Marine Construction2017

Philippe BoissinotTrimble Marine Construction

Momchil MinchevBulgaran Geoinformation Company

Types of Projects Port Construction

– Dredging support – hydrographic surveys– Onboard Dredgers– Placement of structures - wharfs

Coastal Engineering– Breakwaters, ocean/sea outfalls

Piling – Vertical and raked

Offshore Oil and Gas structures – Oil Rig Moves, Pipe lay

Port Construction

Survey Hydrographic Software: HYDROpro

– Pre and post dredge surveys Colour binning

– Easy data transfer to post processing packages Surface modelling Volumes Channel design

– Supports wide range of sensors and positioning systems

– Position from DGPS or RTK If DGPS then use tide gauges If RTK – must have a geoid model or

site calibration

Site Calibration for Geoids

Dredgers Cutter Suction Trailing hopper Clamshell with crane Hydraulic excavator

Dredge - RTK System Trailing Hopper dredger’s draft changes during

operation Use RTK heights and reduced levels – no tide gauge Heading is required for determining offset positions Equipment:

– Trimble RTK + GPS heading (centimetre position & heading)

– Tilt sensor for dredge arm angle (decimetre on head)– HYDROpro Dredge for sensor integration and guidance

Variable but measurable

Constant offset

Dredge - DGPS system Non hopper dredgers have constant draft DGPS is cost effective but lower precision than RTK Heights and depths are relative to water level Equipment:

– Trimble DGPS receivers (sub metre position/heading)– Pressure based dredge head depth sensor (Bubbler)– Radio tide gauge– HYDROpro Dredge

Spud pole

Operator Interface Clearly indicates Cut/Fill at

the dredge head– Text display shows

numeric Cut/Fill– Areas to dredge easily

identified by colour on plan view map

Profile views from dredge head perspective– Dredge head depth– Design, dredged and pre

dredge surfaces viewable Monitors coverage

Benefits Confidence

– Operator has real time guidance– Accurate, reliable dredge depth– Minimize over-dredge and rework– Provide daily “dredged surface” CAD updates

for client Cost savings

– Reduced survey cost– Minimize over-dredge, maximize profit– Faster project completion

Design and Progress Reporting– HYDROpro software handles with ease

Hydro survey and Import survey surface Channel design – cross sections, long sections Export design channel or surface to dredgers Volume calculations Redesign sections as required

Coastal Engineering

Sea-wall / breakwater Construction Rock Dumping Barge

– DGPS submeter positioning– Heading is essential– HYDROpro software to position and align barge

Locate a crane load in all 3 dimensions - how?

Challenges are:– Placing large foundation blocks

in a regular pattern underwater– Zero visibility– Precisely excavating with a

clamshell bucket– Guiding the load so an unskilled

operator can place and record

Horizontal Positioning - Crane Boom tip mounted GPS (GPS1)–

gives horizontal positioning – Use RTK precision if vertical

positioning also needed– Single antenna gives guidance

related to North, e.g. “Go 4.1𝒎𝒎at 45° to North”

Boom

GPS 1

GPS 2 -heading

Add a cabin mounted GPS antenna (GPS2) for heading and orientation– The extra antenna assists operator guidance with

HYDROpro as positioning is now in terms of the crane reference frame (‘go left’, ‘go forward’)

Gimbal mounting the antenna

Keeps antenna horizontal and directly above the load

Make the mounting on site

Vertical Positioning Cable Pay-out device The rotary sensor is

mounted on the boom tip pulley

Its calibrated onsite Accurately measures

cable in and out

Depth measurement – Cable Pay-out

Boom

GPS 1

GPS 2 -heading

Cab Display

Encoder Installation –make on site

Cable Out sensor

In cab mounting PC

– Large LCD screen– Runs on 12-24 V DC

Sea-wall and Land Reclamation

Example: Brisbane, Australia

Port Expansion projects

Laying seabed Geotextile from barge

Sea-wall and Land Reclamation

Using HYDROpro software

Sea-wall and Land Reclamation HYDROpro for marine

rock dumping Trimble GCS900 used on

excavators Terramodel for design

and during construction phase

Marine Piling

Conventional Trimble SPS930 for setting out piles Direct Reflex to reflectorless targets (sides of piles) Use this technology for short ranges, and vertical piles

Place more piles and structures faster– Can work day and night, in fog– Real time positioning, no delays

Empower your workforce– Barge operator has total control

Do it in a safer manner– No personnel in dangerous positions

Use proven technologies – Used worldwide on piers, bridges and wharves– Used for vertical and raked (battered) pile placement

Why use GPS?

Provides accurate position and guidance information for:– Jack-up piling rigs– Barge mounted piling rigs

Uses RTK GPS technology– centimeter precision for 3D position– Real time– Corrected for tide and water level changes– Accurate heading

Solutions developed with marine construction companies since 1995

RTK GPS Pile Positioning System

The Benefits of a GPS System Offers many benefits over

other techniques– Optical– Laser– EDM

Cost savings– 24 hour operation– Barge Operator has direct

information – Shorter placement time per

pile due to direct operator guidance Direct operator guidance

Operator interface Visual displays provide information

on pile positioning such as:

– Current position– Distance to go to location– Pile rake & heading - current

and required– Distances from obstacles– QC information– Barge heading

Piling for Windmill parks Many windmills are

being built offshore Therefore, piles are

used as the base structure for each windmill

Offshore Oil and Gas

Construction of Oil Platforms Positioning of above-water structures,

seabed structures and in-the-water columns Nothing is static Satellite based GNSS corrections such as

SeastarTM. Now able to achieve 30 𝒄𝒄𝒎𝒎globally

Precise Positioning underwater Long Baseline array: Relative calibration,

followed by absolute calibration Good for horizontal positioning. Choose the

acoustic frequency– Higher freq, shorter range, greater accuracy

Transponders

Deep Structure Positioning an array of transponders (EHF, 5 𝒄𝒄𝒎𝒎) two transceivers at the ends of the pipe guidance

What is missing ?

Subsea devices for imagery (SSS, Interferomtric sonars)

Multibeam and singlebeam echosounders USBL/LBL, acoustic postionning Motion sensors SVP and CTD Acquisition and post processing software Subsea Camera ROV

Trimble is not a wizard!

Thank you!