1 General Provisions
1.0.1 This Specification is formulated with a view to realizing reasonable application of concrete structure (including steel and concrete mixed structure), safety and usability, advanced technology, economy and rationality, as well as convenient construction during the tall building engineering.
1.0.2 This Specification is applicable to the concrete structures of residential building of 10 stories and above or with building height greater than 28m, or the other tall civil building with building height greater than 24m. As for the tall civil buildings of non-seismic design or of seismic design in Intensity 6~9 seismic precautionary intensity, the applicable maximum height and structure type shall meet the relevant requirements of this Specification.
This Specification is not applicable to the tall buildings built in the dangerous areas or within the minimum avoidance distance of seismogenic fault.
1.0.3 Supplementary analysis and argumentation may be carried out for the concrete structures of tall building adopting seismic design by performance-based seismic design of structure, where the building height, regularity and structure type exceeds the requirements of this Specification, or there are special requirements in seismic precautionary criterion.
1.0.4 As for tall building, conceptual design, structural selection, and regularity of plane and vertical plane layout shall be emphasized; constructional measures shall be strengthened; structure system with good seismic protection and wind resistance as well as economic rationality shall be selected preferentially. During the seismic design, the integral seismic performance shall be ensured to make the integral structure have necessary bearing capacity, rigidity and ductility.
1.0.5 During the design and construction of concrete structures of tall building, not only the requirements stipulated in this Specification, but also those in the current relevant ones of the nation shall be complied with.
2 Terms and Symbols
2.1 Terms
2.1.1 Tall building, tall building
It refers to the residential building of 10 stories and above or with building height greater than 28m, or the other tall civil building with building height greater than 24m.
2.1.2 Building height
It refers to the height from the outdoor ground to the major roof of building, excluding the height of elevator machine room, water tank and frame that protrude out the roof.
2.1.3 Frame structure
It refers to the structure, composed of beams and columns as the primary member, bearing the vertical and horizontal actions.
2.1.4 Shearwall structure
It refers to the structure, composed of shearwall, bearing the vertical and horizontal actions.
2.1.5 Frame-shearwall structure
It refers to the structure, jointly bearing the vertical and horizontal actions by frame and shearwall.
2.1.6 Slab-column shearwall structure
It refers to the structure, composed of beamless floor slab and column, jointly bearing the vertical and horizontal actions by slab-column frame and shear wall.
2.1.7 Tube structure
It refers to the building, mainly composed of the vertical tube, bearing the vertical and horizontal actions. Tubes in the tube structures are divided into the thin-wall tubes enclosed by shearwalls and frame tubes enclosed by thick-column frames or wall frames.
2.1.8 Frame-corewall structure
It refers to the tube structure composed of core tube and peripheral spare-column frame.
2.1.9 Tube in tube structure
It refers to the tube structure composed of core tube and peripheral frame tube.
2.1.10 Mixed structure, hybrid structure
It refers to the building, composed of steel frame (frame tube), section steel concrete frame (frame tube), steel pipe concrete frame (frame tube) and reinforced concrete core tube, jointly bearing the horizontal and vertical actions.
2.1.11 Structural transfer member
It refers to the structural members arranged for the structrual form transfer from the upper stories to the lower stories or for the structural layout change from the upper stories to the lower stories, including transfer beam, transer truss and transfer slab. Transfer beams of some frame-supported shearwall structures are also called frame-supported beam.
2.1.12 Transfer story
It refers to the story arranged with structural transfer members, including horizontal structural members and the vertical structural members below them.
2.1.13 Story with outriggers and/or belt members
It refers to the story arranged with horizontal extension arm structure (beam or truss) connecting inner tube and peripheral structure, if necessary, ribbon horizontal truss or beam may be arranged along the peripheral structure of the story.
2.1.14 Towers linked with connective structure(s)
It refers to the structure with connective structure between two or more towers, except the podium building.
2.1.15 Multi-tower structure with a common podium
It refers to the structure with two or more towers on the upper part of podium building unseparated by the structural joint.
2.1.16 Performance-based seismic design of structure
It refers to the structural seismic design based on the seismic performance objectives of structure.
2.1.17 Seismic performance objectives of structure
It refers to the seismic performance level of structure set aiming at the ground motion levels of different earthquakes.
2.1.18 Seismic performance levels of structure
It refers to the definition for seismic performances of structure such as post-disaster damage conditions and continue-to-use possibilities.
2.2 Symbols
2.2.1 Mechanical property of material
C20—Concrete strength grade of which the standard value for its cube strength is 20N/mm2;
Ec—Elastic modulus of concrete;
Es—Elastic modulus of reinforcement;
fck, fc—Standard value and design value of axial compressive strength of concrete respectively;
ftk, ft—Standard value and design value of axial tensile strength of concrete respectively;
fyk—Standard value of ordinary reinforcement strength;
fy, —Design value of tensile and compressive strength of ordinary reinforcement respectively;
fyv—Design value of tensile strength of transverse reinforcement;
fyh, fyw—Design value of tensile strength of horizontally and vertically distributed reinforcement in shearwall respectively.
2.2.2 Action and action effect
FEk—Standard value of the total horizontal seismic action of a structure;
FEvk—Standard value of the total vertical seismic action of a structure;
GE—Representative value for total gravity load of structures in the case of calculating seismic action;
Geq—Representative value for equivalent total gravity load of structures;
M—Design value of bending moment;
N—Design value of axial force;
Sd—Design value of load effect or in combination of load effect and seismic action effect;
V—Design value of shear force;
w0—Basic wind pressure;
wk—Standard value of wind load;
△Fn—Standard value of the additional horizontal seismic action at the top of structure;
△u—Inter-story displacement of story
2.2.3 Geometric parameters
as, —Distance from the resultant force point of longitudinal tensile and compressive reinforcement to the near side of section respectively;
As, —Sectional area of longitudinal reinforcement in the tensile zone and compressive area respectively;
Ash—Total sectional area of horizontally distributed reinforcement of shearwall;
Asv—Total sectional area of each limb of stirrup in the same section of beam and column;
Asw—Total sectional area of vertically distributed reinforcement of shearwall web;
A—Sectional area of shearwall;
Aw—Area of shearwall web in T-shaped or I-shaped section;
b—Rectangular section width;
