Cycle-resolved friction evolution and apparent endpoint energy-to-wear ratios for cementitious-material–rock contacts under debris-flow-like reciprocating sliding

This dataset supports the manuscript entitled “Abrasion resistance of cementitious materials under debris-flow-like sliding: Three-stage friction modelling and apparent endpoint energy-to-wear ratios”. The dataset contains cycle-resolved processed friction coefficients; representative force–displacement loops; endpoint cumulative dissipated energy and wear volume; derived apparent endpoint ratios linking wear volume to cumulative dissipated energy; raw profilometer exports and their file mapping; archived nanoindentation records; logarithmic fitting bins; fitted parameters; alternative-model comparisons; binning and edge-sensitivity analyses; temporal-holdout results; and Python code for reproducing the segmented friction-model fits. The experimental matrix comprises three cementitious materials (C1 and C3 standard-sand mortars and C2 hardened cement paste) paired with three rock counterparts (D, a rock collected from a debris-flow channel; S1, shale; and S2, sandstone). The contact pairs were tested under Water, kaolin-containing Debris-slurry and selected Dry conditions. The reciprocating abrasion tests were conducted under a normal load of 50 N, a cyclic tangential displacement of ±5000 µm, a loading frequency of 1 Hz and a duration of 3000 cycles. Nineteen primary friction histories are used for model fitting. One independent C3–D–Water repeat is included only for a descriptive assessment of the repeatability of the friction history and cumulative dissipated energy; no independent replicate wear volume is available for this condition. The reported endpoint ratios are therefore contact- and condition-specific descriptors. They should not be interpreted as universal material constants, evidence of process-wide linear energy–wear behaviour or independently validated constitutive parameters. The complete unmodified high-frequency force–displacement archive, approximately 30 GB in size, is not included because each condition file exceeds 1 GB. It is available from the corresponding author on reasonable request. Cycles within one test, indentation positions within one specimen and transverse profiles across one wear scar are not independent abrasion-test replicates.