THE EQUIPMENT OF THE LARGE MILITARY BERTH OF CHABAHAR. IN THE PRIMARY BERTH MODEL FOR MORE PROPERTY PRESERVATION IN THE FOUR-MONTH PERIOD OF MONSOONS, A 50-METER LONG BREAKWATER WAS CONSIDERED. AFTER THE ISLAMIC REVOLUTION, SINCE THE APPLICATION OF THE PORT HAD CHANGED AND THE LOGISTIC BERTH WAS TURNED INTO A COMMERCIAL – MILITARY BERTH, THE MODEL WAS BASICALLY CHANGED AND THE NECESSITY OF THE LONG BREAKWATER WAS IDENTIFIED. IN THIS REGARD, SOME RECOMMENDATIONS WERE PROVIDER FROM THE PROJECT'S EMPLOYER AND CONSULTANT, AND BECAUSE OF THE SIGNIFICANCE OF THIS PROJECT, IT WAS GIVEN TO THE DENMARK HYDRAULICS INSTITUTE. THIS INSTITUTE, WITH ITS PROFILE IN STUDIES OF THIS FIELD, HAS CONTROLLED THE WAVES OF THE PROPOSED AREA BY A MATHEMATICAL MODELING, WHILE IT HAS HYDRAULICALLY CONSTRUCTED THE MODEL AND SIMULTANEOUSLY TESTED THE BREAKWATER'S SECTION. AFTER CONSULTING THE EMPLOYER, THE LENGTH, DIRECTION AND THE CHARACTERISTICS OF THE BREAKWATER'S SECTION WERE DETERMINED (IN DIFFERENT LOCATIONS). THE PROPOSED MODEL WAS REVIEWED IN AN APPLICATORY POINT OF VIEW, AND BY CONSIDERING THE CHARACTERISTICS AND THE CONDITIONS OF LOCAL ROCKS AND BY THE EXPERIENCES OF USING DIFFERENT ROCKS IN OTHER CONSTRUCTED BREAKWATERS OF THE AREA. CONSIDERING THE EXISTING PIER'S CONDITION AND THE CONDITION OF THE PREVIOUSLY DREDGED CANAL, THE MODEL CHANGED SO THAT WHILE PROVIDING THE ESSENTIAL PRESERVATION, THE LENGTH CAN ALSO BE INCREASED.

DURING THE YEARS I SERVED AS THE SENIOR CAPTAIN AND THE MANAGER OF TOWING OPERATIONS OF THE NATIONAL OIL COMPANY, I FACED MANY ISSUES RELATED TO REPAIRING AND MAINTAINING THE OPERATIVE BERTHS AND VESSELS. THESE ISSUES RESULTED IN A VAST STUDY AND RESEARCH ON THE CAUSATIVE FACTORS OF METAL CORROSION AND THE WAYS OF PREVENTING IT AND THE ACCURATE AND NORMATIVE WAYS OF RUST REMOVAL AND PREPARATION OF SURFACES FOR PAINTING. IF THE CORROSIVE FACTORS ARE REMOVED IN TIME AND WITH PRINCIPLE OR WHILE PREPARING THE SURFACES AND USING COATING PAINT SYSTEMS THE NECESSARY INSTRUCTIONS AND ESSENTIAL POINTS ARE HEEDED, THE POSSIBLE DAMAGE WILL BE PREVENTED IN A FAVORABLE WAY.

BREAKWATERS ARE STRUCTURES WHICH PROTECT THE BERTHS AGAINST THE DESTRUCTIVE EFFECTS OF SEA WAVES. THE ORIGIN OF BREAKWATER STRUCTURES GOES BACK TO 4,000 TO 5,000 YEARS AGO, AND PHOENICIANS WERE THE FIRST TO BUILD THE INITIAL BREAKWATERS. IN THE 19TH CENTURY AND IN EARLY 20TH CENTURY, SIMILAR BREAKWATERS WERE CONSTRUCTED, WHICH WERE NOT SATISFACTORY BECAUSE OF THE DAMAGE AND THE INCIDENTS THEY CAUSED. TWO BREAKWATERS OF ALGIERS AND CATANIA ARE FROM THIS CATEGORY, AND BOTH WERE UTTERLY DESTROYED BECAUSE OF THE SLIDING OF THEIR ROCKS ON EACH OTHER. AS A RESULT AND IN ORDER TO PREVENT SUCH DAMAGES, IT SEEMED NECESSARY TO PERFORM INVESTIGATIONS IN THIS FIELD. GENERALLY SPEAKING, BREAKWATERS ARE DIVIDED INTO TWO GROUPS IN TERMS OF CONSTRUCTION AND DESIGN. THE FIRST CATEGORY IS THE RUBBLE MOUND BREAKWATERS, WHICH ARE THE OLDEST BREAKWATERS AND THE SECOND CATEGORY IS THE VERTICAL WALL BREAKWATERS, WHOSE CONSTRUCTION AND DESIGN IS INDEBTED TO THE ADVANCES OF STRUCTURE ENGINEERING SCIENCE AND TECHNOLOGY IN THE CURRENT ERA. THIS PAPER SERVES TO REVIEW THE DIFFERENT CHARACTERISTICS OF THE TWO TYPES, AND DELVES INTO THE MATHEMATICAL DETAILS REGARDING THEIR DESIGN AND CONSTRUCTION.

IN THIS ARTICLE, NEW AND CREATIVE METHODS FOR SOLVING THE ISSUE OF A PERMANENT BRIDGE OVER THE LAKE OF URMIA, WHICH ARE MOSTLY RELATED TO THE BASE OR THE FOUNDATION OF THIS BRIDGE ARE INTRODUCED, AND IT BECOMES OBVIOUS THAT THE RESULTS CAN BE USED IN FURTHER RESEARCHES SUCH AS BRIDGING, BERTH CONSTRUCTION AND SO ON, WHICH HAVE SIMILAR CONDITIONS.

THE STRUCTURE ANALYSIS SOFTWARE HAS ADVANCED VASTLY IN RECENT YEARS. IN THIS REGARD, THE ISSUES RELATED TO THE GEOMETRICAL MODELING OF COMPLICATED STRUCTURES, WHICH OCCURRED IN THE LAST 10 OR 15 YEARS, HAVE BEEN PRACTICALLY VANISHED AND INSTEAD THE CALCULATOR ENGINEERS ARE CONTEMPLATING IN ACCURATELY DETERMINING THE BEHAVIORAL MODEL OF THE STRUCTURES. THIS ARTICLE FOCUSES ON THE ANALYSIS AND PROPOSING THE IMPROVEMENT PROJECT AND REINFORCING ONE OF THE BERTHS OF THE PORTS AND MARITIME ORGANIZATION, WHICH HAS LOST THE TRANSPORTABILITY AND BERTHING ABILITY OF ITS INITIAL DESIGN BECAUSE OF AN ACCIDENT AND RESTORING ITS INITIAL CAPACITY IS OF GREAT IMPORTANCE.

THE TIDAL AREAS IN MARITIME STRUCTURES ARE UNDOUBTEDLY ONE OF THE MOST VULNERABLE PARTS OF THESE STRUCTURES. CONTINUOUS AND SEVERE WAVE IMPACTS, LARGE AMOUNT OF OXYGEN, LACK OF CATHODE PROTECTION, SALT SPRAY CONSTANTLY GETTING DRY AND WET ON THIS SURFACE ARE TWO OF THE ACCESSING ISSUES OF THIS PART WHICH ALL ARE STRESSING THE IMPORTANCE OF THE PRESERVATION OF THE MARITIME STRUCTURES TIDAL AREAS. THE CATHODE PROTECTION SYSTEM CANNOT BE HELD IN THIS AREA BECAUSE OF THE PRESENCE OF A CONSTANT ELECTROLYTE. ON THE OTHER HAND, THE MODERN INDUSTRIAL PAINTS SHOULD BE PAINTED ON DEVICES INSIDE WORKSHOPS AND WITH COMPLICATED PROCEDURES, SO THAT THE MAXIMUM COVERING STRENGTH IS OBTAINED. THUS, THE IMPLEMENTATION OF SUCH COATINGS FOR MARITIME FACILITIES ESPECIALLY IN HARSH ATMOSPHERIC CONDITIONS OF THE TIDAL AREAS IS TOO DIFFICULT AND DOES NOT RESULT IN THE DESIRED EFFICIENCY. IN THIS ARTICLE, A SURVEY IS PERFORMED ON THE AMOUNT OF CORROSION AND HOW IT IS CREATED IN THIS AREA OF THE MARITIME STRUCTURES, AND ALSO THE CORROSION PREVENTION METHODS INCLUDING METAL AND NON-METAL COATINGS ARE EXPRESSED. MOREOVER, THE EXPERIENCES OF THE IRANIAN OFFSHORE OIL COMPANY IN RELATION TO THIS TOPIC AND COMPARING IT TO THE EXISTING CONSERVATION METHODS ARE DISCUSSED.