Abstract:

The construction of deep excavations inevitably disturbs surrounding strata, particularly causing excessive surface settlement which can significantly threaten nearby buildings. It is essential to study surface settlement in excavations. To enhance current research on characterizing functions and indicators for surface settlement, we employ the skewed distribution function to describe surface settlement, and propose a set of indicator system applicable to excavations by scrutinizing the characterizing indicators of the settlement curves. On this basis, we put forward a skewed distribution function for predicting surface settlement. The applicability and effectiveness of the skewed distribution function as well as the indicator system and the prediction function in describing excavation-induced surface settlement are validated through analyzing two practical engineering projects. Findings demonstrate the rationality of the skewed distribution function in describing excavation-induced surface settlement. The characterizing indicator system, with explicit and implicit indicators at its core, takes into consideration the settlement curve envelope area, the maximum surface settlement and its location. Regression and prediction using the skewed distribution function demonstrate a close alignment between predicted settlement curves and actual data, confirming the function's rationality and applicability for describing surface settlement in excavations.

Key words: excavation engineering, surface settlement, skewed distribution, characterization function, characterization indicator