TerraTech Consulting Ltd

Sub-bases for Sports Pitches

Design Methodology

Engineered sub-base

TerraTech Consulting Ltd has developed a comprehensive design methodology for synthetic third generation (3G) sports pitches.

  • Site selection
  • Topographical survey
  • Ground investigation
  • Foundation design
  • Commissioning

 

"Case Studies of Synthetic Pitches in Ireland" (CERI 2026) details two case studies: Holy Trinity College, Cookstown, Co. Tyrone, and Ballyfin National School, Co. Laois. These projects demonstrate the geotechnical assessment of near-surface soils, subsoil drainage conditions, and subgrade bearing capacity required to support multi-layer synthetic turf systems.

Holy Trinity College, Cookstown, Co. Tyrone (2025)

Full-size GAA Pitch

A 1200mm thick granular base was constructed over soft glacial sub-grade with CBRs of 2% and an undrained shear strength of 40kPa. The granular base is reinforced with two layers of WG80 woven geotextile which act as a separator and a reinforcing membrane.

Pitch Construction

  • Drainage
  • Geotextiles
  • Granular base

 

 

Ballyfin National School, Co. Laois (2026)

Pitch size: 45m length, 29m width

This site is underlain by competent Devonian Sandstone Till with verified CBR values consistently exceeding 5%. Ground conditions permitted a simplified pavement design using the Giroud and Han (2004) method without structural geogrid reinforcement. A 250mm granular foundation proved sufficient to meet performance requirements.

Pitch Construction

  • Initial DCP Testing

  • FWD Testing
  • Installation of blinding, shockpad and carpet