Xuanming Ding

Bio: Xuanming Ding is an academic researcher from Chongqing University. The author has contributed to research in topics: Pile & Geotechnical engineering. The author has an hindex of 19, co-authored 104 publications receiving 1075 citations. Previous affiliations of Xuanming Ding include Hohai University.

Application of deep learning algorithms in geotechnical engineering: a short critical review

Abstract: With the advent of big data era, deep learning (DL) has become an essential research subject in the field of artificial intelligence (AI). DL algorithms are characterized with powerful feature learning and expression capabilities compared with the traditional machine learning (ML) methods, which attracts worldwide researchers from different fields to its increasingly wide applications. Furthermore, in the field of geochnical engineering, DL has been widely adopted in various research topics, a comprehensive review summarizing its application is desirable. Consequently, this study presented the state of practice of DL in geotechnical engineering, and depicted the statistical trend of the published papers. Four major algorithms, including feedforward neural (FNN), recurrent neural network (RNN), convolutional neural network (CNN) and generative adversarial network (GAN) along with their geotechnical applications were elaborated. In addition, a thorough summary containing pubilished literatures, the corresponding reference cases, the adopted DL algorithms as well as the related geotechnical topics was compiled. Furthermore, the challenges and perspectives of future development of DL in geotechnical engineering were presented and discussed.

Influence of Particle Breakage on Critical State Line of Rockfill Material

Abstract: The influences of particle breakage on the position of the critical state line (CSL) were systematically investigated in this paper through a series of large-scale triaxial compression tests on Tacheng rockfill material (TRM). It was found that the critical-state stress ratio of TRM (i.e., the gradient of the CSL in the p−q space) was approximately regarded as a constant. In the e−logp space, the CSL of TRM descended with a decrease in the initial void ratio, whereas the gradient of the CSL was constant. A procedure was established for evaluating the critical state point at a same particle breakage, which comprised the breakage critical state line (BCSL). An increase of the particle breakage led to not only a vertical translation but also a rotation on the BCSL of TRM in the e−logp space, which was similar to the observation of Dog’s Bay sand. Consequently, the initial gradation (or the corresponding initial void ratio) was the dominant factor that affected the position of the CSL of TRM in the e−...

The detailed particle breakage around the pile in coral sand

Abstract: Detailed particle breakage adjacent to a pile has great influence on the settlement and bearing capacity of a pile foundation. Before the pile test, coral sand was divided into different grain-size groups and dyed in different colors, then mixed as the ground soil. After pile penetration, the sand around the pile was divided into many zones and sampled. Grains in different colors in each size range of each sample were discerned quantitatively. Results show that the settlement curve dropped fast and the skin friction of pile was small due to the obvious particle breakage. In each zone, the actual particle breakage in each size range was different from the change in relative mass percentage, and the lost of angular edges is the dominant type of particle breakage under the bottom pressure of pile. The index Bag, excluding the interference effect of size overlap between fragments and unbroken grains in each size range, was slightly larger than Bg for most zones around the pile. The breakage-zone was limited to 1.5 times of the pile diameter at the radial direction and 2.5 times at the depth direction, which is much deeper than that in silica sand. Particle breakage at some distance from pile bottom is larger than that at the very bottom of the pile due to the shearing effect in the sand. Detailed particle breakage around the pile is useful in studying the interaction between the pile and crushable granular soil.

Wave Propagation in a Pipe Pile for Low-Strain Integrity Testing

Abstract: This paper presents an analytical solution methodology for a tubular structure subjected to a transient point loading in low-strain integrity testing. The three-dimensional effects on the pile head and the applicability of plane-section assumption are the main problems in low-strain integrity testing on a large-diameter tubular structure, such as a pipe pile. The propagation of stress waves in a tubular structure cannot be expressed by one-dimensional wave theory on the basis of plane-section assumption. This paper establishes the computational model of a large-diameter tubular structure with a variable wave impedance section, where the soil resistance is simulated by the Winkler model, and the exciting force is simulated with semisinusoidal impulse. The defects are classified into the change in the wall thickness and Young’s modulus. Combining the boundary and initial conditions, a frequency-domain analytical solution of a three-dimensional wave equation is deduced from the Fourier transform method and the separation of variables methods. On the basis of the frequency-domain analytic solution, the time-domain response is obtained from the inverse Fourier transform method. The three-dimensional finite-element models are used to verify the validity of analytical solutions for both an intact and a defective pipe pile. The analytical solutions obtained from frequency domain are compared with the finite-element method (FEM) results on both pipe piles in this paper, including the velocity time history, peak value, incident time arrival, and reflected wave crests. A case study is shown and the characteristics of velocity response time history on the top of an intact and a defective pile are investigated. The comparisons show that the analytical solution derived in this paper is reliable for application in the integrity testing on a tubular structure.

Dynamic response of pile groups subjected to horizontal loads

Abstract: This paper presents an analytical method for calculating the dynamic impedance of pile groups comprising an arbitrary number of cylindrical piles connected with a rigid cap. The solution allows con...

Neocognitron--A New Algorithm for Pattern Recognition Tolerant of Deformations and Shifts in Position

Abstract: Suggested by the structure of the visual nervous system, a new algorithm is proposed for pattern recognition. This algorithm can be realized with a multilayered network consisting of neuron-like cells. The network, “neocognitron”, is self-organized by unsupervised learning, and acquires the ability to recognize stimulus patterns according to the differences in their shapes: Any patterns which we human beings judge to be alike are also judged to be of the same category by the neocognitron. The neocognitron recognizes stimulus patterns correctly without being affected by shifts in position or even by considerable distortions in shape of the stimulus patterns.

Closure to “Load Transfer for Axially Loaded Piles in Clay”

Abstract: An analytical method for developing a theoretical load-settlement curve for axially loaded piles in clay is presented. The method is based on the correlation of the ratio of load transfer to soil shear strength as a function of pile movement. The results of studies of field tests of instrumented piles and laboratory tests of small piles in clay are used to obtain the desired correlation. The correlation is presented in the form of a family of curves that are obtained when the ratios of load transfer to soil shear strength versus pile movement are plotted as a function of depth. The validity of the family of correlation curves is checked by comparing computed and actual load-settlement curves for some typical field tests. Results obtained by this method indicate that the method may be used effectively to determine load-carrying capacity for axially loaded piles in clay.

P-ultimate for undrained analysis of laterally loaded piles. discussion and closure

Abstract: A discussion of a paper with the aforementioned title by Murff and Hamilton, published in this journal (Volume 119, Number 1, January 1993), is presented The discussion focuses on laterally loaded piles in layered soils Maugeri, Castelli, and Motta assert that the authors' method overpredicts the ultimate lateral resistance on the pile Discussion is followed by closure from the authors

Three-dimensional finite element modelling of a full-scale geosynthetic-reinforced, pile-supported embankment

Abstract: The performance of four sections of a full-scale embankment constructed on soft soil is examined using a fully coupled and fully three-dimensional finite element analysis. The four sections had sim...

Particle breakage and deformation of carbonate sands with wide range of densities during compression loading process

Abstract: In this technical note, evolutions of the particle size distribution, particle breakage, volume deformation and input work of carbonate sands with varying relative densities were investigated through performing a series of one-dimensional compression tests. Loading stress levels ranged from 0.1 to 3.2 MPa. It was found that the initial relative density could greatly affect the magnitude of particle size distribution, particle breakage, volume deformation and input work. Particularly, it was observed that the specimen at a lower relative density underwent much more particle breakage than that at a higher relative density. This could be attributed to the change of the coordination number with the initial density. However, a unique linear relationship between the particle breakage and input work per volume could be obtained, which is independent of the initial relative density.