Advanced Floor Structures By Professor Chen Shiming 2015
By Professor Chen Shiming 2015 Advanced Floor Structures
Introduction >In modern building constructions,the increasing demands of long span floors but with shallow floor depth have led to the development of various composite floor systems. >In conventional composite floor systems,the depth of beam section normally increases with the length that the floor spans over and it results in the steel sections of the ordinary down stand composite beams being heavier and deeper than expected. The height of the floor is usually about 400mm and the composite beam is at least 600mm
Introduction ➢ In modern building constructions, the increasing demands of long span floors but with shallow floor depth have led to the development of various composite floor systems. ➢ In conventional composite floor systems, the depth of beam section normally increases with the length that the floor spans over and it results in the steel sections of the ordinary down stand composite beams being heavier and deeper than expected. ➢ The height of the floor is usually about 400mm and the composite beam is at least 600mm
> Composite slim floor systems were developed in the 1990s in the UK to provide floor systems with a minimum constructional depth.The feature is the steel beam contained within the slab depth,resulting in a flat appearance. >Several arrangements of beams and slabs can be used to obtain the structural floor system;however the beam always is contained within the slab depth They have several advantages ①shallow floor depth; ② inherent fire resistance; 3 benefits in terms of cost
➢ Composite slim floor systems were developed in the 1990s in the UK to provide floor systems with a minimum constructional depth. The feature is the steel beam contained within the slab depth, resulting in a flat appearance. ➢ Several arrangements of beams and slabs can be used to obtain the structural floor system; however the beam always is contained within the slab depth . They have several advantages : ① shallow floor depth; ② inherent fire resistance; ③ benefits in terms of cost
Mesh reinforcement Tie member Cast in place concrete Steel deck Asymmetric steel beam Mesh In situ concrete Reinforcement bar Asymmetric Steel deck. Steel Beam. Ordinary down-stand composite beams Composite slim floor systems
Ordinary down-stand composite beams Composite slim floor systems
Slim floor systems The increasing demand of long span beams and shallow floor depth had led to the development of various slim floor systems. Slimflor system 月0000000000 Deltabeam system iTECH system Ultra Shallow Floor Beam
Slim floor systems The increasing demand of long span beams and shallow floor depth had led to the development of various slim floor systems. Slimflor system Deltabeam system iTECH system Ultra Shallow Floor Beam
Research on composite slim beams Experimental studies have been conducted by many researchers.The key technical problems are: Effective width of concrete slab Equivalent elastic stiffness Shear connection design ·Vibration comfort
Research on composite slim beams Experimental studies have been conducted by many researchers. The key technical problems are: • Effective width of concrete slab • Equivalent elastic stiffness • Shear connection design • Vibration comfort
Shallow Cellular Slim Floor Beam A composite Shallow Cellular Slim Floor Beam (SCSFB )system with the steel beam embedded within the depth of the floor with regularly spaced openings along the steel web filled with concrete is a new type of Slim Floor system Shallow cellular floor Shallow cellular floor using steel decking and using precast floor units cast in place concrete
Shallow Cellular Slim Floor Beam A composite Shallow Cellular Slim Floor Beam (SCSFB ) system with the steel beam embedded within the depth of the floor with regularly spaced openings along the steel web filled with concrete is a new type of Slim Floor system. Shallow cellular floor using steel decking and cast in place concrete Shallow cellular floor using precast floor units
Shallow Cellular Slim Floor Beam:It offers important benefits in terms of cost (long spanning capabilities without or with fewer secondary beams, shallow floor depth,inherent fire resistance,etc...),as well as others advantages offered by conventional composite beams construction. >Compared to others trade mark of slim floor systems,the SCSFB presents some important advantages such as: The service integration:The web openings provide the structural depth,minimizing the overall floor depth.Full service integration can be achieved when the deep profile decking is employed for the ducting passing between the ribs of the decking
➢ Shallow Cellular Slim Floor Beam: It offers important benefits in terms of cost (long spanning capabilities without or with fewer secondary beams, shallow floor depth, inherent fire resistance, etc…), as well as others advantages offered by conventional composite beams construction. ➢ Compared to others trade mark of slim floor systems, the SCSFB presents some important advantages such as: ✓ The service integration: The web openings provide the structural depth, minimizing the overall floor depth. Full service integration can be achieved when the deep profile decking is employed for the ducting passing between the ribs of the decking
The composite action The enhanced composite action due to the concrete plug passing through the web opening transfers the longitudinal shear force
The composite action The enhanced composite action due to the concrete plug passing through the web opening transfers the longitudinal shear force
The flexibility:The depth of this beam section can be designed according to the required floor depth.Typical proportion of this composite beam is 190 to 350mm for a span of 6 to 12m The inherent fire protection:The incorporation of the upper flange plates and cores of the beams in the thickness of the concrete slab provides structural protection which meet most requirements. Construction time:The beam can be used with pre-cast units and metal deck floors which eliminates the time spent for concrete hardening in the traditional beam constructions. Economic and operational:High reduction of costs can be achieved by less amount of steel used and the saving due to the stud shear connectors has to be highlighted.Another important factor is of the total life-cycle cost
The flexibility: The depth of this beam section can be designed according to the required floor depth. Typical proportion of this composite beam is 190 to 350mm for a span of 6 to 12m. The inherent fire protection: The incorporation of the upper flange plates and cores of the beams in the thickness of the concrete slab provides structural protection which meet most requirements. Construction time: The beam can be used with pre-cast units and metal deck floors which eliminates the time spent for concrete hardening in the traditional beam constructions. Economic and operational: High reduction of costs can be achieved by less amount of steel used and the saving due to the stud shear connectors has to be highlighted. Another important factor is of the total life-cycle cost