Integrated Techniques For Shear-Wall Frame Structure With Large Longitudinal Length Without Temperature Joint

Temperature and shrinkage stress of structures with large longitudinal and transverse lengths are one of the key problems in civil engineering, especially to that of shear-wall structures, where the rigid lateral stiffness of shear-walls would cause tensile stress while temperature decreases and concrete shrinks, hence would be easily to generate cracks that would reduce the serviceability of the structure. Correspondingly, this paper, taking the Sickroom Building of Yancheng First People's Hospital as example, analyzed the tensile stress caused by concrete shrinkage and temperature decreasing, and put forward a series of techniques to control the cracking. The paper mainly involves the following aspects:1. Discussed the concept and correlated factors of cracking in concrete structure, and the differences between cracks caused by direct and indirect actions are also involved.2. Carried out qualitative analysis of the stress while temperature decreasing and concrete shrinkage happened to the Sickroom Building of Yancheng First People's Hospital, and took both ANSYS and PMSAP as analyzing tools for comparison.3. Based on the above mentioned, a series of techniques, including reducing the constraint, concrete shrinkage and equivalent temperature variance, prestressing the floor slab to balance the tensile stress caused by temperature deformation, etc, were set up to control the cracking of the structure.4. Post-poured strip was used to enhance the prestressing effect, and the effectiveness of sectional stretching and integral stretching were analyzed and compared.5. Verified the distribution regularity of temperature stress and shrinkage stress and effectiveness of the above techniques by stress detecting during and after construction.