Multi-storey buildings

Doc. Ing. Hana Gattermayerova,CScgatter@fsv.cvut.cz

Contents Multi strorey buildings

– Definition

– Features

Statical systems– Interior

– Extrior

Materials

Sources, literature Hájek P. a kol.:

Konstrukce pozemních staveb 1 – Nosné konstrukce I, skriptum ČVUT, Praha 2006

Ching, F.: Building structures illustrated

http://skyscraperpage.com http://theconstructor.org/st

ructural-engg/high-rise-structures/5/

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Definition

Definition➔10 stories or more➔or 30 m (100 feet) more

Various definition:

Buildings between 23 m and150 m high are considered high-rises.

Buildings taller than 150 m are classified as skyscrapers.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Definition

Definition of high-rise building (Council on Tall Buildings):

A tall building is not defined by its height or number of stories. It is a building in which „tallness“ strongly influences planning, design and use. The height of this building creates different conditions in the design, construction, operation...

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Definition

Fire definition

Certain height above the lowest level of fire department vehicle access (Building Code, ČSN 73 0802....)

ČSN 73 0810 – Požární bezpečnost staveb – Společná ustanovení - Fire protection of buildings – General requirements

ČSN 73 0802 – Požární bezpečnost staveb -Fire protection of buildings – Non-industrial buildings

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Definition

fire height (ČSN) hp:

hp < 12 m

12 m < hp ≤ 22,5 m

hp > 22,5 m

hp

floor

basement

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Feature

office building

residential buildings

multi-functional buildings

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems

High-rise buildings are dividing into two categories, based on the dominant location of the vertical lateral - resisting systems:

Interior Structures

Exterior structures

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Interior Structures

Interior Structures resist lateral load primarily through

lateral-force-resisting elements located within the interior of the structure

interior elements are constructed into a closed system that acts as a structural tube

Types of interior structures:

Rigid frame

Braced frame

Shear wall coreRigid frame

Braced frame cores

Shear wall cores

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Interior Structures

Recomended number of Stories

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Exterior Structures Resist lateral load primarily

through lateral-force-resisting elements located along the perimeter of the structure

Types of interior structures:Braced frames

Tube structures

Tube-in-tube Structures

Diagrid Structure

Trussed Tubes

Bundled Tubes

Space Truss

Megaframe Structures Braced Frames

Tube Structures

Tube-in-tube Strucrures

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Diagrid Structure

Trussed Tubes

Bundled Tubes

Space Truss Megaframe

Structures

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Recomended number of Stories

20

40

60

80

100

120

140

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Rigid Frame Structure

Consist of columns and girders joined by moment resistant connections. Lateral stiffness of a rigid frame bent depends on the bending stiffness of the columns, girders, and connection in the plane of the bents. Ideally suited for reinforced concrete buildings because of the inherent rigidity of reinforced concrete joints. Also used for steel frame buildings, but moment-resistant connections in steel tend to be costly.

Buisness Men´s Assurance, Kansas City, USA

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Advantages of rigid frames:

May be place in or around the core, on the exterior, or throughout the interior of the building with minimal constraint on the planning module.

The frame may be architecturally exposed to express the grid like nature of the structure.

The spacing of the columns in a moment resisting frame can match that required for gravity framing.

Bank, Kasas City, USA

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Vince's St. Louis, USA:B131 - Drury Plaza Hotel. Built with the seldom used Vierendeel truss system creating a rigid steel frame expressed in a stainless steel grid

Disadvantages of rigid frames:

Only suitable for building up to 20 –30 stories only

Member proportions and materials cost become unreasonable for building higher than that.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Braced Frame Structures

Braced frames are cantilevered vertical trusses resisting laterals loads primarily through the axial stiffness of the frame members.

The effectiveness of the system, as characterized by a high ratio of stiffness to material quantity, is recognized for multi-storey building in the low to mid height range.

Generally regarded as an exclusively steel system because the diagonal are inevitably subjected to tension for or to the other directions of lateral loading.

Able to produce a laterally very stiff structure for a minimum of additional material, makes it an economical structural form for any height of buildings, up to the very tallest.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Advantages of braced frames

Girders only participate minimally in the lateral bracing action-Floor framing design is independent of its level in the structure.

Can be repetitive up the height of the building with obvious economy in design and fabrication.

Disadvantages

Obstruct the internal planning and the locations of the windows and doors; for this reason, braced bent are usually incorporated internally along wall and partition lines, especially around elevator, stair, and service shaft.-Diagonal connections are expensive to fabricate and erect.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior/Interior Structures

Shear Wall Structure

Concrete or masonry continuous vertical walls may serve both architecturally partitions and structurally to carry gravity and lateral loading. Very high in plane stiffness and strength make them ideally suited for bracing tall building. Act as vertical cantilevers in the form of separate planar walls, and as non-planar assemblies of connected walls around elevator, stair and service shaft. Well suited to hotel and residential buildings where the floor-by floor repetitive planning allow the walls to be vertically continuous and where they serve simultaneously as excellent acoustic and fire insulators between rooms and apartments.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior/Interior Structures

Shear Wall Structure Tensile reinforcement for areas where tension stresses occur in walls when wind uplifts stresses exceeds gravity stresses.

Individual shear walls, at the edge of a tall building, are design as blade walls or as columns resisting shear and bending as required.

High strength concrete has enable wall thickness to be minimized, hence maximizing rentable floor space. Burj Dubai, Dubai, Arab

Emirates

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Jean Nouvel: 53 West 53rd, NY

Diagrid structure

Is a design for constructing tall buildings with steel that creates triangular structures with diagonal support beams. It requires less structural steel than a conventional steel frame.

Norman Foster:30 St Mary Axe, London, UK

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

The Trussed tube

The trussed tube system represents a classic solution for a tube uniquely suited to the qualities and character of structural steel.

Interconnect all exterior columns to form a rigid box, which can resist lateral shears by axial in its members rather than through flexure.

Introducing a minimum number of diagonals on each façade and making the diagonal intersect at the same point at the corner column.

Relatively broad column spacing can resulted large clear spaces for windows, a particular characteristic of steel buildings.

John Hancock Building, Chicago, USA

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

The Trussed tube

The Onterie Center in Chicago interpreted the trussed-tube structural system for reinforced concrete construction.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Space trussThe Hong Kong Bank of China Tower

has an externally visible truss structure.

The whole structure is supported by the five steel columns at the corners of the building, with the triangular frameworks transferring the weight of the structure into these five columns. It is covered with glass curtain walls.

Bank of China, Hong Kong Bank_of_China_Tower_model.png

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Tube-in-Tube or Hull Core Structure

This variation of the framed tube consists of an outer frame tube, the “Hull,” together with an internal elevator and service core.

The Hull and core act jointly in resisting both gravity and lateral loading.

The outer framed tube and the inner core interact horizontally as the shear and flexural components of a wall-frame structure, with the benefit of increased lateral stiffness.

The structural tube usually adopts a highly dominant role because of its much greater structural depth.

Tabung Haji Building, Designed by Hijas Katsuri, Kuala Lumpur, Malaysia

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Bundled-Tube structures

The concept allows for wider column spacing in the tubular walls than would be possible with only the exterior frame tube form.

The spacing which make it possible to place interior frame lines without seriously compromising interior space planning.

The ability to modulate the cells vertically can create a powerful vocabulary for a variety of dynamic shapes therefore offers great latitude in architectural planning of a tall building.

Sears Tower – Chicago, USA

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Sears Tower – bundled tube

The building is constructed of nine 75-foot-square tubes of welded steel that extend between 50 and 108 stories high. Floors are suspended within the tubes.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings Statical systems – Exterior Structures

Megaframes StructuresThe structural efficiency is obtained

from the concentration of material close to the corners. Each of these vertical legs is required to be stiff in its own plane. The legs then take the form of a diagonalized truss chord. The corner truss legs need strong horizontal connections at frequent modular intervals to make them function together like an equivalent cantilever. The horizontal members, therefore, will need to be equally stiff, and are diagonalized as well.

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings - Materials

The materials used for the structural system of high-rise buildings are reinforced concrete and steel. Most skyscrapers have a steel frame, while residential buildings are usually constructed out of concrete.

SteelDrawn steel sections

2014/2015 124BS01 (124BSE) Lecture 4

Multi-storey buildings - MaterialsConcrete

in-situ concrete

moving formwork (posuvné)

permanent formwork (ztracené)