The researchers studied how excess water pressure in soft clay changes under different conditions. They did tests with and without pressure to see the effects of stress, frequency, and pressure. They found that higher stress leads to more water pressure, but higher frequency reduces it. More pressure increases the maximum water pressure, but not the minimum. Also, higher stress and pressure make the water pressure change faster. The rates of water pressure change over time are the same no matter the frequency. The researchers made models to predict maximum and minimum water pressure based on these factors, and the predictions matched the actual results.