A method for determining the uplift amount after the bottom pile foundation of the saline soil cutting foundation bed is strengthened

Abstract

The invention relates to a method for determining the uplift amount after the bottom pile foundation of the saline soil cutting foundation bed is strengthened, which can scientifically and reasonablydetermine the uplift amount of the bottom pile foundation of the saline soil cutting foundation bed after consolidation, and can meet the needs of practical engineering. The method comprises the following steps: determining the neutral point depth l0 of the pile foundation in the saline soil, the atmospheric cooling influence depth l below the top surface of the cutting foundation bed, and calculating and determining the calculated thickness h0 of the pile foundation uplift deformation at the bottom of the cutting foundation bed; determining the temperature Ti 1 and other parameters of the i-layer soil before cooling in winter; carrying out salt dilatancy test, compression test, water content test, soil particle specific gravity test and weight test on saline soil samples to determine thesalt dilatancy index Csi of the i-th layer soil; determining the uplift amount se after the bottom pile foundation of the saline soil cutting foundation bed is strengthened by the following formula (shown in the description).

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering, in particular to a method for determining the amount of uplift after reinforcement of pile foundations at the bottom of a saline soil road cutting foundation bed. technical background [0002] At present, the amount of salt expansion (i.e. the amount of uplift) of saline soil foundations is mostly determined by the "Building Code for Saline Soil Areas" (SY / T0317—2012), that is, the amount of salt expansion is determined according to the following formula: [0003] S η0 =η·H [0004] In the formula, S η0 is the total salt expansion of the saline soil foundation, in mm; η is the salt expansion coefficient; H is the thickness of the effective salt expansion area, in mm. [0005] The saline soil foundation will bulge and deform under the condition of winter cooling, which can easily lead to cracking of ballastless track slabs of high-speed railways, causing major ballastless track...

AI Technical Summary

Problems solved by technology

[0005] The saline soil foundation will bulge and deform under the condition of winter cooling, which will easily cause the ballastless track slab of high-speed railway to crack, cause major ballastless track diseases, and even endanger the driving safety of high-speed trains

Pile foundation reinforcement can effectively control the uplift deformation of saline soil foundation, but there is no feasible method to determine the amount of foundation uplift after pile foundation reinforcement. Pile foundation replacement, pile foundation anchorage, the influence of saline soil's own gravity, especially for the reinforcement of saline soil pile foundation at the bottom of the road cutting foundation bed, let alone the influence of cutting excavation unloading and foundation bed load

Images