Axisymmetric Arc Sliding Method of Basal Heave Stability Analysis for Braced Circular Excavations

Abstract

On the basis of the circular arc sliding model of the limit equilibrium method, an axisymmetric arc sliding method (AASM) is proposed to analyze the basal heave stability of braced circular excavations. The proposed method considers the stiffness of the enclosure structure and spatial effects. The AASM was applied to check basal heave stability in a design example and provided results that were more reasonable than those obtained using other methods. The radii effects in theory and numerical simulation, and the enclosure structure stiffness effects on the basal heave stability safety factor were discussed. Additionally, the effects of the embedded depth on the basal heave stability of a braced circular excavation were analyzed. The safety factor of basal heave stability for a braced circular excavation will be larger when calculated with the AASM than when calculated with the circular arc sliding method, and the optimized embedded depth of the enclosure structure may therefore be reduced by 4∼5 m to lower the cost of the enclosure structure.

Low Carbon Optimization of Deep Foundation Pit Support in Undulating Strata

“…Zheng Gang et al [1] used the limit balance method to analyze the failure mode of the single-row supported foundation pit and the influence of engineering piles in the pit on the stability of the foundation pit. Zhang Fei et al [2] used the limit analysis method to study the stability of the foundation pit. Lv N [3] analyzed the design with the equivalent beam method of single fulcrum row piles in a deep foundation pit retaining structure.…”

Estimating the Basal Heave Stability of Narrow Braced Excavations

“…Estimating the basal heave stability of braced excavation is quite significant for design. Up to the present, it can be performed by using the limit equilibrium method (LEM) [2,[8][9][10][11][12][13][14][15][16][17][18][19], limit analysis method [9,[20][21][22][23][24], probabilistic method [2,10,[25][26][27][28][29][30][31][32], and finite element method (FEM) with shear strength reduction technique (SSRT) [2,10,15,20,[33][34][35][36][37][38][39][40].…”

“…e limit equilibrium method can be divided into two categories [15,19,21,24]: the bearing capacity method [8,9,13,16,17] and the slip circle method (SCM) [11,16,18,19]. e stability models proposed by Terzaghi [17] and Bjerrum and Eide [8] are based on bearing capacity theory [2,15,19,32,40]. For these two types of methods, factors of safety (F s ) are both defined as the ratio of the resistance over the load [15,34].…”

“…Reliability theory logically considers the uncertainty in the soil parameters [15], where the design variables are considered random in nature [25]. Many studies on reliability analysis [26,[28][29][30][31][32] have been carried out using the slip circle model [19] on account of its simplicity and suitability for modeling random fields [28]. Above all, it does not assume homogeneity [32].…”