Data underlying the publication: Creep in carbonatable binders: Investigating non-hydraulic lime mortars

CONTEXT:This dataset provides the experimentally measured total strain of air lime-containing mortars subjected to sustained compressive loading. The aim was to investigate long-term deformation behavior and support the development of reproducible testing protocols for non-hydraulic binders, such as air lime.
GROUPS & MATERIALS:Mortars were prepared with four binder compositions—C100L0, C50L50, C33L67, and C0L100—representing varying proportions of Portland cement (CEM II A/L 32.5R) and air lime (CL90-S). The number after 'C' represents the percentage of cement (compared to the total binder volume), while the number after 'L' represents the percentage of air lime (over the total binder volume). Thus, C33L67 means that 33% of the binder composition is Portland cement and 67% of the binder composition is air lime. Standard siliceous sand (0-2 mm, EN 196-1:2016) and tap water were used. The specimens were exposed to different curing environments (Curing regimes A, B, and C) and monitored under load for periods up to 240 days.
PRODUCTION OF SPECIMENS:To ensure that all mixtures were suitable for the same intended application, the flow diameter was fixed at (164 ± 7) mm, in line with the procedure recommended by EN 459-2:2021. Regarding specimen production, the same mixing procedure was adopted for all four mortar groups. Mixing lasted four minutes, followed by casting in two layers. Each layer was compacted using mechanical vibration for 30 seconds, in line with the instructions provided in EN 459-2:2021 and EN 196-1:2016.
CURING CONDITIONS:After initial curing for 7 days in a humid chamber at (95 ± 5) % RH and (21 ± 2) °C (EN 1015-11:2019), specimens were subjected to three curing regimes:Curing regime A: at natural atmospheric conditions (~0.04 % CO₂), until reaching 28 days.Curing regime B: at natural atmospheric conditions (~0.04 % CO₂), until reaching 91 days.Curing regime C: in an accelerated carbonation chamber (1 % CO₂), until reaching 28 days.Throughout curing and testing, all groups were maintained at (21 ± 2) °C and (55 ± 5) %. Except for C100L0 (Curing regime A), which was kept at (95 ± 5) % RH, (21 ± 2) °C, and (~0.04 % CO₂) until reaching 28 days, in accordance with EN 1015-11:2019.
TESTING PROTOCOL:The acquisition of strain data was conducted in accordance with EN 12390-17:2019. Each binder composition under each curing regime was loaded to 30% of its compressive strength, determined at 28 days (Curing regimes A and C) or 91 days (Curing regime B).Curing regime A specimens were monitored for up to 56 days.Curing regimes B and C were monitored for 240 days.Two prisms per mixture (10 × 10 × 40 cm) were tested, yielding four measurement points per condition. Total displacement was measured continuously with automated LPDTs (±0.0001 mm), recorded every 30 seconds during the first week and every 30 minutes thereafter. Strain was calculated using a 20 cm gauge length.
VALUE OF THE DATA:This dataset provides long-term total strain records (up to 240 days) for air lime-containing mortars subjected to standardized loading conditions (30 % of each group’s reference strength) under well-defined curing regimes (0.04 % and 1 % CO₂). It includes four binder compositions ranging from pure cement to pure air lime (binder-volume percentages defined in the CxLy codes). These data allow researchers to assess how binder composition and curing regime influence long-term deformation and volume stability, and to evaluate the applicability and limitations of EN 12390-17 when extended to non-hydraulic binders.