Settlement Relevant Load Combination Regarding Structural Design

Settlement-relevant load combinations play a critical role in the serviceability design of buildings, particularly for structures on soils with time-dependent deformation behavior. While permanent loads must be fully considered, the contribution of variable actions de-pends on their duration relative to soil response. This study investigates appropriate set-tlement-relevant load combinations for structural design by combining literature data, numerical analysis, and parametric simulations of two structural systems (wall-type and frame-type) on different soil types. Numerical analyses in PLAXIS 3D evaluate the influ-ence of different load combinations and soil permeability on settlement distribution and load redistribution. Results show that for coarse-grained soils under drained conditions, the reduced characteristic load combination (including αn) offers a balanced, realistic, and safe choice regarding the force redistribution within the building, while for fine-grained soils the quasi-permanent combination is recommended. National Annexes from the UK and France allow further reduction through lower αn values, potentially improving design efficiency without compromising safety. Sequenced loading concepts after long-term con-solidation are negligible for settlement-relevant design but may be considered in stratified soils.