Best Practices

Dennis Clausen

Director of Training

GOMACO Corporation

Considerations for Profile Paving

Stringline Installation & Maintenance Subgrade Stability and Accuracy Concrete Control & Placement Paving Basics Finishing Operations Other Considerations

Stringline Installation & Maintenance Setting & Maintaining Accurate

Stringline Recommend 25’ Surveyed Stations and Stringline Stakes,

Closer Intervals in Horizontal and Vertical Curves.

Stringline Installation & Maintenance Setting & Maintaining Accurate

Stringline Recommend 25’ Surveyed Stations and Stringline Stakes,

Closer Intervals in Horizontal and Vertical Curves. New Condition Cord, Wire, or Cable. Daily Maintenance & Checking of Stringline Elevation and

Alignment. Daily Maintenance on Stringline Tightness.

Subgrade Stability Stability of Paving Grade

Unstable Grade Causes Thickness Control Problems if Haul Trucks are Placing Concrete on Grade.

Possible Profile Problems if Subgrade continues to Move.

Subgrade Stability Stability of Paving Grade

Unstable Grade Causes Thickness Control Problems if Haul Trucks are Placing Concrete on Grade.

Possible Profile Problems if Subgrade continues to Move. Stability of Track Line

Track Line Failure may Occur Causing Profile Deviations.

Subgrade Stability Stability of Paving Grade

Unstable Grade Causes Thickness Control Problems if Haul Trucks are Placing Concrete on Grade.

Possible Profile Problems if Subgrade continues to Move. Stability of Track Line

Track Line Failure may Occur Causing Profile Deviations. Stability of Haul Road

Safety Important because of Possible Delays in Concrete

Delivery. In Extreme Cases may Affect Paver Track Line Grade.

Subgrade Accuracy

Accuracy of Paving Grade & Trackline.

Fewer Changes in Elevation by the Paver, the higher

probability of good profiles. Accurate Grade Elevation Makes Concrete

• Placement More Consistent.

Placing With Transit Mix

Considerations if Transit Mix Must be Used Plant Should be Central Mix if Possible Mixer should be Designed as Paving Mixer Chutes Must be Kept Clean Control of Clean-out Water Must be Monitored Position and Placement of the Truck Mixer is

Critical

Placing Central Mix Concrete

Positive Factors of Central Mix Placement: Most Efficient Mixing System, helping make a more consistent mix. Faster to Unload End Dump & Bottom Dump Trucks. Use of Placers & Placer Spreaders May:

Allow the Paver to Move at a Consistent Rate of Speed. Allow the Paver to Operate with a Consistent Head of Concrete. Eliminate Large Piles of Concrete, which vary loading on the paver. Require Close Monitoring if Concrete Slump varies or if Subgrade is no

Accurate

Paving Basics

Paving Basics

Paving Form Must be Clean Designed for the Width to be Paved Maintained According to the Manufacturers

Recommendations Assembled and Adjusted to the Manufacturers

Recommendations Operated by Trained Personnel Operated by Motivated Personnel Paving Crew Must Operate as a Team Paving Team must have Pride in Their work

For A Paver to Perform at Optimum it Must be:

Extrusion Type Paving Form

Must be Properly Adjusted for Good Paving Results. Establish a Set-Up Procedure and Follow it Religiously. Pan Should be Straight & True, Left to Right & Front to

Rear. For Good Profile Results, Pan Should be Set Parallel to

the Stringline Front to Rear. Check the Profile Pan for Accurate Setting after:

– Width Changes – Moving the Machine

Replace or Repair Damaged or Worn Parts When Necessary.

Finish Procedures

Good products

Finish Procedures

Good products Check product dimensions

Finish Procedures

Good products Check product dimensions Problem areas

Finish Procedures

Good products Check product dimensions Problem areas Start and finish headers

GSI The Contractor’s Tool Before Paving

Check smoothness of the sub-grade Check smoothness of the stringline setup Calculate yield of the paving materials based on sub-grade and stringline setup Pin point areas of cuts and fills in the sub-grade

Stringline Sensor

GSI Tools Analysis Software

Sub base analysis for McCarthy Improvement in South Carolina

With the GSI you can collect the same sub grade measurements

every 2 inches

GRADE CUT/FILL DETAILS STATION REFERENCE DEVIATION HEIGHT ROW INTERVAL RESOLUTION – 2”, 6”, 1’, 12’, 25’, 50’,

100’, ect. COLOR CODED CUT AND FILL PARAMETERS – BLUE = FILL – RED = CUT

SLAB VOLUME NOMINAL SLAB VOLUME VOLUME DEVIATION THEORETICAL VOLUME (NOMINAL + DEVIATION)

REPORT JOB INFORMATION TRACE DETAILS SLAB VOLUME PROJECT PARAMETERS GRADE CUT/FILL SUMMARY

USER ADDED GRAPHS KNOWN FILE FORMAT FOR SHARING INFORMATION AND PRINTING

– (*.HTML FILE USES INTERNET EXPLORER FOR VIEWING AND PRINTING)

GSI The Contractor’s Tool During paving process

Provide paving crew immediate smoothness readings right out of the paver – Corrections may be made to the pavement

surface while concrete is still in plastic condition – Adjustments can be made to paving operation

before thousands of feet have been paved Separate machine can be backed over the repaired surface to take readings again

Check Profile of Poured Concrete Behind Paver

Check Profile of Poured Concrete Behind Paver

Check Profile of Poured Concrete Behind Paver

Check Profile of Poured Concrete Behind Paver

View 2 Traces

View Report in PI or IRI Format

3D Stringless Control System for Curb & Gutter, Trimming & Concrete Paving

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What is Stringless 3D? A 3D Machine Control system that simplifies jobsite logistics, reduces costs and improves quality and safety

Removes stringlines and pins from the jobsite

Removes install, maintenance & removal costs

Increases working safety, especially at night

Puts the 3D job design directly onto the machine

Eliminates setting-out errors and stringline influences

No waiting for setting-out before production

No dependency on setting-out – work wherever you have 3D data

Increases productivity, quality and performance bonuses

Controls height, slope (and steer) of machines

Delivers a precisely-constructed product

Optimises amount of new material needed

Reduces over-trimming, overpouring

Improves concrete yields and material cost savings

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Working with Stringline…

Inspect design – calculate setting-out lists for each lane

Setup a theodolite, survey each hub or pin position with total station (or GPS if accuracy isn’t important!)

Hammer (or drill) in each pin, minimum 1 line for each lane of concrete/asphalt

Check pin alignment & adjust if required

Survey and set stringline height on each pin (min. 2 men)

Install & tension clamps and stringlines

“Eyeball” & adjust stringlines before paving

Move machine into position, set sensors to stringline

Check machine position relative to stringlines

Start Production, monitor machine position

Ensure (or hope!) nothing disturbs or damages stringlines during paving/milling…

Reference Point

Walk left 5ft! Walk right 1ft!

Up a bit! Down a bit!

STOP!

Reference Point

Mainline Slipform Paving & Fine-Grade Trimming with Stringless 3D

Click to return to Main Menu

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Why go “Stringless”? Could your paving projects benefit from…

…no marking-out and drilling to setup pins and guidewires?

…easier paving in “zero clearance” situations, e.g. bridge decks, urban streets, railway cuttings, tunnels, narrow motorway lanes?

…no special access/safety equipment to pave in tunnels?

…no pre-production planning – just arrive, pave anywhere, any time?

…no human error from stringline setup?

…no inaccuracy of “field model” compared to original “office design”?

…lower material costs, improved concrete yield (less waste)?

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Why go “Stringless”? Because stringlines… … are expensive, time-consuming and error-prone to install

… can be easily damaged during paving

… can be easily misaligned

… can be a significant site safety hazard

… interfere with site logistics, increase concrete delivery

time, haulage costs, and reduce productivity.

… require pre-production planning & increase survey effort/cost

… don’t always “model” the designed surface accurately

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What is 3D?

A 3D Machine Control system simplifying slipform jobsite logistics, reducing cost, improving quality and productivity

Specifically designed for mainline (slab) pavers & trimmers

The result of 16 years worldwide experience in 3D slipforming

Developed in close cooperation with GOMACO

Eliminates stringlines (“stringless control”)

Controls paver elevation, steer, slope and draft

Constructs directly from the 3D plans

Removes need for stringline set-out crew

Minimises pre-production planning and preparation

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Stringless System for Gomaco Trimmers System Components

Machine Computer

Radios

Slope Sensor

Prism

Theodolite #1 (Guidance)

Theodolite #2 (As-builts & Leapfrog)

Reference Point

Reference Point

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Stringless System for Gomaco Placer/Spreaders System Components

Machine Computer

Radio

Slope Sensor

GPS or Prism

GPS Reference Station

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Stringless System for Gomaco Pavers System Components

Machine Computer

Radios

Slope Sensors

Prism

TPS #1 (Guidance)

TPS #2 (Guidance)

TPS #3 (As-builts & Leapfrog)

Reference Point

Reference Point

Prism

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Faster, more accurate trimming… Optimal subgrade saves concrete and improves rideability

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Smoother airfield paving… Increases runway life, reduces undercarriage & tyre wear

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Smoother road paving… Increases road life, reduces vehicle wear & passenger fatigue

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Practical Issues… In the field!

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Practical Issues Checking concrete (or subgrade) level and position

The third theodolite together with a prism measures the surface “as-built” behind the machine

Errors (and adjustments) shown on theodolite

Report stored on 3D computer

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Practical Issues Adjusting the Machine

If the level needs adjusting…

…just like stringline control we can adjust all leg heights, and draft independently, without stopping paving

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Practical Issues Adjusting the Machine

If position needs adjusting…

…just like stringline control we can adjust position at front and rear independently, without stopping paving

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Practical Issues Moving the Theodolites (‘Leapfrogging’)

Maximum Range Theodolite-to-Paver is <= 200m (*depends on conditions)

We don’t want to stop the paver for too long!

Before maximum range is reached, move 3rd Theodolite to new position & setup (Position & Orientation Fix).

Press ‘Swap Theodolite’ on computer

System switches control from #2 (or #1) to #3 Theodolite automatically

Move ‘old’ Theodolite to new position, setup and repeat procedure

Ensure enough Reference Points visible for Setup (Position & Orientation Fix)

* - temperature, humidity, air quality

Questions?

Dennis Clausen

Director of Training

GOMACO Corporation