The brick walls of ancient buildings have got a lot of tiny and closely connected pores inside, so they can soak up water really well. This can easily cause problems like getting powdery and having efflorescence. To stop water from spoiling the grey bricks, this paper focuses on the brick walls of historical buildings in Kaifeng City. Based on our investigation, we study the distribution features of the problems. This paper tells about using the method of negative pressure infiltration to change the grey bricks. We measure all kinds of basic indicators and analyze how different ratios of modifiers affect the water properties and dry-wet cycle tests of the grey bricks. We look at the changes in the inside shape through SEM to show how it changes the grey bricks of ancient buildings. Second, we improve the wet walls by using a way that combines blocking and drainage. The main things we studied and the conclusions are like this: We use sodium methyl silicate and acrylamide polymer as modifiers to soak the historical grey bricks under negative pressure. We figure out the best ratio through orthogonal experiments. We analyze things like the water vapor permeability, how long it takes for a water drop to go through, the compressive strength, the water absorption rate, and the height of water absorption of the modified bricks. The results show that the crosslinking agent and acrylamide monomer have a big influence on how high the capillary water goes up in the modified bricks. The air permeability of the modified grey bricks with acrylamide polymer goes down a bit, but it's still okay. The surface of the modified grey bricks is very hydrophobic and there are fewer pores inside. The mechanical properties of the modified grey bricks get better in different degrees. The water absorption rate and the height of capillary water absorption go down. The modified grey bricks can really cut down the erosion of water on the wall when used in real life. They can reduce salt crystallization and efflorescence caused by rising water, and so make the brick walls of historical buildings last longer. This is super important for protecting historical buildings in Kaifeng City and taking care of other similar structures. Also, by using a way that combines blocking and drainage, and putting polymer infiltration reinforcement and the ventilation of the moisture drainage pipe together, the results show that this combination can really lower the height that capillary water goes up in the brick wall. So we get a way to control how wet the wall is.
Suction caisson is a new offshore wind power foundation structure developed in recent years. Understanding its penetration characteristics is crucial to the successful application. A field test was conducted in the eastern waters of Rudong, Jiangsu Province, China, to investigate the penetration process of suction caisson. The test results demonstrate that suction caisson can penetrate smoothly to a predetermined elevation of seabed soil under the complex environmental loads, such as natural wind and wave currents. The inclination of the caisson is only 0.018 degrees degrees once the penetration process is complete. The pore water pressure at the outer skirt is primarily influenced by the tide level and drainage conditions of the contact soil layer during penetration, and the peak effective interface pressure at the skirt-soil interface decreases by about 46.7% due to negative pressure inside the skirt. Frictional fatigue effects are found at the skirt-soil interfaces. Meanwhile, the seepage reduction and squeezing induced resistance effects at the skirt-soil interface are the leading causes for the different distributions of effective interface pressure between the inner and outer skirts of the caisson. The findings of this study can guide the future penetration of suction caisson under challenging geological circumstances.