ESRM Validation Dataset: Serviceability Deflection Tests on 18 Slender RC Beams

This dataset contains the complete deflection calculation workbook for 18 simply-supported slender reinforced concrete (RC) beams tested under monotonic three-point bending at the Structural Engineering Laboratory, PAUSTI, Nairobi, Kenya. The dataset was produced to support independent validation of the Enhanced Stiffness Reduction Model (ESRM), a semi-empirical extension of the Branson (1963) effective moment of inertia formula. EXPERIMENTAL DESIGN 18 beams in a 3×3×2 full factorial design: three slenderness ratios (L/h = 18, 19, 20), three reinforcement levels (Low: ρ = 0.646%; Medium: ρ = 0.936%; High: ρ = 1.925%), and two concrete grades (M30: measured f'c = 31.2 MPa; M35: measured f'c = 36.1 MPa). Cross-section: b = 150 mm, h = 200 mm. Service deflection evaluated at 0.6Pmax (three-point loading, a/L = 0.5). One specimen per cell; no replication. INSTRUMENTATION LVDT (resolution 0.01 mm) at midspan soffit; FLAB-3-11-3LJC-F steel strain gauges at midspan; PL-60-11-3LJC-F concrete surface gauges at top and bottom fibres and web locations; computerised DAQ at 10 Hz. Loading frame: 25-ton rigid steel frame; 50-ton hydraulic jack; manual quasi-static load control. Support: pin-roller simply supported. WORKBOOK CONTENTS (5 sheets) 1. Cover: Workbook overview and colour-coding legend 2. Beam Properties: Section and material properties for all 18 beams 3. 18-Beam Calculations: Step-by-step Branson (ACI 318-19) and ESRM predictions for each beam, including all intermediate quantities (Mcr, Ma, Icr, Ie, κ-factors, δ) 4. Results Summary: Consolidated predicted vs. measured service deflection with error statistics (MAPE, mean bias, RMSE, coverage within ±10%) 5. Error Analysis: MAPE, mean bias, σ, and RMSE by subgroup (L/h, ρ, f'c) and globally KEY RESULTS Branson (ACI 318-19): MAPE = 24.48%, mean bias = +24.48% (entirely unconservative), RMSE = 3.82 mm, P(|ε|≤10%) = 11.1% ESRM (this study): MAPE = 4.86%, mean bias = +0.82% (near-zero), RMSE = 1.01 mm, P(|ε|≤10%) = 100% DATA QUALITY NOTE Two beams (B18-M-35 and B18-H-30) carry "Corrected δ_Meas assigned" flags in the Notes column reflecting corrections to the measured service deflection values from the initial data record. The Results Summary and Error Analysis sheets contain the authoritative values used in all published statistics. SOFTWARE Microsoft Excel (.xlsx). Compatible with LibreOffice Calc and Google Sheets. No macros.