ABUJA, NIGERIA
STRUCTURAL OPTION
TOBI JEWOOLA
SYNTRA TOWERS
BUILDING STATISTCS
BUILDING NAME SYNTRA TOWERS
LOCATION ABUJA, NIGERIA
OCCUPANCY TYPE MIXED USE OFFICE AND RESIDENTIAL BUILDING
SIZE 127,000 SF
NUMBER OF STORIES 11 STORIES ABOVE GRADE
DATE OF CONSTRUCTION NOVEMBER, 2013 TO DECEMBER, 2016
ESTIMATED COST INFO. $22 MILLION
PROJECT TEAM
ARCHITECT PROACTIVE DESIGN AND BUILDING SYSTEMS
STRUCTURAL ENGINEER ETTEH ARO AND PARTNERS
MEP ENGINEER ABBOT ENGIEERING CO. LTD. BUILDING SERVICES
CONTRACTOR JULIUS BERGER NIGERIA PLC.
ARCHITECTURE
SYNTRA TOWERS WAS DESIGNED TO EXHIBIT A BEAUTIFUL MERGER BETWEEN CONCRETE (WHICH IS VERY EVIDENT IN NIGERIAN BUILDINGS) AND CURTAIN WALLS. ITS PROFILE IMITATES THE LOOK OF A LIGHT FRAME STRUCTURE SITTING ON TOP OF A MASSIVE CONCRETE BASE. THE 11- STORY SUPERSTRCUTURE WILL INCORPORATE A MIXTURE OF 27 APARTMENT UNITS, A PENTHOUSE WITH A MINI OFFICE SPACE (FOR THE OWNER) AND A BANKING HALL. THERE WILL ALSO BE UNDERGROUNG PARKING GARAGES OCCUPYING TWO LEVELS BELOW GRADE. THE BUILDING IS OWNED BY AN EX-PRESIDENT OF A MAJOR NIGERIAN POLITICAL PARTY. AS A RESULT, THE APARTMENTS WILL ONLY BE LEASED TO TRUSTED AND KNOWN ASSOCIATES OF THE OWNER. HOWEVER, THE BANKING HALL WILL BE OPENED TO THE PUBLIC.
ZONING RESTRICTIONS
THIS BUILDING WAS CONSTRUCTED IN ABUJA, NIGERIA. AS A RESULT, ZONING REQUREMENTS FOR THE SITE WERE NOT SPECIFIED. THERE ARE NO HIGHLIGHTED RESTRICTION FOR THE SITE. FUTHER INVESTIGATION ON THIS TOPIC IS BEING INVESTIGATED AT THE MOMENT.
CODES
NATIONAL BUILDING CODE OF NIGERIA 2006
THE CODE GOVERNS ALL ENGINEERING SYSTEMS. THERE WERE DESIGN GUIDES USED IN THE DESIGN OF THE DIFFERENT ENGINEERING SYSTEMS OF THE BUILDING. HOWEVER, THE NATIONAL BUILDING CODE OF NIGERIA SERVED AS THE ULTIMATE DESIGN GUIDE FOR ALL SYSTEMS.
SUSTAINABLE FEATURES
SINCE SYNTRA TOWERS WAS DESIGNED FOR AND CONSTRUCTED ON A SITE OUTSIDE OF THE UNITED STATES, LEED CERTIFICATION WAS NOT PURSUID IN THE DESIGN. HOWEVER, EVIDENCE OF ENERGY SAVING MEASURES SUCH AS PROPER INSULATION OF BUILDING MATERIALS (ESPECIALLY WALLS), ARE SEEN THROUGHOUT THE BUILDING.
BUILDING ENCLOSURE
SYNTRA TOWERS WILL BE ENCLOED WITH METAL WALL PANELS, CONCRETE WALLS AND CURTAIN WALLS. AS SEEN IN FIGURE 3 ON THE LEFT, THE CURTAIN WALLS ARE SITUATED AT DIFDERENT LOCATIONS ON THE FACADE. LIKEWISE, THE CONCRETE WALLS (IN GRAY) ARE VISIBLE AT MULTIPLE LOCATIONS ON THE FACADE. THE METAL WALL PANELS (IN GREEN) ON THE OTHER HAND, ARE MORE UTILIZED ON THE UPPER FLOORS AS SEEN IN FIGURE 3.
ROOFING MATERIAL USED IN SYNTRA TOWERS CONSISTS MAINLY OF 4 LAYERS OF BITUMINOUS FELT. OTHER MATERIAL USED IN FACILITATING ROOF DRAINAGE AND WATERPROOFING INCLUDE FLASHING, FIBER CANT AND COUNTER FLASHING. THESE ROOF MATERIALS ARE ALL SUPPORTED ON A REINFORCED CONCRETE SLAB. THE ROOFING AT SYNTRA TOWERS IS GRAPHICALLY ILLUSTRATED IN FIGURE 5 WHILE TYPICAL EXTERIOR WALLS ARE ILLUSTRATE IN FIGURE 4.
Image Courtesy of Proactive Design and Building Systems
Figure Courtesy of Proactive Design and Building Systems
Image Courtesy of Proactive Design and Building Systems
Figure 2: Site Plan of Sytra Towers
Figure 3: An aeiral view showing the metal wall panels (in green) and the concrete walls (in gray) enclosing Syntra Towers
Figures Courtesy of Proactive Design and Building Systems
Figure Courtesy of Proactive Design and Building Systems
STRUCTURAL SYSTEM
THE STRUCTURAL SYSTEM IN SYNTRA TOWERS COMPRISES MAINLY OF CONCRETE MEMBERS. A TYPICAL BAY IN THE BUILDING IS A RECTANGULAR BAY OF DIMENSION 17.5 FT. BY 23.7 FT., WHICH VARIES TOWARDS THE CURVED EDGES, STAIRWELLS AND ELEVATOR CORES. THE FLOORS AND ROOF ARE SUPPORTED BY 8 IN THICK REINFORCED CONCRETE TWO WAY SLABS WITH BEAMS. THE SLABS, IN CONJUCTION WITH THE REINFORCED CONCRETE BEAMS, FRAME INTO THE REINFORCED CONCRETE COLUMNS WHICH IN TURN, TRANSFER THE ENTIRE GRAVITY LOAD OF THE BUILDING TO THE GROUND, WHERE THEY SIT ON A 3 FT. MAT FOUNDATION.
THE LATERAL SYSTEM COMPRISES OF REINFORCED CONCRETE SHEAR WALLS. LIKE THE GRAVITY SYSTEM, THE WALLS ARE ALSO SUPPORTED ON THE 3 FT. REINFORCED MAT FOUNDATION.
IN ADDITION TO THE GRAVITY AND LATERAL SYSTEMS MENTIONED, THE SUBSTRUCTURE HOUSES A 12 FT. WIDE REINFORCED CONCRETE RAMP. THE RAMP SUPPORTS VEHICLES MOVING FROM LEVEL TO LEVEL, (PARKING GARAGE 1 AND 2), IN AND OUT OF THE PARKING GARAGES.
LIGHTING AND ELECTRICAL SYSTEM
8 IN. 100 WATT INCANDESCENT LAMPS ARE THE PRIMARY FIXTURES USED IN THE RESIDENTIAL APARTMENTS AND THE GYM. 2 X 4 LUMINARES WITH T12 LAMPS ARE USED PRIMARILY IN THE BANKING HALL, RETAIL SPACES AND OFFICES.
IN SYNTRA TOWERS, UNAVAILABILITY OF 24-7 POWER SUPPLY IS HIGHLY EXPECTED AS THIS IS A RE-OCCURING SITUATION WITH POWER SUPPLY IN NIGERIA. AS A RESULT, THREE BACK UP GENERATORS, 400 kW EACH, ARE INSTALLED IN THE POWERHOUSE ADJACENT TO THE MAIN BUILDING WITH THE INTENT OF SUPPLYING POWER TO THE ENTIRE BUILDING DURING POWER OUTAGES.
MECHANICAL SYSTEM
NIGERIA EXPERIENCES A LOT OF HEAT. THERE ARE HARDLY ANY COLD SEASONS. THEREFORE, COLLING LOADS ARE HIGHLY CONSIDERED (BASICALLY THE ONLY CONSIDERATION) IN THE DESIGN OF THE HVAC SYSTEMS AT SYNTRA TOWERS. TO SUPPLY AIR CONDITIONING TO THE BUILDING, 12 AIR HANDLING UNITS LOCATED AT THE TOP OF THE ROOF ARE USED.
ALSO, A COOLING TOWER, LOCATED AT THE POWERHOUSE, WORKS IN CONJUCTION WITH THE AIR HANDLING UNITS IN COOLING HOT WATER AND SUPPLYING COOL AIR TO THE BUILDING.
CONSTRUCTION
CONSTRUCTION OF SYNTRA TOWERS BEGAN IN JANUARY 2014.THE BUILDING IS SCHEDULED TO BE COMPLETED IN DECEMBER OF 2016. JULIUS BERGER, THE GENERAL CONTRACTOR TACKLED ISSUES WITH TRANSPORTATION OF BUILDING MATERIALS BY COORDINATING TRAFFIC FLOW BETWEEN ADJACENTS STREETS AND THE MAIN ROAD, WICH IS THE MAJOR SOURCE OF TRAFFIC IN THE AREA. TO REDUCE TRAFFIC ISSUES, BUILDING MATERIALS WILL BE MOVED INTO THE SITE OVERNIGHT.
CONSTRUCTION COORDINATION WITHIN SURROUNDING BUILDINGS WOULD NOT BE DIFFICULT TO ENACT SINCE BUILDINGS SURROUNDING THE SITE ARE VERY WELL SPACED OUT.
ADDITIONAL ENGINEERING AND ENGINEERING SUPPORT SYSTEMS
TRANSPORTATION
VERTICAL CIRCULATION AT SYTRA TOWERS IS ACHIEVED THROUGH THE HELP OF 2 ELEVATORS LOCATED AT THE CENTER OF BUILDING AND 2 STAIRWELLS (ONE AT THE CENTER, AND THE OTHER AT THE EDGE OF THE BUILDING). THE ELEVATORS AND THE STAIRWELL AT THE CENTER ARE ENCLOSED BY THE CONCRETE SHEAR WALL CORES. IN ADDITION TO THE STAIRWELLS AND ELEVATORS, THERE IS A GRAND CURVED STAIRCASE CONNECTING THE BANKING HALL (1ST FLOOR) TO THE 2ND FLOOR.
FIRE PROTECTION
SINCE THE BUILDING'S STRUCTURAL SYSTEM IS MADE ENTIRELY OUT OF REINFORCED CONCRETE, WALLS (ESPECIALLY THOSE SURROUNDING THE MEANS OF EGRESS) AND FLOOR ASSEMBLIES HAVE AT LEAST 2 HR. FIRE RATINGS.
DURING A MAJOR DISASTER SUCH AS A FIRE, EGRESS FROM THE BUILDING IS ENSURED USING THE 2 STAIRWELLS.
SPECIAL SYSTEMS AND TECHNOLIGIES
IN ORDER TO ENSURE THE PRIVACY OF THE OWNER, ACESS OF TO THE 11 FLOOR (THE PENTHOUSE) IS LIMITED. HOWEVER, THE GYM (WHICH IS ACCESSIBLE BY ALL RESIDENTS) IS ALSO LOCATION ON THE 11TH FLOOR AS WELL. TO REACH THIS GOAL, AN INDENTIFICATION SYSTEM IS PLACED AT THE ELEVATOR THAT LEADS TO THE HALF OF THE 11TH FLOOR CONTAINING THE PENTHOUSE.
PRIMARY ENGINEERING SYSTEMS