Content introduction 1.1 Project background The title of this project is the comprehensive office building of Bank of China Zhengzhou Branch, which is a 6-storey reinforced concrete frame structure system, covering an area of about 1089.02m2, with a total construction area of about 6474.13 m2; The floor height is 3.9m, and the plane size is 54.94 × 19.44m. The independent foundation is adopted, the indoor floor is ± 0.000m, and the outdoor and indoor elevation difference is 0.6m. Frame beams, columns, floors and roof slabs are cast-in-situ. 1.1.1 Design data meter 1. The natural unit weight of foundation soil index is 1.90g/cm2, the liquid limit is 25.5%, the plasticity index is 9.1, the void ratio is 0.683, and the calculated strength is 150kp/m2. 2. Geological conditions The building site is flat, and the foundation soil is of glacial proluvial origin. The description from top to bottom is as follows: recent sedimentary layer (the first layer), silty clay, thickness 0.5-1.0m, lithological characteristics, agglomerated large pore structure, under compaction. Silty clay layer (the second layer), the main geological lithology is yellow brown clay, hard plastic state, with a large pore structure, thickness of about 3.0 meters, qsk=35-40kPa. Silty clay layer (the third layer), the geological lithology is brown yellow silty clay, with micro bedding, containing ferromanganese nodules, plastic state, thickness of 3.5 meters, qsk=30-35kPa. Silty clay layer (the fourth layer), lithology is isabelline silty clay, with micro bedding, iron and manganese nodules, hard plastic state, thickness not exposed, qsk=40—60kPa,qpk=1500—2000kPa。 Groundwater is not considered. 3. Meteorological data The highest temperature is in summer, and the lowest outdoor temperature is in winter. The depth of frozen soil is 25cm, and the basic wind load is W= 0.4kN/ m2; The basic snow load is 0.2 kN/m2. The annual precipitation is 680mm.