Irregular columnar jointed structure is a primary irregular columnar morphological tensile fracture. In order to study the geometric features of irregular columnar joints and the new problems in geotechnical engineering, hydraulic and hydropower engineering caused by columnar jointed basaltic mass, Voronoi graph from geometry was introduced to simulate the irregular columnar jointed basaltic mass at Baihetan hydraulic station. Discrete element software UDEC was used to simulate the whole process of rigid bearing plate test. Anisotropic constitutive of columnar joints was adopted to analyze the stress diffusion of rock mass at dam base of Baihetan. The results show that, the compaction property and hysteresis effect are well simulated based on discrete element simulation of Voronoi joint structure by UDEC. Four stages of cyclic loading and unloading process are imaged clearly. The results from in situ rigid bearing plate tests are explicated and the stress diffusion rule of anisotropic body is affected by structure surface. The elements in the stress state of 4−5 MPa are the most, about more than 35% of the total. Appropriate constitutive must be proposed to columnar jointed rock mass with different styles. It has important significance to realize the nonlinear mechanical behavior of irregular columnar jointed basaltic mass.

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To verify the positioning performance and reliability of multi-system combination Precise Point Positioning in landslide monitoring, we carried out a multi-system combination Precise Point Positioning calculation experiment on the monitoring data of a single landslide disaster area in Fujian Province. The coordinates of the monitoring points obtained by a continuously operating reference station and the monitoring station for static relative positioning were used as reference values. The GPS system was used as the standard system and the combined PPP solution mode of G/R/C, G/R/E and G/R/E/C was used to obtain the surface displacement of the landslide area. The research showed that multi-system combination PPP converges to the centimeter level in about 30 min. The average value of internal accordant precision was more than 1 mm after convergence, and that of the external accordant precision was more than 5 cm, which meets the centimeter-level accuracy requirements in rapid landslide deformation monitoring.

The application of electrical platform for converter station in offshore wind farm is highly forward-looking and strategic. The offshore electrical platform is complicated in structure, bulky in volume, and expensive in cost. In addition, the built-in electrical equipment is very sensitive to the acceleration response. Therefore, it is very important to study the hydrodynamic response of the electrical platform exposed in the open sea. Based on the elastic similarity, Froude similarity, as well as the flexural-stiffness similarity of the cross-section, the hydroelastic similarity was derived to guide the model test of a 10,000-ton offshore electrical platform in wind, wave, and current. The hydrodynamic responses including strain and acceleration at key positions of the structure were obtained for different incident angles of external environmental loads. The experimental results showed the increase of water depth can cause more than 10 times increase of strain and acceleration response of the platform. The attack angle of external environmental loads had no definite relationship with strain response of the structure. Therefore, the most dangerous attack angle cannot be determined. The strain of the structure under the combined action of wind, wave, and flow was significantly larger than that under wave load only.