deep basement

INTERNATIONAL FINANCIALCENTRE , HONG KONGBUILDING CONSTRUCTION- DEEP BASEMENT

INTRODUCTIONSITE AREA: ABOUT 20000 SQ MGENERAL CHARACTERISTICS• LIKE TYPICAL HONG KONG THE SITE HAS DEPOSITION OF GRADE IIIGRANITE AND ALUVIUM AT THE HEIGHT OF -35 M • SILL AT THE HEIGHT OF -20M• 5-LEVEL BASEMENT CONSTRUCTED USING TOP-DOWN ARRANGEMENT• BASEMENT WORKS INVOLVED- PORTION UNDER THE MAIN TOWER- PORTIUM UNDER THE RETAIL PODIUM• A 71M DIAMETER COFFERDAM DOWN TO – 35M WAS CONSTRUCTED TO• FORM THE RAFT FOUNDATION FOR THE BUILDING CORE OF THE MAIN TOWER• PORTION UNDER THE RETAIL PODIUM WAS CONSTRUCTED USING TOP-DOWNAPPROACH

PROCESS• INITIALLY THE 71M DIA COFFERDAM AND THE MEGA COLUMNS ALONG WITH THE CORE WALL

WERE CONSTRUCTED.• THEN THE CAR RAMP ON THE LEFT • FOLLOWING THE TOP DOWN METHOD THE GROUND FLOOR IS CREATED BY EXCAVATION AND

THEN ALSO A PIT CALLED DOUBLE BIT HELPS IN CARRYING THE SPOILS FROM THE EXCAVATION• THEN THE DIAPHRAGM WALLS ON THE SUBSEQUENT SIDES ARE BROUGHT DOWN TO ALLOW

ENTRY • THE SAME PROCESS IS REPEATED VERTICALLY AND HORIZONTALLY TO CREATE LEVELS BELOW• WHEN NEEDED THE EXPOSED STRUCTURAL ELEMENTS LIKE COLUMNS ARE THEN PRECASTED

FOR FURTHER PROTECTION AND STRENGTHENING

THE USE OF A MATERIAL HOIST FOR THE REMOVAL OF SPOIL FROM THE BASEMENT INTERIOR

MUCK OPENING PROVIDED ON THEGROUND SLAB FOR THE REMOVAL OF SPOIL

EXCAVATION INSIDE THE BASEMENT

CONSTRUCT THE BASEMENT IN A “DOUBLE BIT” MANNER

FORMING THE BASEMENT SLAB AND ENCASING THE STANCHION TO FORM THE COLUMN

THANK YOU

RIZVI COLLEGE OF ARCHITECTURE

HATIM MERCHANT 1232

SHAHKHIZER SHAMSI 1367

AHMED BATLIWALA 1306