Anthropogenic factors as determinants of deformation and damage of a bridge structure founded on clayed ground – a case study

Bridges are often built in complex geological-engineering conditions, on difficult soils, landslide areas or within the range of negative mining influences. These objects are classified as geotechnical category II or III and a ground investigation documentation or geotechnical design should be carried out for them. The correct investigation of the soil, design, and execution in accordance with technical knowledge, the art of construction and the Building Code are a guarantee of the safety of the facility. However, very often it is the complexity of the geological structure, concentrated vertical and horizontal loads transferred by the supports to the soil that make it necessary to use deep foundations, special methods of soil reinforcement and imposing a special technological regime during the execution of construction works. The paper pays attention to anthropogenic and natural factors, as well as those that are the consequence of inappropriate human actions at the design or execution stage. Particular attention is paid to errors in the soil analysis and execution of construction works. An example of such errors analysis is presented in relation to the implementation of a bridge structure.