03 HeavyTransport 2Day UK 50 Pages.key

March 19, 2018 | Author: Javier Páez | Category: Crane (Machine), Suspension (Vehicle), Steering, Trailer (Vehicle), Elevator
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Paquete de estudio para transporte e izaje...

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1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Heavy Transport with hydraulic platform trailers

Jan.2010

1

www.heavyliftspecialist.com

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Difference between Platform trailers and standard flatbed trailers

Hydraulic cilinder

Spring system

Swing arm

2. Standard flatbed trailer

1. Platformtrailer –

– – – –



Spring function by means of a hydraulic suspension with nitrogen accumulators A certain load creates a certain oil pressure in the system Every axle pushes with the same load on the road surface The hydraulic suspension is at the same time a built in jacking system Steering is via a drawbar that activates hydraulic steering cylinders, which in turn activate each axle with a certain steering angle The steering function can also be activated with a separate power pack

– – – – –

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Spring function by means of steel springs or swing arms A certain load on the trailer pushes the springs in Every axle takes a load depending on the pressure on the spring system No built in jacking system Steering always by means of tractor unit

2

3.USA Dollie transport example

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

2. Manufacturer has adapted his Platform trailer by leaving out some axlelines 1. To meet the USA Higway load-limit requirements, dollie systems are often used 3

www.heavyliftspecialist.com

3.Principle of the hydraulic platform trailer

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

1. Biggest advantage is the absorbtion of uneveness in the road 2. Large payload per axle www.heavyliftspecialist.com

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3.Principle of the hydraulic platform trailer

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

1. By means of hydraulics the load per axle is distributed evenly 2. We can create a 3- or a 4point suspension system

SADDLE PROJECTS OVER SIDE OF TRAILER TO FACILITATE LOADING/UNLOADING OF CARGO SUPPORTS FROM WHICH CARGO CAN BE PICKED UP OR PLACED DOWN BY MEANS OF TRAILERS HYDRAULIC SUSPENSION

6200 8000

5

www.heavyliftspecialist.com

3.Principle of the hydraulic platform trailer SPMT=Self Propelled Modular Transporter

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

Conventional Nicolas Platform trailer

ADVANTAGES: • More payload per axleline • Hydraulic axle leveling • Built in jacking system • Hydraulic steering system • Standard modules can be coupled together to large units www.heavyliftspecialist.com

DISADVANTAGES: • More expensive trailer • More maintenance • Lower driving speed • Need a special permit in most cases 6

3.Principle of the hydraulic platform trailer

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

1. Max. stroke of hydraulic cylinder is approx. 600-700 mm 2. Oneveness in the road must stay within this max. stroke 3. Due to hydraulic piping between all suspension cylinders, oil will flow between axle suspension cylinders and equalize unevenesses in the road 7

www.heavyliftspecialist.com

3.Capacity of Conventional Platform trailers (pulled by heavy duty tractor unit)

6 axleline Platformtrailer

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

single wide ( 2 File) 1200+300 1800 3000

1500

Specification of Conventional Platform trailers 1. Double tires (8 tires = one axleline 3 m wide) 2. Net average payload approx. 25-30 Ton (3 m wide) = 3,125 –3,75 ton / tire 3. Average own weight per axleline approx. 3-5 ton depending on manufacturer 4. Well known brands are: Goldhofer, Scheuerle, Cometto and Nicolas 5. The trailers can be bought in modular units of 3, 4, 5, 6, and 8 lines of 3-3,6 m wide 6. The axleline distance varies from approx. 1.40 – 1,80 m depending on the application and manufacturer (In Europe mostly 1,5 m) 7. Due to the modular format one can compose trailers with upto 36 axlellines 8. There are also trailers that can be split lengthwise, thereby creating a trailer with 3 files (1 ! wide) 9. Steering is by means of steering rods and hydraulic cylinders 10. The trailer cannot turn on the spot www.heavyliftspecialist.com

1 1/2 wide ( 3 File)

4700 double wide ( 4 File)

3200 6200 There are now also Self Propelled Conventional Platform Trailers 8

3.Capacity of Conventional Platform trailers

1. 2.

3. 4. 5.

What trailer combination is needed for a pressure vessel of 50 m long, a diam. of 7.5 m and a weight of 466 Ton, with equal load division over the two transport saddles One could select a single 12 axleline trailer with turntable and at the rear on a double wide 6 axleline trailer with turntable. Due to the large diameter of the column one has coupled the rear trailer as a double wide unit to ensure sufficient stability. Net payload approx.12 x 25 = 300 ton per trailer: total approx. 600 ton payload A single MAN heavy duty tractor unit is used for propulsion (on a horizontal level this is just sufficient) Max. pulling force of MAN with GVW of 32 ton = +0,85 x 32 = 27.2 Ton Friction is approx. 2-3% of Gross Vehicle weight: 466 Ton + 96 + 32 ton = 594 ton x 0.03 =17.82 Ton www.heavyliftspecialist.com

3.Capacity of Conventional Platform trailers

1. 2. 3.

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

9

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

What trailer combination is needed for transport of a reactor of 35 m long, a diam. of 5.5 m and a weight of 810 Ton, supported by 4 steel transport saddles equally spread over 20 m length of the reactor We selected here a set of double wide 18 axlelines of Self Propelled Conventional Goldhofer Platform trailers (Net payload approx. 2 x18 x 25 = 900 Ton). Notice the 4 transport saddles with steel support beams in order to be able to load/unload the column without the help of cranes www.heavyliftspecialist.com

10

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Capacity of SPMT’s

Specification of Self Propelled Modular Transporters (SPMT’s)

Basic unit 8400

4 x 6 axleline SPMT’s composed to one unit with 2 powerpacks

Single SPMT

2430 Double SPMT

Net payload of a 6 axleline unit is approx. 180 ton

1. Single tires (4 tires = one axleline = 2,43 m wide) 2. Net average payload approx. 30-35 Ton (2,43 m wide) = 7,5 – 8,75 ton / tire 3. Average own weight per axleline approx. 3,75-4,5 ton depending on manufacturer 4. Well known brands are: Scheuerle, Kamag, Nicolas, Cometto and Goldhofer 5. The trailers can be bought in Modular units of 4 and 6 axlelines of 2,43 m wide 6. The axleline distance is in most cases 1.40 m 7. Because of the modular format one can compose trailer configurations of almost unlimited size and payloads. 8. There are also trailers that can be split lengthwise, hereby creating a more stable unit or 3 file wide unit ( 1 ! wide) 9. Because of the computer steering mode of each individual axle one can place each trailer unit apart from each other under the load and still drive as one trailer combination 10. The trailer can drive sideways, crawl or turn on the spot (Carousel mode) 11

www.heavyliftspecialist.com

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Capacity of SPMT’s

1.

Transport of 1050 Tons heavy reactors for the Shell Pearl Project in Qatar on 2x18 lines + 1x12 lines

2.

SPMT’s, individually placed under the transport frame Total 48 lines SPMT’s per reactor = Net Capacity : approx. 48 x 30 = 1440 Ton www.heavyliftspecialist.com

12

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Capacity of SPMT’s

1. 2. 3. 4.

What trailer configuration is suitable for a 495 tons reactor of 4,8 m diam. and a length of 28 m with only two steel transport saddles spaced at 17 m from each other. For the transport of this 495 Tons Reactor we used 2 x 20 lines Scheuerle SPMT’s with a net payload of 1200 ton, hereby limiting the load per tire to 4.22 Ts/tire Steel beams under the transport saddles enable loading and unloading without the need for cranes The first axleline is pulled up in order to roll-off easier from the barge and negotiate turns www.heavyliftspecialist.com

13

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability of Trailers 1. How do we avoid tipping over of a transport combination? 2. Watch the location of CoG of load and traler in relation to the tipping lines and level the trailer in time

TRAILER STABILITY STABLE SITUATION TRAILER ON HORIZONTAL ROAD IDEAL SITUATION

MORE LOAD ON LEFT AXLES DUE TO CAMBER IN ROAD TRAILER MUST BE LEVELED CoG STILL WITHIN TIPPING LINES

TIPPING OF TRAILER ALL LOAD ON LEFT AXLES UNSTABLE SITUATION CoG PASSES OVER TIPPING LINE

CAMBER OF ROAD CAN BE NEGOTIATED SAFELY PROVIDED TRAILER BED IS LEVELED WITH HYDRAULIC SUSPENSION SYSTEM

www.heavyliftspecialist.com

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1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability of Trailers

1. As long as the force of the combined CoG stays within the tipping lines, there is no danger

2. At a certain road camber the force will get closer and closer to the tipping line. Because of the list of the load, the left tires will get more load and the tires will be pushed in, hereby creating even more list of the combination. 3. Make sure you do not reach this situation, as at a certain moment the pressure in the suspension is already so high that you cannot level the trailer anymore

15

www.heavyliftspecialist.com

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability of Trailers

4. At a certain moment the force will go over the tipping line and the transport combination will tip over. PAY ATTENTION: This can happen earlier then one thinks, due to dynamic effects, unaccuracy of the CoG and pushing in of the tire 5. With the hydraulic suspension system the trailer can at all times easily be adjusted to horizontal level. 6. Use a spirit level to check this frequently!!

www.heavyliftspecialist.com

16

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability: 3- and 4- points suspension Stability of the transport combination 1. Depending on the height of the CoG one selects a 3- or 4 point suspension system 2. One can group the axle suspension cylinders in 3 or 4 hydraulic groups (=points = fields) 3. These hydraulic suspension points can be created by opening or closing the right valves in the hydraulic lines 4. PAY ATTENTION: Never open or close a hydraulic valve before one knows what the effect will be

A 4 point suspension system has the best stability, compare it with a table on 3 or 4 legs 17

www.heavyliftspecialist.com

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability: 3- and 4- point suspension Advantages of a 3-point suspension system:

-

1. One can create a symmetrical or an a-symmetrical 3 point suspension system

Easier to keep it horizontal 4 8 Always an equal load distribution on the trailer and trailer frame and practically no danger of axle 1 overloading Less trouble with dynamic effects, as the load is 3 always supported on 3 points and will not wobble 2 between 2 points as in a 4 point suspension system A-symetrical 3 point suspension

Disadvantages of a 3-point suspension system:

-

Advantages of a 4-point suspension system:

-

1

3 4 point suspension 2 4

Smaller stability triangle Less suitable for high CoG’s

6

6

Bigger stability rectangle More suitable for high CoG’s

Disadvantages of a 4-point suspension system:

-

More difficult to level the trailer bed Sooner danger of overloading of axles or the trailer frame www.heavyliftspecialist.com

18

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.A Load placed on a flat bed trailer 1. The combined CoG can be calculated as follows: 25 x 5 + 10 x 1 = 35 x Y Y = 3.85 m 2. Stability angle of the load = arctg (1.15/5) =12,95o without accounting the own weight of the trailer (due to the fixed axle one takes the outer tire rim) 3. Stability angle of the combined transport combination = arctg(1.15/3.85) = 16,63o 4. Conclusion: A better stability is realized when the load is secured to the trailer and consider it as one combined transport combination

25 Ton

5m

Y 1m 10 Ton 2.3 m

Make sure that at all times the CoG stays within the tipping lines of the trailer

Weight. Load = 25 ton Weight. Trailer = 10 ton

www.heavyliftspecialist.com

19

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability of a Self Propelled Modular Transporter (SPMT) 1.

The combined CoG can be calculated as follows: 670 x 4,894 + 90 x 0,75 = 760 x Y Y = 4,40 m

2.

By drawing on scale the tipping lines (at a 3- or 4 point suspension) one can calculate the theoretical tipping angle.

! Double wide SPMT 5,33 m wide 12 axlelines ! Weight of trailer 4 x 22,5 ton = 90 Ton ! Max. stroke of hydraulic cil. = 600-700 mm ! Computer controlled steering

Tipping Lines

670 Ton

Distance to tipping line is at 3 points much smaller then at 4 points

4,40 m 750 90 Ton

Weight Load = 670 ton Weight Trailer = 90 ton

1450 www.heavyliftspecialist.com

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3.Stability of a Self Propelled Modular Transporter (SPMT double wide)

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

Tipping lines 6 6

1. By selecting an A-symmetrical 3 point suspension one increases the stability

6 6

2. The same principles also apply for conventional platform trailers 3. With a 4 points suspension system the theoretical tipping angle in this case is: arctg (1.45/4,4) = 18,23o Symmetrical 3 point suspension

4. For a 3 point suspension this is half: arctg(0,725/4,4) = 9,11o

Tipping Lines

5. For an a-symmetrical 3 point suspension it is somewhere in between: 13,67o

4

8

6. The a-symmetrical 3 point suspension system is in this case the preferred suspension system 2900 A-Symetrical 3 point suspension Make sure that at all times the CoG of the transport combination stays within the tipping lines www.heavyliftspecialist.com

3.Stability of a Self Propelled Modular Transporter (SPMT double wide) 1. One could also select a symmetrical 3 point suspension as per fig. right. The theoretical tipping angles can be calculated as below:

21

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

Tipping lines 6

6

2. The same principles also apply for conventional platform trailers 3. With a 4 points suspension system the theoretical tipping angle in this case is still: arctg (1.45/4,4) = 18,23o

Symmetrical 3 point suspension

4. For this 3 point suspension the theoretical tipping angle is: arctg(1,193/4,4) = 15,17o

1450

2900

5. For an a-symmetrical 3 point suspension it is: 13,67o

34,62o

6. This 3 point suspension system is in this case the preferred suspension system 2900

4200 Cos34,62o = X/1450 X = 1193 mm Make sure that at all times the CoG of the transport combination stays within the tipping lines

www.heavyliftspecialist.com

22

3.Stability of a Self Propelled Modular Transporter Critical (SPMT single unit)

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

Own Weight of 6 lines SPMT = 22.5 Ton 1. Column transported on 2x6 axlelines with turntables (For simplicity we ignore weight of turntables) Stability for this set of single SPMT’s can be calculated as below: 2. With a 4 point suspension system the theoretical tipping angle in this case is: arctg (0.725/4.5) = 9.15o (without taking the trailers own weight into account)

250 T

3. When the SPMT is secured to the load, the overall CoG will be lowered to: 250x4.5 + 45x0.75 = Y x 295 Y= 3.927 m 4. Theoretical Tipping angle for a 4 point suspension is now: arctg (0.725/3.927) = 10.46o

4500 3927 2x22,5 Ton

750

5. Stability in this case is critical and trailer bed must kept level at all times www.heavyliftspecialist.com

3.Conventional Platform trailer with load tipped over

1450

23

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

UNFORTUNATE MISHAP

1. This can happen due to Hydraulic Failure or 2. Not levelling the trailer when negotiating a camber in the road or making a tight turn

3. Clearly instruct operational personnel on trailer stability before they start their job

www.heavyliftspecialist.com

24

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Stability of a conventional Hydraulic Platform trailer 1. The same principles for stability apply to conventional platform trailers as well 2. Now a single trailer is in most case 3 m wide (instead of 2.45 m) and therefore have a wider stability base.

! ! ! !

Conventional Double tires In most cases 3 m wide Axle distance approx.1,5-1,80 m Max. stroke hydraulic cil. = 600 mm

3. Watch out: We only calculate the theoretical tipping angle, in which we do not yet take into account the following facts: – Inaccuracy during loading – Not exact known location of CoG of the load – Deflection of tires at the side to which the load is leaning, which only makes it worse. 4. We also did not take into account dynamic effects like speed and wind. 5. Therefore one should always level the trailer when trailer stability may become critical 1800

www.heavyliftspecialist.com

25

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Axle loads

603

4

8

1. Equal axleloads in case the Cog is

symmetrical to the hydraulic suspension points

2. We create hydraulic suspension points 3. In this case an a-symetrical 3 point suspension www.heavyliftspecialist.com

26

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

3.Calculation of axle loads axleline Individual axle

1.

We calculate the axle load by first calculating the Gross Vehicle Weight (=Total weight of combination)

Weight of Crawler = 82 T Own weight Trailer = 41 T GVW =123 T

2.

Load/axleline = GVW divided by number of axlelines

3.

Load per axle = Axleline load divided by number of axles

Load / axleline = 10.25 T Load / axle = 5.13 T Load / tire = 1.28 T Average.Groundload = 1.45 T/m2 www.heavyliftspecialist.com

3.Calculation of average groundload (This is not a scientific approach)

27

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

1. The tire of a trailer is filled with air with a pressure of approx. 12 bar (=12 kgf/cm2) 2. Due to the load on the trailer, the tire will stave in and the road gives a counter pressure of 12 bar 3. The local tire pressure on the road is therefore 12 kgf/cm2, which boils down to a pressure of 120000 kgf/m2 = 120 ton/m2 4. This is the same principle as the lady with high heels (60 kg on 2 cm2 = 30 kgf/cm2 = 300 Ton/m2) 5. We therefore calculate an average groundload at a certain distance below the road surface www.heavyliftspecialist.com

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3.Calculation of average groundload (This is not a scientific approach)

1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

2 2 2

1. In order to calculate the average groundload below the tires we draw lines under an angle of 45o. These lines represent the load spreading on the road surface 2. At a depth of approx. ! the axle distance, these lines cross each other and we assume the goundload to be at an average level at that depth below the surface 3. This is not a scientifically proven method but works relatively well in practice 4. To calculate the average groundload we take the number of axles and multiply this with the axle distance. We multiply this number again with the width of the trailer, increased with the axle distance. In that way we have calculated the projected area of the average groundload at half the axle distance below the trailer. See calculation above. www.heavyliftspecialist.com

3.Realistic ground pressure profile

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1.General Knowledge 2.Forces and Masses 3.Heavy Transport 4.Lifting with two Cranes 5.Maintenance & Inspection 6.Skidding & Jacking Techniques 7.Project Planning 8.Cost Estimate 9.Load-outs of Heavy Lifts 10.Safety & Risk Management 11.Accidents & How to avoid them

1. Realistic collapse pattern due to foundation loading

Soil Type

Load carrying capacity qc/3 (kPa)

Clay or silt Weak Relatively solid Solid

Zand Loose Relatively tight Tight

Gravel Loose Relatively tight Tight

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