In order to reveal the evolution of bonding performance of HIRA (High Intensity and Rapid Agent) anchor solids with maintenance time, the evolution characteristics of bond strength and stress distribution at the interface between HIRA-based anchor solids and a geotechnical body under different maintenance times and the fine damage pattern of anchor solids were studied by an indoor pull-out test of anchor solids. The comparative analysis was performed with 42.5 grade ordinary Portland cement (hereinafter referred to as P.O 42.5). The results show that the early strength and rapid setting characteristics of HIRA type material are obvious, and the difference between its average peak bond strength and that of cement is 10.45 times. The shear stress distribution has obvious stress concentration characteristics, and the peak value will appear and shift with the increase in load, and the peak shift of the HIRA anchor solid occurs earlier than that of cement. Due to different stress levels, the damage of the HIRA anchor solid after being pulled out increases with the increase in maintenance time, while that of cement gradually becomes more severe. The overall damage of the HIRA material is generally lower than that of cement in the same period.

A new type of composite cement-based cementing material—high-strength fast cementing material (HSFCM)—will be widely used in marine engineering projects such as submarine tunnels. However, the influence of fire and other high temperature conditions on its material properties have not been explored in previous studies. Mechanical tests and microstructure observations of HSFCM were carried out, and the strength and deformation characteristics, microstructure and composition evolution of HSFCM after high temperature treatment were discussed. After high temperature treatment, the compressive strength of HSFCM deteriorated. The compressive strength of HSFCM decreased by more than half at 400 °C. The peak strain increased at 200 °C with the increase of temperature, and decreased at 400~600 °C with the increase of temperature. High temperature reduces the stiffness of HSFCM, and the elastic modulus decreases with increasing temperature. The influence of high temperature on the microstructure of HSFCM is mainly shown in the increase and enlargement of pores in three-dimensional space, the development of micro-cracks and the thermal decomposition of cementing material into stable oxides without cementing effect. The microscopic changes of HSFCM are in good agreement with the mechanical test results.

Deformation analysis and control of underwater large-diameter shield tunnels is a prerequisite for safe tunnel construction. Reasonable selection of constitutive model and its parameters is the key to accurately predicting the deformation induced by underwater shield tunnelling. In this paper, the finite element analysis of cavity expansion during the piezocone penetration test (CPTU) based on the hardening soil model with small strain stiffness (HSS) model was carried out, and the correlation model of the normalized cone tip resistance Q with the reference secant modulus E50ref and the effective internal friction angle φ^’ was established and verified using mini CPTU chamber test. Then, a Bayesian probability characterization approach for E50ref of silty clay based on CPTU was proposed. Furthermore, the deformation analysis of Jinan Yellow River tunnel crossing the south embankment was carried out to verify the reliability of the proposed approach. The good agreement between the field measurement and numerical simulation confirms that the parameters obtained by the Bayesian approach are reliable. Finally, a sensitivity analysis was performed to study the law of riverbed settlement induced by underwater large-diameter shield tunnelling. The results show that the increasing support pressure could effectively reduce the riverbed settlement, but there is an upper limit. The optimal support pressure of established model is between 0.45 MPa and 0.5 MPa. The uphill section causes greater riverbed settlement than the downhill section. Under the same condition, increasing buried depth and water level will lead to a more significant settlement.