Research on Construction Technology of Conversion Floor of Super High-rise Building Main Structure Based on Composite Beam Method

The construction of the transfer floor of the main structure has an important impact on the quality and safety of high-rise and super high-rise buildings, and the composite beam method plays an important role in this link of construction. Based on this, this paper combined with the construction case of 3500mm thick structural transfer floor of a super high-rise building in Puyang, studied the application points and performance improvement effect of composite beam method. Compared with the conventional method, the peak temperature in the core area of the structure is controlled at 60.7~63.5 ℃, which is lower than the early warning threshold of 75 ℃, and the safety margin is 11.5~14.3 ℃; The maximum temperature rise is 36~40 ℃, which is lower than the critical standard of 45 ℃, and 5~9 ℃ lower than the conventional method; The extreme temperature difference between the inside and the surface, the surface and the environment is ≤ 24.6 ℃, which is lower than the control standard of 30 ℃, which is 5.4~6.2 ℃ lower than the conventional method, and the hydration heat effect is effectively suppressed. The 28d concrete strength is 1.2~1.4 times of the design grade, 26% higher on average, and the structural bearing capacity is significantly improved. After 60 days of pouring, there was no obvious crack in the transfer floor and floors 1-7, and the temperature crack prone to occur in the conventional thick plate transfer floor did not occur, and the crack resistance was significantly improved. The practice shows that the composite beam method can effectively solve the key problems such as load transfer, hydration heat control and cracks in the construction of thick plate transfer floor, and the construction safety and structural quality can be quantitatively improved compared with the conventional method.