To ensure the safety of project construction and reduce development costs, it is necessary to obtain a reasonable design before project initiation and to analyze and study geological information from multiple perspectives to achieve intuitive and effective project planning. Therefore, it is proposed to integrate above- and underground information to realize integrated spatial information expression. Generally, geological body model construction is based on drilling data, but most geological bodies are not simple layered structures, and complex geological phenomena usually occur, such as faults, lenses, and fissures. It is difficult to construct a high-quality geological body model with only limited drilling data. To fully consider existing geological information in complex geological areas with limited geological data information available, profile maps are considered in the modeling process. This article focuses on the geological model construction of a primary school in Shuicheng County, Guizhou Province, using the GoCAD platform. The Structure and Stratigraphy Workflow is applied in three-dimensional geological body structure model establishment, the stratum rock mass is outlined, and the complex geological structure (karst cave) is embedded into the geological surface. The model can be sliced at any angle to accomplish integrated spatial information expression of above- and underground building information combined with the same platform’s geological body to obtain engineering information and analyze future construction problems.

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Biocementation mainly relies on the formation of calcium carbonate to bind soil particles. This paper investigates the effectiveness of biocementation in terms of treatment methods. The previously established two-phase methods are compared with newly developed one-phase-low-pH methods on their mechanical behavior and microstructure. The one-phase-low-pH methods present a higher urease fixation rate than two-phase methods, highlighting the cost-effectiveness of this method. A modified one-phase-low-pH using CH3COOH is also compared with HCl-based one-phase-low-pH method. The results show that the morphology and size of precipitated crystals have a great influence on strength development. An optimized treatment method based on the one-phase-low-pH method is also established, which is accomplished via the injection of 5 U/ml of bacterial culture together with 2 M of cementation solution during each treatment. After four times of treatments, a total of 7% cumulative calcium carbonate content can be obtained with an unconfined compressive strength of 2.15 MPa.

The strength and deformation properties of maritime geotechnical structures made primarily of calcareous sand are critical for project safety. The geogrid reinforcement is developed as a promising approach to improve the mechanical properties of calcareous sand. This study investigates the mechanical property of biomodified geogrid via a microbially induced calcite precipitation (MICP) process to improve the effectiveness of geogrid for reinforcement of calcareous sand. A series of unconsolidated undrained triaxial experiments were conducted to evaluate the mechanical property and deformation behaviors of biomodified geogrid and reinforced calcareous sand (BGRCS), taking into consideration the impacts of the geogrid layer, times of biotreatment, and confining pressure. Compared to the untreated geogrid, the strength of the BGRCS is distinctly changed due to the increase roughness, and the deviatoric stress-strain curves are evidently hardening. Strength and pseudocohesive force can be further enhanced by raising the geogrid layer of the reinforced specimens, while internal friction angle also increases the amplitude of variation with the times of biotreatment. The geogrid, times of biotreatment, and confining pressure are all intimately related to the strength and the deformation of the reinforced specimens. The interactions of geogrid ribs and calcareous sand particles are analyzed and friction using scanning electron microscope tests that could provide a reference for revealing the mechanical mechanism of BGRCS.