# Excavation and Construction Technology of Diversion Tunnel under Complex Geological Conditions
## 1 Introduction  
With the rapid development of China's economy and the acceleration of urbanization, water conservation and hydropower engineering construction have become important means to promote economic development, improve people's livelihoods, and ensure energy security [1]. As an important component of hydropower engineering construction, the excavation and construction technology of diversion tunnels has also received widespread attention and research. The progressiveness and practicability of the diversion tunnel excavation construction technology directly affect the efficiency and safety of the project construction, which is of great significance [2].  
The construction technology of diversion tunnel excavation is a complex engineering system that requires the comprehensive application of multidisciplinary knowledge such as geology, mechanics, hydrology, etc. Reasonable construction plans and technical routes for different geological conditions and engineering requirements need to be developed, with the aim of improving the quality of engineering construction [3, 4].  
[PERSON] et al. [5] comprehensively consider the impact of random changes in construction activity time, construction machinery failures, and risks such as landslides and water inrush on the construction of diversion tunnels and propose a method for selecting construction plans for diversion tunnels that considers the impact of risk factors. This method first establishes an optimization model for tunnel construction plans that considers the impact of risk factors, and then uses the Levy Flight Adaptive Chaos Particle Swarm Optimization (LFACPSO) algorithm to solve the model to obtain a set of construction plans. The LFACPSO algorithm introduces Levy flight to improve the ability of particles to jump out of local optima, while using a chaos algorithm to initialize particles and adaptively adjust particle inertia weight coefficients. Finally, the Intuitive Fuzzy Entropy Weighted Power Average (IFEWPA) method is used to select the final excavation construction plan from the set of options, taking into account expert evaluation hesitation. [PERSON] et al. [6] elaborated on key technologies such as precise blasting vibration control, treatment measures for special geological conditions of tunnel sections, rapid lining of needle beam trolleys, and information construction for personnel tracking and positioning for the diversion tunnel at the head of the North South Main Canal of the Xiangjiaba Irrigation Area Project, which stabilized the deformation of the surrounding rock after excavation and ensured the safety of the lining structure.  
Due to different geological conditions, there are many difficulties and challenges in the actual excavation construction process [7]. For example, complex tectonics, uneven geological body properties, and poor hydrogeological conditions have brought great risks and challenges to the excavation and construction of diversion tunnels.  
In order to overcome these difficulties and challenges and improve the efficiency and safety of diversion tunnel excavation construction, this study designs new construction techniques for diversion tunnel excavation construction projects under complex geological conditions. This technology innovatively combines TSP technology for advanced geological prediction, uses detection technology to calculate the spatial orientation and length of the main tunnel, and designs multiple excavation construction techniques and quality control systems, improving the efficiency and safety of excavation of the diversion tunnel under complex geological conditions.