Recently, the 41st Xiamen Geotechnical Engineering Academic Symposium (Academic Salon) was successfully held at the Xiamen Peony International Hotel. The salon was hosted by the Xiamen Society of Civil Engineering and Architecture, and co-organized by the Society's Geotechnical Engineering Professional Committee and the Xiamen Branch of China Jingye Engineering Technology Co., Ltd. The meeting was chaired by He Qingfeng, Executive Vice Chairman and Secretary-General of the Society. Lin Zhende, Deputy General Manager of China Jingye Xiamen Company, delivered a pre-meeting speech entitled "The tide is flat, the two banks are broad; the wind is right, a sail hangs high" and a factual account of the 40th anniversary of the MCC Construction Research Institute's participation in the construction of the Xiamen Special Economic Zone.

      The symposium focused on topics such as "Design Selection and Case Analysis of Super-Large Foundation Pit Support", "Discussion on Several Applications of Geophysical Prospecting Technology in Geotechnical Engineering Investigation", "Discussion on the Influence of Water on Slope Treatment Design", and "Application and Discussion of Dynamic Compaction Technology in Foundation Treatment". More than 70 technical experts and guests from over 40 survey and design institutes, construction drawing review agencies, and universities participated in the academic discussion.

      Professor-level Senior Engineer Yang Zhiyin, an expert enjoying special government allowances from the State Council and a Guangdong Provincial Engineering Survey and Design Master, elaborated on the characteristics of super-large foundation pits around the design selection and examples of super-large foundation pit support, proposed some problems faced in the design of super-large foundation pits, and introduced the selection of several commonly used support methods for super-large foundation pit support design. Through the analysis of super-large foundation pit support design examples, he summarized the problems that should be noted in the design process of super-large foundation pit support, solutions, and countermeasures, providing reference experience for similar projects.

      Dr. Chang Fangqiang, Associate Professor at Huaqiao University, introduced several practical techniques in seismic exploration and electrical exploration, and discussed their applications in bedrock depth determination, boulder detection, groundwater detection, reservoir dam leakage detection, and engineering geological surveys.

     Senior Engineer Huang Qingxiang, Deputy Chief Engineer of Jingye Xiamen Branch, based on the design and construction process of a mine slope geological disaster treatment and a building slope treatment project, introduced the impact of rainfall, surface water, and groundwater on reducing slope stability through data collection and analysis. Through case summaries, it was concluded that geotechnical engineering design is often affected by comprehensive factors such as economic considerations and incomplete investigations, which affect slope safety; emphasis should be placed on the principles of dynamic design and information-based construction for slope engineering, especially for slopes sensitive to groundwater.

     Lin Zhimin, Manager of the Technical Quality Department of Jingye Xiamen Branch, titled "Application and Discussion of Dynamic Compaction Technology in Foundation Treatment", summarized experiences from several dynamic compaction cases, analyzed the applicability of dynamic compaction in special strata, the selection of key parameters, and issues to note in the treatment of deep fill soft foundations, providing references for how to adapt dynamic compaction technology to local conditions and effectively solve foundation treatment problems.

     During the discussion and exchange session, participants spoke actively and had in-depth discussions on the four topics and shared their insights; they discussed issues related to water-stop of secant piles in super-large foundation pit support design cases, the stiffness and calculation methods of three-level stepped support design, deformation control of foundation pits adjacent to subways, the combination of geophysical prospecting and in-situ testing with urban renewal and AI artificial intelligence, and the important factor of water in slope disasters and treatment, emphasizing the principles of dynamic design and information-based construction in geotechnical engineering, the applicability of dynamic compaction in fill layers, and the calculation methods for post-construction settlement. They proposed a new research direction of combining AI artificial intelligence technology with empirical disciplines.

     Lin Longhui, Chairman of the Geotechnical Engineering Professional Committee of the Xiamen Society of Civil Engineering and Architecture, made a concluding speech. First, Master Yang Zhiyin provided many classic cases in the selection of super-large foundation pit support, especially in areas where the use of pile anchors is restricted, and proposed valuable experiences of different support design ideas such as inclined piles + anchor cables and compartment method. Second, in the field of engineering investigation, geophysical prospecting has unique advantages in detecting boulders, caves, groundwater, and bedrock. If AI artificial intelligence is deeply integrated with geophysical prospecting technology, self-learning and continuous adjustment of detection process data will greatly improve the accuracy of geophysical prospecting. Third, slope problems are generally caused by water, such as long-term rainfall and blockage of groundwater channels during construction, which can lead to rising groundwater levels, increased slope weight, reduced soil strength, and slope collapse. Therefore, designers should pay attention to the principles of dynamic design and information-based construction in geotechnical engineering. Fourth, dynamic compaction is a mature technology with low cost and relatively simple construction. Its applicability should be noted in the foundation treatment of fill layers, especially in the presence of deep soft soil layers, and should be used with caution.

Source: Xiamen Society of Civil Engineering and Architecture