Experimental Study Of Concrete Lateral Pressure On Formwork

Concrete is one of building materials which is largest and most widely used in the world. Based on previous studies, the lateral pressures of concrete formworks are experimentally studied in the paper. The content of tests include the lateral pressures of concrete corresponding to different slumps and those corresponding to different sizes of concrete formwork. Experimental results show that within the effective range of vibration effect, the lateral pressures do not change with the slumps, which are basically equivalent to the hydrostatic pressures. However, after the vibration, the greater the slump, the slower the rate of decline of the lateral pressures. The size effect of the formwork manifest that the greater size of the formwork will lead to the greater values of the lateral pressures. There are two different test patterns and equipments adopted in the experiments. One is the formwork with small stiffness and the corresponding strain measurement system which can reflect the variations of the lateral pressures, however lead to large errors between the measured values and theoretical values and therefore should be used with caution. The other is the formwork with big stiffness and the corresponding strain measurement system which is complex in installation, but produce a small error between the measured and theoretical values and hence can be selected according to experimental purposes.