STRUCTURAL DESIGN AND COMPUTER MODELLING

Transcription

1 STRUCTURAL DESIGN AND COMPUTER MODELLING Ing. Jan Koláček, Ph.D.

2 Basic structural members 2

3 Basic structural members 3

4 Type of structures Building structures Engineering structures Bridges Air view of district Brno-Kohoutovice 4

5 Type of structures Building structures Engineering structures Bridges Oil tanks in Loukov 5

6 Type of structures Building structures Engineering structures Bridges Willamette river Bridge in Oregon, USA 6

7 1. Building structures distinguished according to their purpose: housing commercial administrative manufactural agricultural stocking, etc. 7

8 1. Building structures are formed: by load bearing structures transform actions imposed on the structures by non-load bearing structures additional function Load bearing structures: vertical members walls, columns, piers horizontal members roofs, ceilings other members stairs, arches Building structures: hall structures multi-storey buildings 8

9 1. Building structures Hall structures mostly of one storey (possibly in-built storey) used as manufactural, storing, sports, exhibitory, etc. one or multi tracts, purlin/non-purlin system 9

10 1. Building structures Hall structure non-purlin system 10

11 1. Building structures Multi-storey buildings Structural systems: wall skeleton combined special According to the orientation of vertical structures they are divided into: longitudinal transversal two-ways 11

12 1. Building structures Multi-storey buildings wall systems principal member is a wall masonry, precast or cast in-situ concrete span of tracts is mostly 3-6 m (restrain disposition) transversal system (suitable for housing), longitudinal system (administrative buildings) 12

13 1. Building structures Multi-storey buildings skeleton system developed from wall system principal members are pier or column (reduction of walls) due to wind effect have to be supplied by shear walls or cores skeleton system has lower stiffness compared to wall system better variability of arrangement Basic division of skeleton system: framed non-framed 13

14 1. Building structures Multi-storey buildings skeleton system - framed columns are jointed with horizontal beams supporting floor slab recommended material is cast in-situ, precast or prestressed concrete cross frames resist well to the wind (higher stiffness) for high-rise buildings longitudinal frames for common buildings only 14

15 1. Building structures Multi-storey buildings skeleton system non framed slab with column head flat slab combined 15

16 1. Building structures Multi-storey buildings skeleton system non framed Column heads skeleton system better safety against punching shorter span of slabs with high load bearing capacity manufacturing and storing halls Flat slab skeleton system shall be more reinforced around columns (punching) flat ceiling suitable for common houses 16

17 1. Building structures Multi-storey buildings combined combination of wall and skeleton systems many variants longitudinal wall system combined with skeleton system, two-ways skeleton system with core, etc. suitable for high-rise buildings (skyscraper), undermined areas and seismic active area 17

18 2. Engineering structures Special structures (difficult static and structural solution): underground water technological towers, masts and chimneys special 18

19 2. Engineering structures Underground structures foundation structures various underground structures Foundation structures are: shallow foundation spread footings, combined footings and mat foundations 19

20 2. Engineering structures Underground structures foundation structures various underground structures Foundation structures are: deep foundation piles, micropiles, wells and caissons 20

21 2. Engineering structures Underground structures foundation structures various underground structures Various underground structures are used: for transport (railway, traffic, pedestrian, etc.) for water service (water supplies, etc.) for energetic (telecommunication, cables, collector, etc.) halls (hydroelectric power station, gas reservoirs, water tank, sewerage plants, etc.) 21

22 2. Engineering structures Water structures dominant material is plain concrete, reinforced concrete and steel For example : dams weirs lock chambers hydro power stations pumped-storage hydro power station 22

23 2. Engineering structures Technological structures For example: blast furnace coking plants petroleum refinery cooling towers 23

24 2. Engineering structures Towers, masts and chimneys tall slim structures suitable material is steel (towers, masts) or concrete (chimneys) For example fixed supported freestanding towers transmission masts etc. 24

25 2. Engineering structures Special structures tanks reservoirs silos pools etc. Oil tanks in Loukov 25

26 3. Bridges Bridge structures are structures built to span physical obstacles (such as a body water, valley or road) They can divided into three types: bridges (clear span greater than 2,0 m) culverts (clear span less than 2,0 m) pedestrian bridges (serve pedestrians or bicyclists) Bridge across the Swiss Bay of Vranov Lake 26

27 3. Bridges Bridge components: superstructure substructure foundation 27

28 3. Bridges Substructure abutments (external support) a wall supporting the ends of a bridge including footing, etc. piers (internal support) columns, pier shaft, web wall, etc. wingwalls 28

29 3. Bridges Substructure abutments (external support) a wall supporting the ends of a bridge including footing, etc. piers (internal support) columns, pier shaft, web wall, etc. wingwalls 29

30 3. Bridges Superstructure a part of bridges which transfer the action (reaction) of loads to substructure Bridge deck a part of superstructure which is on the top of a bridge Main structure is supporting system of the bridge 30

31 3. Bridges Type of superstructure (span type): slab beam arch vault cable-stayed suspension rigid frame etc. 31

32 3. Bridges Type of superstructure (span type): slab beam arch vault cable-stayed suspension rigid frame etc. 32

33 3. Bridges Type of superstructure (span type): slab beam arch vault cable-stayed suspension rigid frame etc. 33

34 3. Bridges Type of superstructure (span type): slab beam arch vault cable-stayed suspension rigid frame etc. 34

35 3. Bridges Type of superstructure (span type): Stays slab beam arch vault cable-stayed suspension rigid frame etc. Pylon 35

36 3. Bridges Type of superstructure (span type): slab beam arch vault cable-stayed suspension rigid frame etc. Bridge deck 36

37 3. Bridges Next classification of bridges function: railroad (railway, tram, funicular, etc.) vehicular (road, highway, etc.) pedestrian material handling migration (migration of animal) structure materials: masonry concrete steel timber composite others 37

38 Calculation models of structures Design process: definition of geometry of the structure, definition of the connecting joints (mutual connection of individual members), design of material characteristics, design of cross sections of individual members, determination of loads and load combinations, calculation (computing) of the structure, dimensioning of members and connecting joints, design (construction drawings) of the structure, production of members and blocks of the structure, assembly of the structure, construction drawings of the structure as built 38

39 Calculation models of structures can be defined as a model that simulates the behaviour of the real structure. Special notice shall be taken to the following definitions: geometry method of supporting materials of used members dimensioning of members action of loads Based on this model it is possible to perform analysis. 39

40 Types of elements Four fundamental type of elements are used bar elements surface element brick elements Bar elements Bar elements model in software IDEA StatiCa are idealized by its centre line suitable for columns, arches, ties and beams the span is not less than 3 times the overall section depth and width. according to behaviour in the structure as follows: truss compressive and tensile normal forces are dominantly beam is loaded dominantly by the loads which act predominantly perpendicular to the centre line 40

41 Types of elements Surface elements are idealized by their central surface that are either flat (plates) or curved (shells). Plate elements are slabs and walls. Walls are loaded dominantly in the centre line usually serve as bracing members of multi-story buildings section depth exceed 4x its width and the height is more than 3x the overall section depth Slabs are loaded dominantly perpendicular to the central plane minimum dimension is not less than 5x the overall slab thickness act as one-way, two-way of flat slabs (supported locally by columns) 41

42 Types of elements Surface elements are idealized by their central surface that are either flat (plates) or curved (shells). Plate elements are slabs and walls. Shells are thin-walled spatial structure supported at all edges loaded mostly by uniform load acting in the direction approximately perpendicular to the surface we distinguish simple curvature and double curvature 42

43 Types of elements Brick elements in cases where there are dimensions of the elements of all direction comparable difficult computing 43

44 Production of calculation models Elements are usually supported as following: roller - are free to rotate and translate along the surface upon which the roller rest, pinned - can resist both vertical and horizontal forces but not a moment - they will allow the structural member to rotate, but not to translate in any direction, fixed - can resist vertical and horizontal forces as well as a moment - they restrain both rotation and translation. 44

45 Production of calculation models Elements are usually connected with each other. We distinguish pin connections - has allowed rotation around a distinct axis, and prevented translation in two direction fixed connections - due to the fact that can resist vertical and lateral loads as well as develop a resistance to moment combined connections Pin and fixed connections are very common 45

46 Production of calculation models Examples of connection checking by method CBFEM 46

47 Production of calculation models calculation models made from beam elements are used for steel and timber structures in addition to beam elements surface elements (slabs, walls and shells) are used for concrete structures brick elements are suitable for detailed calculation models 47

48 Solution and computing exact manual solution usage at basic tasks numerical computer calculation in practise only this is used enables interconnection with drawings, assessments, etc. Numerical calculations - in building practice they are based on the finite element method (FEM). 48

49 Examples of FEM models Willamette river bridge in Oregon, USA 49

50 Examples of FEM models Model test of cable supported bridge 50

51 Examples of FEM models Oil tanks in Loukov 51

52 Examples of FEM models Construction work on the pedestrian bridge in Kroměříž 52

53 Examples of FEM models Pedestrian bridge over the Elbe river in Hradec Králové - competition 53

54 Examples of FEM models Tower for strap testing, Dolní Loučky 54

55 Examples of FEM models 2008 Summer Olympic games - The Beijing National Stadium (The bird s nest) 55

56 Examples of FEM models Burj Khalifa -Scyscraper in Dubai 56

57 References Procházka, J., Štemberk, P.: Concrete structures 1, Nakladatelství ČVUT, Praha, 2007 Procházka, J., Štemberk, P.: Design procedures for reinforced concrete structures, Nakladatelství ČVUT, Praha, 2009 Gartner, O., Kuda, R., Procházka, M.: Betonové konstrukce VI Zásady pro navrhování betonových konstrukcí, VUT Brno, Brno, Bajer, M., Pilgr, M., Veselka, M.: Konstrukce a dopravní stavby, Moduly BO01-MO1, Studíjní opory VUT v Brně Karmazínová, M., Sýkora, K., Šmak, M.: Konstrukce a dopravní stavby, Moduly BO01-MO2, Studíjní opory VUT v Brně Nečas, R., Koláček, J., Panáček, J.: BL12 - Betonové mosty I zásady navrhování, VUT v Brně, Brno,

58 WE BUILT TOO MANY WALLS AND NOT ENOUGH BRIDGES. ISAAC NEWTON 58