Analytical solutions for surface deformation induced by jacking large-section pipe curtain box culvert

It is of great significance to study the influences of the whole jacking process of a curtain box culvert on soil deformation and surrounding environment in advance to predict the deformation and control the influences of construction disturbance. A method for calculating the surface deformation under the combined action of front propulsion, friction and soil loss is obtained based on the classical theoretical solutions such as the Mindlin solution and revised Sagaseta formula. The mechanical model for soils under the jacking process of the curtain box culvert is established, and the formula for the soil deformation caused by the front propulsion force and friction force is given based on the Mindlin solution. The formula for the lateral surface settlement caused by the soil loss is proposed based on the principle of the equivalent layer method. According to the relative independence of each influencing factor, the deformation caused by each factor is superimposed to obtain a theoretical solution formula suitable for jacking of the large-section pipe curtain box culvert, which can comprehensively consider a variety of construction factors and three-dimensional deformation of soils. The rationality of the formula is verified through engineering examples, and the research results can provide references for the deformation prediction of actual construction.