EN 13286-45:2003

Overview

EN 13286-45:2003 (CEN) specifies laboratory test methods for determining the workability period of hydraulically bound mixtures made with granular materials. Workability period is the time from the end of mixing during which binder setting is nil or very low. The standard describes two complementary methods: delayed compaction (modified Proctor) and sonic propagation. Note: the sonic propagation method is not suitable for hydraulically bound mixtures with maximum particle size D ≤ 6.3 mm.

Key topics and requirements

• Scope and purpose: measure how long a hydraulically bound mixture remains workable for compaction and placement.
• Two test methods:
  • Delayed compaction method (modified Proctor, prEN 13286-2): prepare multiple samples, compact at increasing times t, measure dry bulk density r(t). The workability period Wpc is the time when r(t) drops to 98% of r(0). Two determinations per compaction time; densities must agree within 1% or a repeat is required.
  • Sonic propagation method: continuously record sound propagation duration Ds(t) through a 160 mm × 320 mm vibrocompression specimen (made per prEN 13286-52). Workability period Wps is the time when Ds(t) = K × Ds(0), where K is a bench-specific coefficient established via Annex A. Typical sonic test details: transmitter/receiver diameter ~50 ± 5 mm, contact pressure ~1.0 ± 0.1 MPa, Ds(t) recorded at least every 5 minutes, start recording within 20 minutes of mixing, continue until propagation duration is ~40% of initial or up to 24 h. Two tests at each temperature; results accepted if workability times differ by < 15%.
• Specimen preparation & environment: use fraction passing 31.5 mm sieve; store constituents and specimens at stable temperature (±1.5 °C). Record ambient temperature near specimen.
• Reporting: include mixture ID, dry bulk density, water content, procedural details, incidents, test temperature, and reported Wpc or Wps.

Practical applications and users

• Used by road materials laboratories, pavement design engineers, quality control teams, contractors, and binder manufacturers to:
  • verify mixing and compaction windows for hydraulically bound base and subbase materials;
  • optimize production scheduling and on-site handling to avoid premature setting;
  • compare workability across binder types, water contents or aggregate sources;
  • support specifications and acceptance testing for road construction projects.
• Particularly relevant to projects where timely compaction is critical for strength development and pavement performance.

Related standards

• prEN 13286-2: Proctor compaction (laboratory reference density and moisture content)
• prEN 13286-52: Making specimens by vibrocompression
• EN 13286 series (Parts 1–53) on unbound and hydraulically bound mixtures (road construction materials)

Keywords: EN 13286-45:2003, workability period, hydraulically bound mixtures, delayed compaction, sonic propagation, Proctor, vibrocompression, road construction materials, test method.