Civil Infrastructure

Project Title: 

Luas Cross City extension, Geospatial management | Murphy Geospatial

Location:

Dublin City

Client: 

Sisk Steconfer JV

Business Sectors: 

Civil Infrastructure

Services (Technical Disciplines):

• Survey
• Engineering
• Geospatial Data Collection

Project Objectives/ Outcomes:

This critical piece of urban infrastructure links up two existing light rail corridors in Dublin city centre comprising of 5.9km of new track, 13 new stops and associated works. Murphy Geospatial were the Geospatial Managers for the entire project working in partnership with the Sisk Steconfer JV. Geospatial certainty throughout the life cycle of the project, managed reliably by an experienced Murphy Geospatial team, was a key reason this project was delivered on time and on budget.

Our Role: 

Murphy Geospatial played a critical role in the success of the project, delivering surveying and engineering services during the design and construction phase. Our Head of Digital Construction, Michael Durnin, acted as Chief Surveyor with SS JV and oversaw every aspect of survey and geospatial data collection including establishing the control network, all setting out works, deformation monitoring and subsurface mapping.

Early engagement and collaboration during the pre-construction phase was the key to success. Murphy Geospatial strong and trusted relationship with the Sisk Group over years of working together was also instrumental.

Technical sensor driven solutions were used to automate the data capture process. Compared to more traditional methods this reduced risk, cost and optimised efficiency. Data management workflows were also integrated into the project which increased on-site efficiency and productivity.

Challenges during the project included TII’s construction specifications. 1mm relative change over 1m of track was an extremely tight tolerance for rail construction. 1:60,000 linear accuracy and 5√k for control are both very difficult to achieve in a heavily urbanised environment and in phased construction works.

The specification also included localised variables for paving under tight constraints where real-time decisions against design were made by the setting out teams.

Despite facing tight constraints and the challenges of such a large and complex site, the survey works were completed to a high standard in line with the specification.

Key Construction Statistics

• Total single line track: 13.4km
• Total weight of the tracks: 1,520 tonnes
• On street, concrete track bed and shoulders poured: 13,600m3
• Total ducting and pipes under the surface: 178,000m
• Projected total man hours to complete SSJV works: 3 million hours

Geoscience Ireland Contact:

Dave Graham (dgraham@murphygs.ie)

Project Title: 

A14 Cambridge to Huntingdon Improvement Scheme | Causeway Geotech

Date:

May to November 2016; additional supplementary phases completed in 2017, 2018, 2019 and 2020

Location:

Cambridge, England

Client: 

A14 Integrated Delivery Team (Balfour Beatty / Costain / Skanska JV)

Business Sectors: 

Civil Infrastructure

Services (Technical Disciplines):

Ground investigation / Geotechnical and Geoenvironmental Engineering

Project Objectives/ Outcomes:

Causeway Geotech were appointed by A14IDT to carry out the Ground Investigation for the proposed bypass road between Huntingdon and Cambridge. The scheme covers a total of 35km and the investigation was scoped to provide assessment of geo-environmental conditions to assist the design and construction of the highway and associated structures.

The investigation was successfully completed under the supervision of a Chartered Engineer and five Site Engineers from Causeway Geotech working closely with the Client’s Representative and Client alike.

Our Role: 

Causeway Geotech acted as the main ground investigation contractor for the scheme.

The scope of works included:

• 158 Cable Percussion boreholes to a maximum depth of 20m
• 83 Rotary cored holes using Geobor-S techniques to a maximum depth of 55m
• 43 Dynamic sampling boreholes to a maximum depth of 10m
• 3 Light Percussion boreholes with rotary follow on utilising a slope climbing rig to a maximum depth of 25m
• Static Cone Penetration Testing (CPTs) at 4 locations
• 87 Trial pits with a mechanical excavator to 4.5m depth.
• Insitu testing including SPTs, Dynamic Cone Penetrometer, Plate Loading Tests
• Monitoring installations including standpipes, gas monitor wells, piezometers and triple vibrating wire piezometers (VWPs) which were installed using cement bentonite grout.
• Site monitoring of water levels and gas concentrations, PID headspace readings, interface probe readings and VWP downloads.
• Specialist surveys including Laser Induced Fluoresence (LIF) and sampling for suspected anthrax.

The works were carried out across a variety of terrain including agricultural land, parkland, river banks, existing structures, carparks, existing road verges and carriageways under control of Traffic Management on day and night shift.

Geoscience Ireland Contact:

Darren O’Mahony (Darren.omahony@causewaygeotech.com)

Project Title: 

Eccles Heath Structure Survey | Murphy Geospatial

Location:

United Kingdom

Client: 

J. Murphy and Sons

Business Sectors: 

Civil Infrastructure

Services (Technical Disciplines):

• Digital Construction
• Rail Surveys
• Topographical Surveys

Project Objectives/ Outcomes:

Eccles Heath Bridge (ETN 1613) is a three-span overbridge (7.5T) carrying a single lane road over the up and down lines of ETN Ely to Norwich (non-electrified route). Following an incident in December 2017, where a vehicle collided with the existing parapets, the bridge has been closed to road traffic. Installation of new compliant parapets was not feasible, thus, full superstructure replacement was required The initial works were to carry out a track alignment and road survey for the bridge. This was subsequently extended to include a topographical survey of an adjacent field to be used as a site compound. Finally, we were commissioned to locate and mark the location of buried services within the field in order to facilitate the planning of heavy lifting works.

Our Role: 

Murphy Geospatial have a long experience working in the rail environment and are fully conversant in Network Rail Standards and Procedures.  The brief for these works was governed by strict adherence to these requirements, together with the requirement to complete the survey within the restricted time access available.  A team of rail survey specialists in topographical surveys, laser scanning and sub-surface utility surveyors, together with our 3D modellers was designated to this project.

Process

Whilst the Network Rail standards are clearly defined, we worked closely with the client to determine the exact deliverables and the most practical and cost-efficient format.

Given the restrictions on access it was important to plan the right blend of experienced personnel with the latest equipment sufficient to complete the works with contingency available to allow for possible delays.

The works were executed according to plan; The following items were issued:

Detailed survey report to NR/L2/TRK/3100 standard to include witness diagrams, schedule of control, traverse and level diagrams and accuracy obtained.
Digital data a) Registered point cloud data in scanworld, combined and unified database outputs (*.IMP files), and *.POD files. b) 3D Wire frame model (Microstation .dgn) – topographical data extraction from point cloud including utilities tracing and plotting in 3D.

Initial expectations were met and the client subsequently commissioned further works on the project.

Geoscience Ireland Contact:

Dave Graham (dgraham@murphysurveys.ie)

Project Title: 

Innovative Concrete to Achieve Special Finish | Roadstone

Location:

Dublin

Client: 

Dublin City University

Business Sectors: 

Civil Infrastructure

Services (Technical Disciplines):

Design of architectural concrete mix.

Project Objectives/ Outcomes:

Opened in late 2018 the open auditorium of DCU’s “U” Building forms the center piece of this state-of-the-art student facility. The design of the auditorium required that all primary structural elements be exposed with a ‘special finish’ to EN 13670:2009 Execution of concrete structures specified for the concrete elements. This special finish placed numerous requirements on the concrete beyond what would be typically expected including: 

• A light colour 
• Consistency of colour 
• Minimal blemishes 
• “DCU SU” embossed lettering 

To aid in achieving uniformity of colour and finish Roadstone tested the consistency of each load of concrete prior to dispatch to site and maintained close communication with site engineers for the duration of the project.  

Completed in separate pours over a six-month period, over 20 loads of architectural concrete were supplied to DCU Hub. As well as meeting the demands of an architectural finish the concrete also met structural and durability requirements. 

Our Role: 

An architectural concrete was required to achieve the special finish and the specific design team requirements for the concrete used in the central auditorium.  

The design of the architectural concrete mix required a slightly different approach to that of conventional concrete mixes, with particular attention placed on the mix proportions of the cements and aggregates. A relatively high cement content was required with the proportion of sand in the mix not being twice that of the cement content.

In addition, a single sized 20mm coarse aggregate was used. Designing the mix in this manner resulted in a gap graded mix and allowed for the finer materials in the mix to migrate to the formwork surface following placement and compaction, producing a high-quality finish with minimal blemishes. 

Sample panels were poured to assess the performance of the architectural concrete mix and the workmanship required to achieve a high-quality finish prior to pours commencing. This allowed for an assessment of a variety of criteria and their impact on the quality of the concrete finish. 

This aided the concrete contractor, site engineers and Roadstone concrete technologists in understanding the impact of workmanship and the concrete mix on the concrete finish. The criteria included: 

• Type of formwork 
• Grout-tight formwork joints 
• The release agent and its application 
• The method and rate of placement of the concrete 
• The suitability and consistency of the concrete mix 
• The compaction plan 
• The most suitable time at which to strike the formwork

Geoscience Ireland Contact:

Diarmuid McCarty (dmccarty@roadstone.ie)