The interaction of the steel shell and the core concrete element in operation

Abstract

Pipe concrete as a complex material, which effectively combines the advantages of steel and concrete, is used in the construction of high-rise and long-span structures and has good prospects for expanding the scope. At present, this is prevented by the relatively poor knowledge of the steel shell interaction with the concrete core under operational loads, when, due to the difference in the coefficients of transverse deformation of steel and concrete, the shell can detach from the core and lose its stirrup effect, which significantly increases the concrete strength. In the article in a linear-elastic formulation, the Lame problem is applied to a circular cylinder subjected to internal (for the shell) and external (for the core) uniform radial pressure, as well as an external centrally applied the longitudinal compressive force. The formulas for determining the stresses and radial displacements in the shell wall and core are obtained. The recommendations on providing the conditions for the joint operation of the shell and core, which are relevant, in particular, for the pipe-concrete kinematic racks of foundations protecting the buildings under seismic effects, are given.