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1. Unit 2
Requirements of Tall Buildings
1.Industrialization
2.Robotics in Construction
3.Stages of site Investigation
4.Site Reconnaissance & Ground investigation
5.Field tests & Laboratory tests.
6.Foundation systems
7.Introduction to safety and Health Management System
8.Material handling considerations
9.Earthmoving equipment’s
10.Horizontal and vertical movements
11.Selection & Utility of Cranes (Tower Climbing Cranes).
1

2. Industrialisation for Construction
Def: Prefabricating in a plant the maximum number of building works with
the appropriate equipment and efficient technological and managerial
methods.
The greater the number of prefabricated components that are produced in
the plant, the fewer the on-site works required.
Thiswillsignificantlyreducethedependenceonmanuallabour,the
weather,thesiteandvariousotherconstraints.
Benefits:
• Increase productivity with less manual labour on-site.
• Reduction in site accidents with minimal need of manual workers on-site.
• Faster construction process.
• Higher quality of components attainable through careful choice of
materials, equipment and quality control.
2

3. Examples of buildings assembled using high
level prefabrication
3
CHINA,Changsta

4. Examples of buildings assembled using high
level prefabrication
4
CHINA,Changsta

5. Examples of buildings assembled using high
level prefabrication
5
CHINA,Changsta

6. structural system and components of an industrialised
building
1.Horizontal units and volumetric units are erected first.
2.The floor slabs are lifted by vacuum suction lifters attached to the crawler crane and are
placed horizontally onto the ground frames or preceding floor. They are then linked
together by a tie system (internal, transverse and peripheral ties).
3.Staircases, balcony spandrels, refuse chutes, bathroom box units and service ducts are
hoisted by cables and placed in position, aligned and secured by dowel joints and
reinforcement ties.
4.Vertical panels like walls and frames, and internal partitions are lifted and aligned on the
floor slab by dowel bars.
5.Packing mortar is applied to the joint where the panel is located and is held vertically by
temporary props. The voids of the joints are cemented and the perimeter of the exposed
joints are laid with grout seals to achieve watertightness.
6.Structural connections in the form of tie beams are formed between ver to ver, hori to
hori and ver to hori components.
7.When the grout to the joints or connections has hardened, the temporary props are
removed.
8.A 50 mm reinforced screed is then cast over the floor slab to ensure continuity.
9.To complete the whole building, the roof structure is erected with roof panels, parapet
walls, roof water tank beams and panels. 6

7. structural system and components of an industrialised
building
7

8. Design for Manufacturing and Assembly (DMA)
•Def:DMAreferstotheapplicationoffactoryconditionstoconstruction
projects,bydesigningformaximumoff-siteproductionandassembly,and
withminimumassemblyandinstallationworksonsite.
•HighlevelprefabricationincludesPrefabricatedPrefinishedVolumetric
Construction(PPVC)whichinvolvestheassemblyofwholeroomscomplete
withinternalfixtures,enablesmostworkconductedinacontrolledfactory
environment,withhighproductivitythroughautomationandbetterquality
control,muchlikeinamanufacturingprocess.
Benefits:enablesreductionintimeandmanpower,enhanceshealthand
safety,costeffectivenessandwastereduction.
8

9. PPVC rooms
9

10. Adoption of PPVC for Crowne Plaza Changi Airport
Hotel Extension
10

11. Robotics in Construction
•Thecasting,erection,jointing,connectionandfinishingofbuilding
componentsrequireahighlevelofskilledmanualworkon-site.
•Theproblemwiththeshortageofskilledpersonnelandtheneedto
increaseproductivityintheindustryhaspromptedgreaterdemandfor
roboticsintheconstructionindustry.
•Buildingautomationrangesfromasingletaskrobotsthatcanreplace
simplelabouractivities(tilelaying,concretespraying,highpressurewater
jetting,surfacefinishing,reinforcementlaying)toafullyautomated
systems.
•Adv:Hazardousoperationsfromtunnelling,deepbasementexcavation,
underwaterconstructionanddemolition,toacompleteconstructionand
deconstructionoperationoftallbuildings.
11

12. •Shimizu’sSMARTsystem
Obayashi’sBigCanopysystem
Taisei’sT-Upsystem
Takenaka’sRoofPush-UpConstructionMethod
Kajima’sAMURADsystem.
•anindoorfactory-likeworkingenvironmentshelteredfrombadweather,
andequippedwithheavytransportationtechnologyforstandardised
prefabricatedelement.
•Buildingcomponentsandmaterialsaredeliveredtothefloorunder
constructionthroughelevatorsandareliftedtotheexactlocationofthe
floorbycranes.Weldingandfasteningarethencarriedoutbyrobots.
•Uponcompletionofonefloor,thefactoryisjackedupthroughaninternal
climbingsystemtocommenceworkonthenextfloor.
•Anothersystemforreinforcedconcretebuildingnamed“BigCanopy”
integratestechnologiesofclimbingcanopy,prefabricatedcomponents,
automatedassemblyandcomputerisedmanagementsystems12
Robotics in Construction

13. 13
Obayashi’s “Super Construction Factory” -steel structures.

14. Big Canopy
14
•provides protection for
the floor under
construction from
unfavourable weather
and environmental
conditions.
•Independent tower crane
posts are used as four
columns supporting the
canopy.
•The rise of the canopy is
performed by the
climbing equipment of
tower crane.
•Vertical movement of
materials to and from the
working story is by the
use of lifts and horizontal
movement by hoists.
•The movement of the
hoists is entirely
automated to improve
work efficiency.

15. Examples of attempted Robotics in Construction
15
Product
Name
Company Climbing
Mechanism
Example
The SMART
System
(the Shimizu
Manufacturi
ng
System by
Advanced
Robotics
Technology)
Shimizu-
1990
A hat-truss is
supported by four
jacking towers,
operated by
hydraulic jacks. The
hat-truss is
jacked up to working
height for the
construction of the
first storey and
repeat
Roof Push-
up
Takenaka-
1990
Push-up floor(roof )
is first constructed.
Push up RF,
construct the 1st
floor, then push
up the roof floor,
construct the 2nd
floor and repeat

16. Examples of attempted Robotics in Construction
16
Product
Name
Company Climbing
Mechanism
Example
ABCS
(Automated
Building
Construction
System)
Obayashi-
1990
Super Construction
Factory
(SCF), a working space
on a
pre-assembled roof,
supported on
building under
construction
T-Up System
(Totally
Mechanised
Construction
System)
Taisei and
Mitsubishi
-1992
With the building core
as the
support, the
production platform
is elevated with
hydraulic jacks
to the desired floor
along guide
columns

17. Examples of attempted Robotics in Construction
17
Name Company Climbing Mechanism Example
The Big
Canopy
Obayashi -
1995
With four external tower masts
and a gigantic canopy at the top.
Gantry cranes are fixed to the
underside of the canopy operated
by remote control. The canopy is
jacked up two storeys per lift.
AMURAD
(Automatic
Uprising
Constructi
on
by
Advanced
Technique)
Kajima -
1996
Building top floor down, starting
from roof and top floor and
working down until the ground
floor. Lower floor levels as the
construction factory, build the
roof floor first, push up using
hydraulic hacks by one level,
allowing work to begin for the
next floor, push up and repeat

18. Examples of attempted Robotics in Construction
18
Product
Name
Company Climbing
Mechanism
Example
FACES
(The Future
Automated
Construction
Efficient
System)
Penta-
Ocean-1997
A steel frame unit as a
canopy housing a
computer control
centre, crane robots
and automated
equipment, all
attached to the
ceiling of the
structure. The frame
is lifted along the
pillars of the
building to the next
floor level and
repeat

19. Unit 2
Requirements of Tall Buildings
1.Industrialization✓
2.Robotics in Construction ✓
3.Stages of site Investigation
4.Site Reconnaissance & Ground investigation
5.Field tests & Laboratory tests.
6.Foundation systems
7.Introduction to safety and Health Management System
8.Material handling considerations
9.Earthmoving equipment’s
10.Horizontal and vertical movements
11.Selection & Utility of Cranes (Tower Climbing Cranes).
19

20. Site Investigation
•Site investigation is considered the most important part of
any project (avoid unexpected problems)
•The risk associated with undertaking a project without
adequate site investigation is monumental.
•Reliable information obtained from a site investigation
report is what enables designers to design strong and lasting
civil projects.
•Site investigation is unique to every project and should be
planned based on the project requirements. (specific)
•Guidelines:TheASTM'sgeotechnical engineering standards
are developed to aid in specifying, testing and investigating
the properties of surface and subsurface materials relevant
to a specific project.
20

21. Why?
•Structures that are sensitive to settlement such as machine foundations
and high-rise buildings usually require a thorough soils investigation
•The type and extent of the site investigation-money-risk.
•Some local building codes have provisions that set out the extent of a site
investigation.
•It is mandatory that a visit be made to the proposed site.
•To know the allowable bearing capacity of foundation for proposed
building.
•To decide the depth and type of foundation for the proposed building.
•To know the allowable passive resistance for the foundation of proposed
building.
21
Siteinvestiationdependsonthetype,size,andimportanceofthe
structure,theclient,theengineer'sfamiliaritywiththesoilsatthesite,
andlocalbuildingcodes.

22. Why?
•To know the type, grading and nature of soil.
•To access the general suitability of the site.
•To achieve safe and economical design of foundations and temporary works.
•To know the nature of each stratum and engineering properties of the soil
and rock, (design and mode of construction of proposed structure and
foundation)
•To foresee and provide against difficulties that may arise during construction
due to ground and other local conditions.
•To find out the sources of construction material and selection of sites for
disposal of water or surplus material.
•To ensure the safety of surrounding existing structures.
•To locate the ground water level and possible corrosive effect of soil and
water on foundation material.
22

23. Stages of site Investigation
StageI-Datacollection&studyofMaps
StageII-Reconnaissancesurvey
StageIII-GroundInvestigation&LABtests
StageIV-ReportPreparation
23
4 stages

24. I-Data collection & study of Maps
•Collectionofavailableinformation-localmunicipalities,libraries,
countyrecordandsurveyoffices,utilityandserviceproviders,and
fromcommercialdatabasesthroughtheinternet
•siteplan,type,size,loadingconditions
•windprofiles,pastseismicityreport
•previousgeotechnicalreports,topographicmaps
•aerialphotographs,geologicmaps,hydrologicalinformation
•old plans and photographs can be obtained from the survey or records
department.
•Presence of licensed water abstraction and discharge consents,
landfills, and waste disposal sites
•History, if any, of hazardous incidents
•Quality of surface water andgroundwatervulnerability
•Past localboreholerecords
•Presence of coal and other mines
•Buried and overhead supply and utility lines
24

25. II-Reconnaissance Survey
•site visit
•topography and geology of the site
•information gathered in stage I is compared with the current
conditions of the site
•visual inspection is done to gather information on topography, soil
stratification, vegetation, water marks, ground water level and type of
construction nearby.
•Topography of the land including water bodies, estuaries, reserved
land and quarries
•Slopes' angles and orientation
•Presence of structures, heritage structures, trees and utility lines
•Presence of hazardous industries or waste disposal sites that could be
potential public health hazards
•Areas with loose soil, patches of soil discoloration, excess growth of
vegetation or foul smell
•Comparison of available plan with current situation, i.e., addition of
new structures or utility lines
25

26. III-In depth Investigation & LAB tests
•Detailedsoilsexploration
•detailedplanningforsoilexplorationintheformtrialpitsor
borings,theirspacinganddepth.Accordingly,thesoil
explorationiscarriedout.
•Thedetailsofthesoilsencountered,thetypeoffieldtests
adoptedandthetypeofsamplingdone,presenceofwater
tableifmetwitharerecordedintheformofborelog.
•Thesoilsamplesareproperlylabeledandsenttolaboratory
forevaluationoftheirphysicalandengineeringproperties.
26

27. Steps involved in ground investigation
•Details planning for the sequence of operations
•Collecting the samples of soil from the plot.
•Determining the soil characteristics by conducting field
tests.
•Study the condition of ground water level.
•Collecting ground water sample for chemical analysis.
•Soil exploration.
•Testing all collected samples in the laboratory.
•Analysis the test results.
•Preparing report.
27

28. Tests-in situ
•Direct methods –(sampling-testing)-boreholes, probes and trial pits
•Indirect methods-sounding and geophysical methods.
•
1. Boreholes
-less disruptive to the surface than trial pits-a greater depth-any type of subsurface
strata -In this method several bore holes are made for the purpose of collecting soil
sample from below the ground. Then the collected sample is analyzed for preparing
the soil report.
2. Trial Pits/test pits
-pits are excavated in soils that can support themselves for the required time needed
to conduct the investigation-In loose soils,shoringmay be required-There are depth
restrictions in trial pits-The advantages are that it indicates vertical and lateral
variations in the subsoil strata. This is done to collect soil samples for detail analysis.
In this method several pits are dug by excavator. Several samples are collected from
the pit of both disturbed and undisturbed soil.
3. Probing
-dynamic and static cone penetration methods. Dynamic probing is similar to
astandard penetration test(SPT) and the number of blows required to drive the
cone 100 mm is recorded. In static probing, the head of the cone has a sensor that
records the resistance to driving force. The penetration and withdrawal of the steel
rod is closely observed to know the nature of soil layer.
28

29. Methods of borings
i) Auger boring –preferred for shallow depths , low ground water table
ii) Wash boring: high water table, deeper soil deposit
iii) Rotary drilling: high quality boring, also for rock drilling
iv) Percussion drilling: fast drilling, both rocks and soils
Type of project Spacing (m)
•Multistory buildings 10 –30 One-story industrial plants 20 –60
•Highways 250 –500 Residential township 250 –500
Location, spacing and depth of borings depends on:
•i) Type,size of structure
•ii) Weight coming from the structure
•General guidelines for location and depth of bore holes
Boreholes are generally located at
•The building corners ,The centre of the site
•heavily loaded columns or machinery pads are proposed.
•At least one boring should be taken to a deeper stratum, probably up to the bedrock
if practicable other borings may be taken at least to significant stress level.
29

30. Spacing of Bore Holes –Codal Recommendations
According to IS 1892 (1979) Code of practice for subsurface investigation:
•For a small building one bore hole or test pit at the centre can give necessary
data
•For a building covering not more than 4000 sq.m, one bore hole or test pit
at each corner and one at centre is adequate.
•For a large project, the number will depend on its geological features and
variation of strata. Generally a grid of 50 m spacing should be used with a
combination of bore holes and sounding tests.
30

31. Trial pits or test pits
•Applicable to all types of soils
•Provide for visual examination in their natural condition
•Disturbed and undisturbed soil samples can be conveniently obtained at different
depths
•Depth of investigation: limited to 3 to 3.5 m.
Advantages
i) Cost effective
ii) Provide detailed information of stratigraphy
iii) Large quantities of disturbed soils are available for testing
iv) Large blocks of undisturbed samples can be carved out from the pits
v) Field tests can be conducted at the bottom of the pits
Disadvantages
i) Depth limited to about 6m , Deep pits uneconomical
ii) Excavation below groundwater and into rock difficult and costly
iii)Too many pits may scar site and require backfill soils.
iv) Undisturbed sampling is difficult
v) Collapse in granular soils or below ground water table
31

32. Factors
• Type, weight,Dimension of structure
• Disposition of the loaded area
• Soil profile and layer properties
Guidelines for depth of investigation:
1. At least 1 boring should be taken to deeper stratum, probably up to the bedrock
2. Borings should penetrate at least 3 m into rock.
3. Other borings may be taken at least to significant stress level.
4. In compressible soils such as clays, the borings should penetrate at least between1
and 3 times the width of the proposed foundation or until the stress increment due
to the heaviest foundation load is less than 10%, whichever is greater.
5. In very stiff clays, borings should penetrate 5-7 m to prove that the thickness of the
stratum is adequate.
6. Borings must penetrate below any fills/very soft deposits below the structure.
7. The min depth of boreholes should be 6 m unless bedrock or very dense material is
encountered.
32
Significant Depth
The investigation shall be carried out to the point at which the vertical stress due to
proposed structure is equal to or less than 10% of original effective stress at the point
before the structure is constructed

33. Penetration Tests
•These tests involve the measurement of the resistance to
penetration of a sampling spoon, a cone or other shaped tools
under dynamic or static loadings.
•The resistance is empirically correlated with some of the
engineering properties of soil as density index, consistency,
bearing capacity, etc.,
•These tests are useful for general exploration of erratic soil
profiles, for finding depth to bed rock or hard stratum, and to
have an approximate indication of the strength and other
properties of soils, particularly the cohesionless soils, from which
it is difficult to obtain undisturbed samples.
Common tests
1)Standard Penetration Test
2) Dutch Cone Test
33

34. Geophysical exploration
•to locate boundaries between different elements of the subsoil-the gravitational,
magnetic, electrical, radioactive or elastic properties of the different elements of the
subsoil may be different.
•the resistivity method based on the electrical properties and the seismic refraction
methods based on the elastic properties of the deposits have been used widely in
tall and large civil engineering projects.
34
Electrical resistivity method
based on the difference in the
electrical conductivity or the
electrical resistivity of different soils.

35. Seismic Method
•a geophysical method used for investigating subsurface ground conditions utilizing
surface-sourced seismic waves-seismic waves have differing velocities in different
types of soil-the waves are refracted when they cross the boundary between
different types of soil or rock. The methods enable the general soil types and the
approximate depth to strata boundaries, or to bedrock, to be determined.
operation
•Pulses of low frequency seismic energy are emitted by a seismic source such as a
hammer-plate, weight drop or buffalo gun,Explosives.
•The seismic waves propagate downward through the ground until they are
reflected or refracted off subsurface layers.
35
Refracted waves are detected by arrays of 24 or
48 geophones spaced at regular intervals of 1 -
10 metres
Sources are positioned at each end of the
geophone array to produce forward and
reverse wave arrivals along the array.

36. Tests-Laboratory
Laboratory Testing
The soil recovered during the in-depth soil investigation is tested in the lab at this
stage. The material obtained is classified and characterized, and based on the
project, geotechnical parameters are provided for the design phase.
Type of soil samples
•Non-Representative samples:-in which neither the in-situ soil structure, moisture
content nor the soil particles are preserved (wash boring or percussion drilling)
•Disturbed soil samples:-in which the in-situ soil structure and moisture content are
lost, but the soil particles are intact.(auguring, grab, split spoon (SPT))
•Undisturbed soil samples:-in which the in-situ soil structure and moisture content
are preserved. (Shelby tube (thin wall), piston sampler, surface (box), vacuum,
freezing)
1. Classification Test
moisture content, plasticity index, particle size distribution and bulk density.
2. Shear Strength Test,Compressibility,permeability
short-term stability, long-term stability and residual shear strength properties using
the shear box test
36

37. IV-Report preparation
•Prepareareport
•containacleardescriptionofthesoilsatthe
site,methodsofexploration,soilprofile,test
methodsandresults,andthelocationofthe
groundwater.
•informationsandexplanationsofanyunusual
soil,waterbearingstratum,andsoiland
groundwaterconditionthatmaybe
troublesomeduringconstruction.
37

38. IS CODES
• IS 1888: 1982 Method of Load Test on Soils.
• IS 1892: 1979 Code of Practice for Subsurface Investigation for Foundations
• IS 2131: 1981 Method for Standard Penetration Test for Soils.
• IS 2720: Part 31: 1990 Methods of Test for Soils -Part 31: Field Determination of California Bearing Ratio.
• IS 2911: Part 4: 1985 Code of Practice for Design and Construction Pile Foundations -Part 4 : Load Test on Piles.
• IS 4434: 1978 Code of practice for in-situ vane shear test for soils.
• IS 4453: 1980 Code of Practice for Subsurface Exploration by Pits, Trenches, Drifts and Shafts
• IS 4464: 1985 Code of Practice for Presentation of Drilling Information and Core Description in Foundation Investigation.
• IS 4651: Part 1: 1974 Code of practice for planning and design of ports and harbours: Part 1 Site investigation.
• IS 4968: Part I: 1976 Method for Subsurface Sounding for Soils -Part IBentonite Slurry.
• IS 4968: Part II: 1976 Method for Subsurface Sounding for Soils -Part II
• IS 4968: Part III: 1976 Method for Subsurface Sounding for Soils -Part II: Static Cone Penetration Test.
• IS 5249: 1992 Determination of Dynamic Properties of Soil -Method of Test.
• IS 5529: Part 1: 1985 Code of Practice for in-situ Permeability Tests -Part 1: Tests in Overburden.
• IS 5529: Part 2: 2006 In-Situ Permeability Test Part 2: Tests in Bedrock.
• IS 6926: 1996 Diamond Core Drilling -Site Investigation for River Valley Projects -Code of Practice.
• IS 6955: 2008 Subsurface Explorations for Earth and Rock-fill Dams -Code of Practice.
• IS 7720: 1991 Criteria for Investigation, Planning and Layout for Barrages and Weirs
• IS 9214: 1979 Method of Determination of Modulus of Sub-grade Reaction (K-value) of Soils in Field.
• IS 10060: 1981 Code of Practice for Subsurface Investigation for Power House Sites
• IS 13746: 1993 Code of practice for geotechnical investigation of offshore jacket structure
• IS 14592: Part 1 : 1998 Planning and Design of Barrage Power Houses -Guidelines -Part 1
• IS 15681: 2006 Geological Exploration by Geophysical Method (Seismic Refraction) -Code of Practice.
• IS 15736: 2007 Geological Exploration By Geophysical Method (Electrical Resistivity) -Code of Practice. 38

39. Unit 2
Requirements of Tall Buildings
1.Industrialization
2.Robotics in Construction
3.Stages of site Investigation
4.Site Reconnaissance & Ground investigation
5.Field tests & Laboratory tests.
6.Foundation systems
7.Introduction to safety and Health Management System
8.Material handling considerations
9.Earthmoving equipment’s
10.Horizontal and vertical movements
11.Selection & Utility of Cranes (Tower Climbing Cranes).
39

40. Foundation Systems
•Shallow foundation
–Individual footing or isolated footing
–Combined footing
–Strip foundation
–Raft or mat foundation
•Deep Foundation
–Pile foundation
–Pier foundation
–Drilled Shafts or caissons
•Special foundation
40

41. Deep Foundations
41

42. Foundation Systems for Tall Structures
• Spread foundations-strip foundations and raft
foundation
• Deep foundations-pile foundations
• Combined foundations-Combined Pile-Raft
Foundations(CPRF)
• Special foundations-caisson foundations and well
foundations
42

43. Foundation for high rise buildings
•Raft foundation
•Piled –Raft foundation
•Cellular Raft foundation
•Diaphragm walls
43

44. 44
Depth of soil investigation
Strip and single
Raft foundation
The investigation depth Za in meters
Za depends on the smaller width bFor bBof the construction

45. Pile Foundation and CPR Foundation
45
The soil investion depth Za is
depends on the width bg of the
contour of the piles for pile
group or a CPRF
The soil investion depth Za is
depends on the diameter of
the pile toe for pile foundation

46. Spread Foundation
How? transfer their loads to the subsoil only by normal stresses and shear
stresses.
Spread foundations -single foundations, strip foundations, raft foundations.
Requirement-the bearing capacity of the subsoil below the bottom of the
foundation.
If the subsoil has insufficient bearing capacity, improvement to the subsoil or
alternative foundation systems are required.
46

47. Raft Foundation
•Raft foundations are used when the load grid is dense and the deformations
of the subsoil and the construction have to be homogenized.
•Raft foundations can be used as a part of a so-called white trough, or in
combination with an additional sealing system (e.g., bitumen layers) to
prevent groundwater influx.
•The thickness of the reinforced concrete slab depends on the bending
moment, as well as on the punching (concentrated loads).
•Increasing the slab thickness or arranging concrete haunches can avoid
shear reinforcements.
•To prevent groundwater influx or to repel weather conditions, the crack
width of the concrete has to be limited.
•In any case, the installation of construction joints, expansion joints and
settlement joints has to be planned precisely and supervised during the
construction phase
47

48. Deep foundations
For the transfer of high loads into the subsoil or for subsoil with insufficient
stiffness, deep foundations are designed.
Types:
• Pile foundations
• Barrette foundations
• Combined pile-raft foundations (CPRF)
• Well foundations
• Caisson foundations
48

49. Barrettes are single diaphragm wall lamellas and
can be used analog as deep foundation
elements. (type of pile, shape can be altered)
49

50. Pile types
•Bored piles
•Driven piles
•Wood piles
•Steel piles
•Driven reinforced-concrete piles
•Driven in situ concrete piles
•Driven bored piles (screw piles)
•Micro piles
50

51. The choice of a pile type depends on the following criteria:
• Structural loads
• Location, geometry, and neighborhood
• Subsoil and groundwater conditions
• Deformation limits of the construction
• Economics
• Availability of construction materials
• Availability of construction machines
• Availability of a specialized heavy construction company
51

52. 52

53. 53

54. Combined Piled Raft Foundation
54
•A CPRF is a special form of deep foundation.
•a hybrid foundation system that combines the bearing capacity of a
foundation raft and the piles or barrettes.
•where a conventionalraft foundationdoes not provide adequate support, it
can be enhanced by the addition ofpiles-CPRF
•Pile foundationscan help transferloadsthrough weak, compressible strata
orwateronto stronger, more compact, less compressible and
stiffersoilorrockat depth.

55. •The addition ofpilesto araftincreases the effectivesizeof a foundation
and can help resisthorizontal loads. This can improve theperformanceof
the foundation in reducing the amount ofsettlementand
differentialsettlement, as well as improving the ultimateloadcapacity.
•Piled raft foundationsare typically used for largestructures, and in
situations wheresoilis not suitable to preventexcessivesettlement.
•a technically and economically optimized foundation system.
•can be used for the foundations of highrise buildings, bridges and towers.
•Due to the interaction between the foundation elements and the subsoil,
CPRFs have a very complex bearing and deformation behavior.
55
Combined Piled Raft Foundation

56. •Duringthedesignprocess,theoptimumnumberandpositionofpiles,as
wellastheirdiameter,reinforcementandlength,isdeterminedtoensure
thestabilityofthestructurewhileprovidinganeconomicalsolution,with
theraftandpilesactingtogethertoensuretherequiredsettlementisnot
exceeded.
•Typically,thepilesprovidemostofthestiffnesswhiletheraftprovides
additionalcapacityattheultimateloading.
•Ifthereareoneormoreineffectivepiles,theraftcanallowsomedegree
ofloadredistributiontootherpiles,reducingtheinfluenceof
thepile’sweaknessontheoverallperformanceofthefoundation.
56
Combined Piled Raft Foundation

57. UnconnectedPiled Raft Foundation
•In UCPRF, thepilesare not
directly connected to
theraft, but are separated
from it be astructuralfill
'cushion' (compacted
sand-gravelmixture/
compactedsoil) which
redistributesloadbetween
theraftandpiles.
•more efficient, and so
economic solution.
57

58. Advantages
• Reduction of settlements and differential settlements
• Increasing of the bearing capacity of spread foundations
• Reduction of the bending moments of the foundation raft
• Reduction of pile materials (30%–50%)
58

59. Unit 2
Requirements of Tall Buildings
1.Industrialization
2.Robotics in Construction
3.Stages of site Investigation
4.Site Reconnaissance & Ground investigation
5.Field tests & Laboratory tests.
6.Foundation systems
7.Introduction to safety and Health Management System
8.Material handling considerations
9.Earthmoving equipment’s
10.Horizontal and vertical movements
11.Selection & Utility of Cranes (Tower Climbing Cranes).
59

60. Safety and Health Management System
•Health
TheWorldHealthOrganization(WHO)definedhealthas"astateofcomplete
physical,mental,andsocialwell-beingandnotmerelytheabsenceof
diseaseorinfirmity”.
Inourcase,healthmeansbeingfreefromillness,injuryorpainwhichcanbe
causedbyconstructionactivities.
•Safety
Safetyisdefinedasarelativefreedomfromdanger,risk,orthreatofharm,
injury,orlossofpersonneland/orproperty,whethercauseddeliberatelyor
byaccident.Safetycanbedefinedasthecontrolofrecognizedhazardsto
achieveanacceptablelevelofrisk.
Inourcase,safetymeansfreedomfromdanger,harm,andinjurytotheperson
involvedinconstructionactivities
60

61. Safety Rules & Regulations (Occupational Safety & Health
Act Of 1970)
1.Use of Personal Protective Equipment and Safety Devices.
2. General Housekeeping, Stacking of Materials.
3. Road Safety inside Project.Access, Egress & Workstation Safety.
4. Safe Use of Construction Power Supply
5. Maintenance of Installations.
6. Work Permits Systems.
7. Use, Maintenance & Inspection of Construction Plant & Machinery.
8. Scaffold & Formwork Norms.
9. Use of Material & Personnel Handling Devices.
10. Fire Prevention, Protection & Preparedness.
61

62. Safety policy
62

63. Work Permit Systems
1. Excavation Clearance Permit.
2. Confined Space Entry Permit.
3. Permit To Work On Plant, Machinery & Other Power Driven Equipment.
4. Permit to Open Manhole Covers / shaft work.
5. Height work permit.
6. Hot work permit.
7. Night work permit.
8. Radiography work permit
63

64. Checklists
1.General Safety Inspection Checklist.
2. Erection Safety Checklist.
3. Safety in Scaffolding Checklist.
4. Safety while Working At Height Checklist.
5. Electrical Safety inspection Checklist.
6. Crane Inspection Checklist.
64

65. Reports
1.Site Safety Inspection Report.
2. Electrical Safety Inspection Report.
3. Crane / Vehicle / Earth Moving Equipment Inspection Report.
4. Equipment Fitness Report for Vehicle & Earth Moving
Equipment and cranes.
5. Safety Audit Report.
6. Safety Audit compliance report.
7. Safety Minutes of meeting.
65

66. Monthly Reports
1. Accident Investigation Report
2. Preliminary Accident Report
3. Dangerous Occurrence Investigation Report.
4. Monthly Site Safety Statistics.
5. Safety index.
6. Monthly man-hours report.
7. Monthly safety performance report.
66

67. 4 Eye Principle
The large number of accidents in construction projects in recent years shows
that, for safety aspects, an independent supervision and monitoring system
is necessary during planning, design, and construction.
To guarantee public safety, the four-eye principle is a vital for the verification of
analyses and designs by a publicly certified independent expert.
Publicly certified independent experts in the following fields are required:
• Structural engineering
• Fire prevention
• Technical facilities and installations
• Geotechnical engineering
67

68. •Thepubliclycertifiedindependentexpertsverifyandcertifycomplianceto
thecurrentstandardsandregulationsintheirspecificfieldofwork.
•Publiclycertifiedindependentexpertsforgeotechnicsverifyandcertifythe
completenessandaccuracyofthesoilinvestigationandtheplanning,
designandconstructionoffoundationsystems,retainingstructures,
tunnels,andsoon.
•Thefour-eyeprincipleofcivilengineeringconsistsofthreemajorparts,
Investors,expertsforplanninganddesign,andconstructioncompanies
belongtothefirstpart.Planninganddesignarebasedonthecurrent
standardsandregulationsandarepartsoftherequestforthebuilding
permission.
•Thebuildingauthoritiesarethesecondpart,andtheyindependentlycheck
complianceoftheplanningtothebuildinglaw.Thebuildingauthoritiesare
responsiblefortheindependentsupervisionofalllegalaspects.
•Thethirdpartconsistsofthepubliclycertifiedindependentexperts.They
areresponsiblefortheindependentsupervisionofallengineeringaspects
duringplanning,design,andconstruction. 68

69. 69

70. Unit 2
Requirements of Tall Buildings
1.Industrialization
2.Robotics in Construction
3.Stages of site Investigation
4.Site Reconnaissance & Ground investigation
5.Field tests & Laboratory tests.
6.Foundation systems
7.Introduction to safety and Health Management System
8.Material handling considerations
9.Earthmoving equipment’s
10.Horizontal and vertical movements
11.Selection & Utility of Cranes (Tower Climbing Cranes).
70

71. Material handling
•Handling and storing materials involve diverse operations such as hoisting
tons of steel with a crane; driving a truck loaded with concrete blocks;
carrying bags or materials manually; and stacking palletized bricks or other
materials such as drums, barrels, kegs, and lumber.
•The efficient handling and storing of materials are vital for construction
process. In addition to raw materials, these operations provide a continuous
flow of parts and assemblies through the workplace and ensure that
materials are available when needed.
•The improper handling and storing of materials often result in costly
injuries.
•Material handling can be a major problem on high-rise buildings where
items and personnel, including those belonging to subcontractors, must be
delivered to elevated locations.
71

72. To handle materials efficiently:
1.Ensure there are sufficient people and the right type of equipment to
handle them
2.make sure material transport, loading and unloading is organised and
managed properly
3.look at ways to assist with loading and offloading, such as getting the
supplier to pack and secure the items onto pallets
4.it may be necessary for deliveries to take place after-hours when cranes
will be available
5.offload material close to where it is required
6.ensure storage areas are well-planned, organised, neat, with a traffic
management system and good access roads
7.plan the project at the start to ensure there will be sufficient cranes and
access
8.sometimes just adding an extra operator can mean that the crane can
work through lunch hours and longer hours
72

73. Material handling systems
•Material handling systems mean the control of materials and products for
project use in various stages starting from manufacturing, storage,
distribution, consumption, and finally disposal.
•The system must ensure the safe handling of all project materials.
•In this process, the material handling system uses various manual,
automatic or semi-automatic equipment known as material handling
equipment.
•The material handling system basically deals with the safety of material
handling equipment & their operations.
•The material handling system is to ensure proper handling, lifting &
offloading equipment in order to ensure a safe workplace.
73

74. Advantages of MHS
•proper resource allocation
•shorten delivery time
•Forecasting
•Proper Inventory control and management
•improved Production planning
•reduce overall material handling costs
74

75. Types of MHS
•Storage Systems
•Engineered Systems
•Industrial Material Handling Trucks and
•Bulk Material Handling Equipment
75

76. Material handling Issues
1. Loading dock congestion
Loading dock congestion is a compliated problem by the fact that high-rise
buildings are often surrounded by narrow, one-way streets-little room for
trucks to wait in line for a loading dock or park outside.(Schedule deliveries
in advance)
2.Only one elevator-Small elevators-No elevator-plan ahead-Outsource
material hauling
3.Night work schedules-Schedule night deliveries
4.Limited space to lay out materials
In tall buildings, you’ll have limited floor space to prepare your materials.
Everything needs to happen inside of the building, as street space is limited -
prefab elements
76

77. The components of material handling system
•Hoisting equipment
•Monorails and workstation cranes
•Conveyors
•Casters and wheels
•Automatic guided vehicles
•Lift trucks
•Automated storage and retrieval systems
•Industrial robots, etc
Recently, automation is used in material handling systems which makes the
material handling systems more efficient to perform their job.
77

78. Heavy Lifting Machineries
Forklifts-lifting and transporting materials and goods. Height, load capacity,
fuel type, tyre, etc are a few factors one can consider while investing in
forklifts for construction sites
Cranes-facilitate lifting while constructing high rise buildings or other tall
structures.
•How high is the work to be completed? How far is the load from the crane?
•any obstacles? What material,condition is the ground beneath the crane?
Hydraulic elevators-are modern lifting gears which come with strong and
stable hydraulic tubes. These tubes are used to transport construction
materials in solid or solution form.mobile hydraulic elevators and
permanent hydraulic elevators. The first one is often used for medium
height buildings and the second one for tall buildings.
Rod Climbers-have the capacity of lifting extremely heavy loads with high
degree of precision as compared to the size it is available in.
Strand Climbers-useful for pulling, lowering as well as lifting devices that are
used on construction sites.
78

79. Earthmoving Equipments
Def: Earthmovingequipmentis heavyequipment, typically heavy duty
vehiclesdesigned forconstruction operationswhich involveearthworks.
Work:They are used to move large amounts of earth, to dig foundations
forlandscapingand so on. mainly used in theconstruction industry, but other
major applications include mining, digging and other heavydutywork.
Other names: heavytrucks, heavy machines,construction
equipment,engineeringequipment, heavyvehiclesand heavyhydraulics.
Energy: Most earthmovingequipmentuseshydraulicdrives as the primary source of
motion.
Types( operation):
•Excavators(compactexcavator,dredging,draglineexcavator, front shovel).
•Loaders(skiploaderand wheelloader).
•Constructiontractors (grader,scraper, trackloader,materialhandler).
79

80. 1. Excavators
Excavators are heavy construction equipment consisting of a boom, dipper (or
stick), bucket and cab on a rotating platform known as the “house”.
The house sits atop an undercarriage with tracks or wheels.
They are a natural progression from the steam shovels and often mistakenly
called power shovels.
All movement and functions of ahydraulic excavatorare accomplished through
the use of hydraulic fluid, with hydraulic cylinders and hydraulic motors.
Uses:
•Material handling
•Excavating trenches, holes, and foundations
•Brush cutting with hydraulic attachments
•Demolition
•Rough grading
•Heavy lifting andpipe installation
•Mining
•River dredging
80

81. 2. Backhoe loader
•A backhoe loader/ loader backhoe /digger is a heavy equipment vehicle
thatconsists of a tractor-like unitfitted with a loader-style shovel/bucket on the
front and a backhoe on the back.
•Due to its small size and versatility, backhoe loaders are very common in urban
engineering and small construction projects
•Much like the other machines, the backhoe loader can also have its buckets and
loaders removed in place of additional attachments.
81
Uses: loading, material mixing,
landscaping, battering, benching,
cutting and boxing, backfilling, lifting,
trenching, breaking rocks, and more.

82. 3. Bulldozer
A bulldozer is a tractor equipped with a substantial metal blade used to push
large quantities of soil, sand, rubble, during construction and typically
equipped at the rear with a claw (ripper) to loosen densely compacted
materials. It is usually a crawler (continuous tracked) tractor.
The blade can be lifted and tilted to adapt to a number of different tasks and
situations. The pushing technique is perfect for any jobs involving levelling
and drain cutting, as well as the dozer acting as a good old battering ram.
Modern dozers with programmable controls, that the operator simply has to
input the desired grade, before letting the machine determine the perfect
tilt and lift.
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Uses: towing, excavation in bulk, clearing
land, ripping, cut and fill, benching, mines
and quarries, military bases, heavy
industry factories, engineering projects
and farms.

83. 4. Skid-steer loader
A skid loader is a small, rigid-frame, engine-powered machine with lift arms used to
attach a wide variety of labor-saving attachments.
Turning is accomplished by differential steering, in which the left and right wheel pairs
are operated at different speeds, and the machine turns by skidding or dragging its
fixed-orientation wheels across the ground.
The extremely rigid frame and strong wheel bearings prevent the torsional forces
caused by this dragging motion from damaging the machine.
It is ideal for jobs in tighter spaces-offer good traction in snow and mud-minimize soil
compaction and damage to finished areas.
the front attachment can be switched out for a wide array of options, such as a 4 in 1
Bucket, rotary hoe, dozer blade, hammer, auger, chain trench digger, GP bucket,
pallet forks to perform digging, drilling, compacting, log grappling, snow blowing,
jack-hammering, and other tasks.
83
uses: breaking rocks, cleaning up the site,
material mixing, loading, excavating,
battering, benching, stripping soil, loading,
and much more.

84. 5. Motor grader
•A motor grader, is a construction machine with a long blade used to create
a flat surface during the grading process.
•Typical models have three axles, with the engine and cab situated above the
rear axles at one end of the vehicle and a third axle at the front end of the
vehicle, with the blade in between.
•Most motor graders drive the rear axles in tandem, but some also add front
wheel drive to improve grading capability. Many graders also have optional
attachments for the rear of the machine which can be ripper, scarifier,
blade, or compactor.
•They have a long blade that can be adjusted to meet certain angles to
create a flat surface, used to create sloped surfaces ordrainage ditcheswith
shallow V-shaped cross-sections.
84
•underground mining.
•used to fine-grade dirt or gravel roads or to
prepare the road base course before placing
asphalt.

85. 6. Trencher
•A trencher is a construction equipment used to dig trenches, especially for
laying pipes or electrical cables, for installing drainage, or in preparation for
trench warfare.
•It does this using a conveyor system in which the dirt was excavated and
deposited on the ground alongside the trench.
•Trenchers come in many different types and sizes, from small walk-behind
versions to very large trenching machines that can cut intoasphalt
pavementand other hard surfaces.
•Trenchers can use different digging implements depending on the depth of
the trench and material being excavated.
85

86. Loader
A loader is a heavy equipment machine used in construction to move aside or
load materials such as asphalt, demolition debris, dirt, snow, feed, gravel,
logs, raw minerals, recycled material, rock, sand, woodchips, etc. into or
onto another type of machinery (such as a dump truck, conveyor belt, feed-
hopper, or railroad car).
There are many types of loader, which, depending on design and application,
are called by various names, including bucket loader, front loader, front-end
loader, payloader, scoop, shovel, skip loader, wheel loader, or skid-steer.
86

87. Wheel tractor-scraper
•A wheel tractor-scraper is a piece of heavy equipment used for
earthmoving.
•The rear part of the scraper has a vertically moveable hopper with a sharp
horizontal front edge which can be raised or lowered. The front edge cuts
into the soil and fills the hopper.
•When the hopper is full it is raised, closed, and the scraper can transport its
load to the fill area where it is dumped. With a type called an ‘elevating
scraper’ a conveyor belt moves material from the cutting edge into the
hopper.
Dragline excavator
•Draglines fall into two broad categories: those that are based on standard,
lifting cranes, and the heavy units which have to be built on-site.
•Most crawler cranes, with an added winch drum on the front, can act as a
dragline. These units are designed to be dismantled and transported over
the road on flatbed trailers.
•Draglines used in civil engineering for road, port construction, pond and
canal dredging, and as pile driving rigs.
87

88. Dump truck
•A dump truck, known also as a dumper truck or tipper truck, is used for
taking dumps (sand, gravel, or demolition waste). A typical dump truck is
equipped with an open-box bed, which is hinged at the rear and equipped
with hydraulic rams to lift the front, allowing the material in the bed to be
deposited on the ground behind the truck at the site of delivery.
•After being loaded with material, the dump truck can easily transport large
quantities from A to B, before dumping them in their final destination.
•Dump trucks are needed on almost every large job site. They offer limited
functionbut perform the all-important task of moving and dumping many
types of heavy material. They are also road-ready so they can bring material
into or out of site and can travel anywhere large equipment is permitted.
88

89. Pile driver
•A pile driver is a device used to drive piles into soil to provide foundation
support for buildings or other structures.
•A pile driver uses a weight placed between guides so that it can slide
vertically. It is placed above a pile.
•The weight is raised, which may involve the use of hydraulics, steam, diesel,
or manual labour. When the weight reaches its highest point it is released,
and hits the pile, driving it into the ground.
Crawled loader
•Crawled loaders are machines with a tracked chassis and a loader that can
be used for digging and moving/loading materials.
•They are a versatile component of any fleet, able to perform many tasks.
These days, loaders are most often needed to move heavy materials on a
construction site.
•They are well-suited for moving wood chips, sand, rock and recycled
materials.
89

90. Cranes-types and selection
•A crane is a piece of heavy machinery that is a tower or platform that is
equipped with cables and pulleys -used to lift and lower materials.
•The types of cranes used in construction are generally temporary structures
and will be either fixed to the ground or mounted on a vehicle.
•The operator can control the crane from inside a cab that moves with the
crane, by radio controls or by a push button pendant control station.
•They can be used to move heavy equipment or machinery or material.
Many types of cranes can quickly and easily move equipment into trenches
or down steep hills. They can move large pipes from one place to another.
•Cranes are beneficial in the construction process for buildings, bridges and
overpasses. They are an indispensable asset to the construction and
engineering fields.
•Cranes have become a common sight on any work sight that involves heavy
lifting or the lifting on materials onto higher areas. So using proper type of
crane is important in construction works. 90

91. Types
1.Floating crane.
2.Telescopic crane.
3.Harbor crane.
4.Crawler crane.
5.Rough terrain crane.
6.All terrain crane.
7.Truck mounted crane.
8.Level Luffing crane.
9.Rail road crane.
10.Telescopic handler crane.
11.Aerial crane.
12.Tower crane.
91

92. Telescopic Crane
•Telescopic crane consists of a large boom in which some numbers of tubes
are fitted inside with each other. It increases their height with the help of
tubes through the hydraulic mechanism.
•They are especially used to transport goods from one place to another.
When it comes to transferring the object to a high place, Telescopic cranes
are the best. Because they can adjust their heights according to the place.
They can also be used in rescue operations.
92

93. All Terrain Crane:
•It is in that types of cranes which can travel at the
same speed on the public roads as well as on the off
roads. They also consist of more tires than rough
terrain cranes.
•The main difference between rough and all terrain
crane is that. Rough terrain usually travels on off
roads not on public roads, while the All terrain can
be in both
93

94. Mobile Cranes
•Basic type of crane and consists of a steel truss or telescopic boom
mounted on some kind of mobile platform. This platform could be wheeled,
a rail or even a cat truck. The boom is hinged at the bottom and can be
raised or lowered by cables or hydraulic cylinders.
•Carry deck cranesare small, four-wheeled, can rotate a full 360 degrees,
and are more portable than other types of cranes. Carry deck cranes are
simple to set up, and their small size easily allows them to navigate around
confined and open spaces, making them a staple on many job sites.
94

95. Rough Terrain Crane:
•Rough Terrain Cranes are mounted on the four rubber tires. They are
mostly used in off road applications. Outriggers are used for
stabilizing the crane while working. They contain only one engine
which means that same engine is used forundercarriageand crane.
•A normal vehicle mounted crane can not be used in off road
constructions. That’s why rough terrain cranes are used.
95

96. Level Luffing Cranes:
•They contain a hinged jib. In level luffing crane, the hook remains at the
same level. While they move the jib up and down. It is usually used for
unloading and loading the ships with containers.
•Careful movements are required while moving the jibs near the ground
level.
96

97. Truck Mounted Crane
•These types of cranes are mounted on a rubber tire truck and provide
excellent mobility. The outriggers will extend vertically or horizontally and
are used to stabilize and level the crane when it is hoisting a load of
materials.
•It is in that types of cranes which have one engine. It means that same
engine is used for undercarriage and as well as for crane.
•Its main advantage is that it can travel on highways itself, which makes it
easy and less expensive. It does not need any other vehicles to transport it.
•They can be rotated up to 180 degrees. But some of them rotate up to 360
degrees but these are more expensive.
97

98. Tower Crane
•A tower crane is considered to be a modern form of a balance crane.
•Usually, they are fixed to the ground in concrete or attached to the side of
structures-give the best of height and lifting capabilities.
•They can left load up to 20 tons approximately and work up to 256 feet
height approximately. The operators of the crane mostly use radio and hand
signals as a medium for communication to hook or unhook the load.
•Tower cranes have their jib extending horizontally from the mast, which
itself rests on a concrete base.
•A luffing jib is able to move up and down, while the fixed jib has an
operating dolly that moves materials horizontally. The engine (slewing unit)
that controls the rotation of the crane sits on the top of the mast.
98
tower cranes are built along with
the building, growing alongside it;
With its height, ability to lift heavy
materials, and various features,
tower cranes are an essential tool
when constructing a tall building.

99. Overhead Crane
These types of cranes are also known as suspended cranes.
They are generally used in a factory and some are able to lift very
heavy loads.
The hoist of the crane is set on a trolley that will move in one direction
along a beam, sometimes two beams.
They move at angles to the direction along the elevated or ground
level tracks.
The tracks are usually mounted along the side of an assembly area.
99

100. Loader Crane
This is a hydraulically powered crane that has an articulated arm that is fitted
to a trailer.
A loader crane is used to load equipment onto a trailer. The crane can be
folded into numerous sections and will fit into small spaces when not in
use.
The crane can be easily transported because of its capabilities to be folded.
100

101. Crawler crane
•Crawler crane moves it self with the help of tracks which is also called
crawlers.
•Their main advantage is that it can move mostly on any surface of the earth
it can even move on soft soils due to its crawlers. Because it transfers its
load to a great area. That’s why it can be used at unprepared sites without
worrying about anything.
•And their main disadvantages is that it is very heavy and move on tracks.
That’s why it can not be moved easily from one site to another and will cost
more money.
101

102. Stacker Crane
•Stacker cranes are automated machines
with a forklift-like mechanism and are
primarily designed for warehouse
storage.
•Typically, stacker cranes are used in
places with special working conditions,
like extremely cold temperatures,
making it unnecessary for a human
worker to endure extreme working
conditions.
102

103. Aerial Cranes
•These types of cranes are also called Sky Cranes. They look like helicopters
and used to carry large loads. They are used mostly in that places where
reaching by land is difficult. And as all of you know that Helicopters fly
which means they are capable of reaching any place.
•They usually lift loads to high rise buildings. They can lift anything in their
capacity from boats, cars to pre-made swimming pools. They can also be
used for rescue purposes in disaster.
103

104. Bridge/Overhead Crane
The bridge crane, also known as an overhead crane, are typically found
in industrial environments. Its name comes from the fact that it
resembles a bridge supported by twosteel beamsthat straddle the
workload, with the hoist (lifting mechanism) traveling along the
bridge part of the crane.
104

105. Hammerhead Crane
•Hammerhead cranes are some of the
most commonly used in construction
projects. This crane has a horizontal,
swiveling lever resting on a fixed tower.
The trolley is held in the forward part of
the arm and is counterbalanced with the
part of the arm that extends backward.
•Hammerhead cranes also offer a feature
known as racking, which allows the
trolley to move forward and back
horizontally along the crane arm. These
cranes can be extremely heavy and are
assembled on the job site.
105

106. Bulk-handling Crane
•Bulk-handling cranes are used to carry large volumes of heavy materials,
like coal or minerals. Instead of a hook at the end, bulk-handling cranes
have a specialized hook that utilizes a grabbing mechanism and a bucket to
grab, hold, and lift materials.
106

107. Floating Crane
•Also known as a crane vessel or crane ship, crane vessel or floating crane-
are used for projects at sea, such as ports or oil rigs.
•As of today, there are several types of floating cranes as well, such as the
sheerleg and semi-submersible.
•It is mostly used in offshore construction and they are specialized in the
lifting of heavy loads. They can also be used to load or unload ships or lift
sunken ships from the water. They are fixed and therefore can not be
rotated. They have a large capacity of about 9000 tons.
107