Discussion on Calculation Method of Soft Soil Foundation Settlement in Guangdong-Hong Kong-Macao Greater Bay Area

The modulus of compressibility of muddy soil in Dawan District is low, and the equivalent value of modulus of compressibility within the calculated depth range of foundation settlement is generally less than 2.5MPa, which exceeds the value range of empirical coefficient calculation basis for settlement calculation in the specification, and has the characteristics of large settlement. This time, according to the measured data of a coastal foundation settlement in Dawan District, the maximum settlement is fitted with the hyperbolic method, and the theoretical value of the total settlement is calculated according to the Code for Design of Building Foundation (GB50007-2011). Based on this analysis, the fitting curve equation of the empirical coefficient of settlement calculation when the equivalent value of the compression modulus is 2.5~4.15MPa is given, and the recommended value of the empirical coefficient of settlement calculation when the equivalent value of the compression modulus is 1.5~2.5MPa is calculated, so as to improve the calculation deviation of the original formula

The influence of soft clay saturation characteristics on unconfined compressive strength in Guangdong-Hong Kong-Macao Greater Bay Area

In order to study the influence of saturated characteristics of soft clay on unconfined compressive strength, the soft clay of Guangdong-Hong Kong-Macao Bay Area is taken as the research object, comparing and contrasting on unconfined compression test of saturated clay and unsaturated clay in laboratory, studying the variation law of unconfined compressive strength and sensitivity of unsaturated and saturated soft clay. The test results show that: 1. During the failure of unsaturated soft clay samples, oblique fractures appear, showing brittle shear failure, while the saturated clay samples appear constant bulging in the middle, and finally a “cross” is broken in the central bulging part, showing plastic shear failure.2. The unconfined compressive strength of unsaturated clay is about 10kPa higher than that of saturated soft clay, and its corresponding sensitivity is also about 0.4 higher. It can be shown that the soil saturation has a certain influence on the soil strength. The difference between saturated soil and unsaturated soil is the existence of gas phase. To be more precise, the existence of gas phase in unsaturated soil, i.e. the existence of suction, makes the soil stronger and presents the brittle shear failure form, while the saturated soil basically presents the plastic shear failure form