SETTLE Settlement Effects, Trough Topology and Local Evolution Assessment

Abstract

This paper presents SETTLE — Settlement Effects, Trough Topology and Local Evolution Assessment, the current terrain-side assessment module of the integrated IAS-DX framework for deep excavations. SETTLE represents the current and canonical methodological development of the earlier WNO/STII/SII settlement-trough assessment line. It consolidates the technical content developed in the preceding WNO/STII versions and reorganises it under the final English naming standard adopted for IAS-DX. The earlier WNO, STII and SII terms are retained as methodological sources and historical equivalents of the settlement-trough irregularity core now incorporated into SETTLE. SETTLE is responsible for the interpretation of excavation-induced settlement effects, settlement-trough morphology, terrain deformation, irregularity, local anomalies, dynamic influences and geometry-based evidence obtained from scanning or three-dimensional measurements. Within IAS-DX, it receives structured input data from DOCC, provides the terrain-side demand for OSCAR and transfers dominant terrain-response mechanisms to MATCH for technical-control selection. The framework extends the earlier morphology-oriented WNO/STII concept into a broader terrain-side assessment system. It evaluates settlement intensity, deformation intensity, settlement-trough morphology, asymmetry, local anomalies, object-trough intersection, dynamic influence, scan-based geometry evidence and reliability. The morphology component preserves the original WNO/STII logic based on deviation from a reference profile, curvature, settlement-area asymmetry, local anomaly and displacement of the maximum settlement point. These descriptors are no longer treated as an isolated irregularity indicator but as part of the wider SETTLE terrain-response architecture. SETTLE retains the Reference Profile Selection and Verification Module introduced in WNO/STII 3.0. The reference profile is treated as a documented analytical baseline rather than an arbitrary background curve. Its selection should therefore reflect the available data, excavation mechanism, monitoring stage, numerical or analytical assumptions and intended interpretation. The framework also retains the reference-width sensitivity, settlement-concentration, centroid and time-variability descriptors introduced in WNO/STII 3.1. These components allow the analyst to assess whether the morphology result is sensitive to the adopted trough width, whether settlement effects are locally concentrated or broadly distributed, where the centroid of the settlement field is located and whether the trough is stabilising, developing or becoming more irregular between monitoring stages. SETTLE incorporates two additional cross-cutting diagnostic components. IDYN represents dynamic influences, including vibration-related effects relevant to terrain response. ISCAN represents geometry-based evidence obtained from terrestrial scanning, point clouds, photogrammetry, three-dimensional displacement measurements, surface geometry or other spatial observations. The reliability component records the strength of the available evidence. SETTLE results are therefore reported together with a reliability level rather than interpreted solely from a numerical score. High, medium and low reliability classes distinguish between well-documented, partially confirmed and sparse or weakly documented input data. Where a single integrated terrain-side result is required, the individual SETTLE components may be normalised and combined into the integrated ISETTLE index. The final result is expressed through a SETTLE class together with the dominant terrain-side mechanisms and reliability level. The purpose is not to reduce terrain behaviour to a single number, but to provide a structured and auditable representation of the mechanisms controlling the assessment. SETTLE may be applied to monitoring profiles, analytical or empirical settlement distributions, numerical-model results and appropriately documented scanning or three-dimensional datasets. The source, density, reliability and spatial representativeness of the input data should always be stated. The framework is conceptual and methodological. It does not replace geotechnical design, numerical modelling, field monitoring, structural assessment, project-specific verification or expert engineering judgement. The proposed component weights, interpretation thresholds and integrated classification should be calibrated and validated using measured settlement data, documented field observations and deep-excavation case studies. Within the IAS-DX architecture, SETTLE operates in the following sequence: DOCC → SETTLE → OSCAR → MATCH → IAS-DX DOCC provides the structured documentation and input-data basis. SETTLE evaluates the terrain-side demand. OSCAR evaluates the susceptibility, coupling and response of the adjacent object. MATCH then selects the mechanism-matched technical control mode. SETTLE transfers to OSCAR the terrain-side class, integrated index, morphology result, settlement and deformation indicators, asymmetry, local anomalies, object-trough intersection, IDYN and ISCAN descriptors and reliability level. It also provides MATCH with the dominant mechanism required for selecting an appropriate technical-control state. The original contribution of SETTLE lies in the systematic integration of settlement intensity, deformation intensity, settlement-trough topology, morphology irregularity, local evolution, reference-profile reliability, dynamic influences and spatial geometry evidence into a single terrain-side assessment module capable of communicating directly with the remaining IAS-DX components. SETTLE — Literature and Methodological Context SETTLE is positioned within established engineering knowledge concerning deep excavations, excavation-induced ground movements, settlement troughs, differential settlement, angular distortion, curvature, geotechnical monitoring, tunnelling-related settlement profiles, soil–structure interaction, dynamic effects and spatial deformation measurement. The current SETTLE framework was developed through a sequence of earlier authorial methodological stages. Immediately preceding SETTLE, WNO/STII 3.1 extended the morphology framework with reference-width sensitivity, concentration and centroid descriptors and time-variability assessment. Before this, WNO/STII 3.0 formalised the Reference Profile Selection and Verification Module, data-quality classes, uncertainty interpretation, sensitivity review and synthetic benchmark profiles. The preceding WNO/STII 2.0 retained the original five-component morphology structure while introducing an operational interpretation layer linking dominant morphology components, data confidence and monitoring response. The methodological line originates from WNO/STII — Settlement Trough Irregularity Indicator, the original morphology-oriented framework developed to describe deviation from a reference settlement profile, curvature, settlement asymmetry, local anomalies and displacement of the maximum settlement point in settlement troughs generated near deep excavations. Methodological development line: SETTLE → WNO/STII 3.1 → WNO/STII 3.0 → WNO/STII 2.0 → WNO/STII References and Methodological Background Authorial methodological lineage [1] Florczak, M. (2026). WNO/STII 3.1: Extended Methodological Framework for Settlement Trough Morphology, Reference-Width Sensitivity and Time-Variability Assessment. Conceptual methodological preprint. [2] Florczak, M. (2026). WNO/STII 3.0: Scientifically Refined Methodological Framework for Settlement Trough Irregularity Assessment. Conceptual methodological preprint. [3] Florczak, M. (2026). WNO/STII 2.0: Settlement Trough Irregularity Indicator — Operational Interpretation Framework for Deep-Excavation Settlement Profiles. Conceptual methodological preprint / revised operational version. [4] Florczak, M. (2026). WNO/STII — Settlement Trough Irregularity Indicator: A Supporting Tool for the Assessment of Deep Excavation Impact. Conceptual methodological preprint. To dokładnie odpowiada rozwojowi, który SETTLE sam deklaruje: 2.0 wnosi operational interpretation, 3.0 reference-profile verification, 3.1 width sensitivity/concentration/centroid/time variability, a wszystkie te elementy są następnie skonsolidowane w SETTLE. Engineering and scientific background [5] Peck, R. B. (1969). Deep excavations and tunneling in soft ground. 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