In this study, centrifuge model tests were used to examine the lateral behavior of amonopile embedded in dry sand through cyclic lateral loading tests. The soil specimens used in thetests were dry Jumunjin sand with a relative density of 80% and a friction angle of 38°. A staticloading test was performed once, and cyclic loading tests were performed four times using fourmagnitudes of cyclic load (30%, 50%, 80%, and 120% of static lateral capacity). The experimentalcyclic p‐y curve was obtained through the tests, and the maximum soil resistance points that werefound for each load were used to find the cyclic p‐y backbone curve for each depth. The twovariables which are needed to define the cyclic p‐y backbone curve, i.e., the initial modulus ofsubgrade reaction (kini) and ultimate soil resistance (pu), were suggested as functions of the soil’sphysical properties and the pile. The cyclic p‐y curve of the first cycle and the 100th cycle wereformulated to present the upper limit and lower limit. The suggested cyclic p‐y curve had anoverestimated soil resistance compared with the existing API (1987) method, but the initial modulusof subgrade reaction was underestimated.

The objective of this study is the investigation of the influence of carbonation on the penetration of chloride ions in reinforced concrete sections for different mix proportions and environmental conditions. A comprehensive numerical model based on the change of the pore structure and the chemical equilibrium was used for this combined action of carbonation and chloride ingress. The empirical formulae of some parameters in this model are estimated according to numerous experimental data. And, a set of data analysis is carried out to simplify the estimation of model variables to reduce the computational cost. A coupled simulation of the transports of carbon dioxide, chloride ions, heat and moisture is carried out. Then, the parametric analysis is given and the numerical results show that the effect of carbonation of the free chloride ingress is significant and depends on the binder types and concrete mix proportion.

In this study, the cyclic lateral behaviors of an offshore monopile in saturated dense sand under cyclic loading was investigated using centrifuge model tests. The soil used for testing was Jumunjin sand, which was deposited with a relative density of 80 %. A static loading test was carried out to obtain the static lateral capacity of the monopile, from which the magnitudes of cyclic load were determined at 30 %, 50 %, 80 %, and 120 % of the lateral capacity. A hundred cycles were applied to the pile head with the frequency of 0.125 Hz. Experimental cyclic p-y curves were obtained at 2, 5, and 7-m depths, from which equations for cyclic p-y curves for saturated dense sand were proposed. The proposed p-y curve was compared with the conventional p-y curves; it was found that the proposed equations overestimate the ultimate soil resistance compared with the conventional ones, whereas the initial modulus of subgrade reaction was only 35 % the conventional ones.

This paper investigated the similitude law for strip footing resting on cohesionless soils. 2D finite element analyses were employed to estimate the ultimate unit bearing pressure of strip footing in three different conditions: laboratory model test under 1-g, centrifuge test under n-g, and full scale test under 1-g. The Hardening Soil model was used for cohesionless soil to account for the increase in shear strength and stiffness with depth. Based on the numerical results, the axial unit bearing pressure-settlement curves were collected. The ultimate unit bearing pressures and settlements for three simulations were compared, and stress scale ratio and geometric scale ratio were drawn such that ultimate unit bearing pressure in full scale test could be estimated from laboratory test results.

The influence of skirt to the seismic behavior of the bucket foundation supporting offshore wind turbine was analyzed by performing dynamic centrifuge tests. Three types of bucket foundation with aspect ratios (length of the skirt/diameter of the foundation) of 0.50, 0.75 and 1.00 were tested. Kobe and El Centro earthquakes were used as excitation patterns. Clean sand was used to simulate the soil deposit. Peak acceleration, settlement and tilting of foundations on drained sand condition were analyzed and compared. The bucket foundation with the longest skirt accelerated the most at the platform level and experienced the least degree of tilting and normalized settlement. Obtained results were expected to contribute for a better understanding on the performance of bucket foundation during an earthquake.