High Performance Concretes in Production of Pre-Tensioned Concrete Hollow-Core Slabs in Poland

Abstract

Pre-tensioned concrete hollow core (HC) slabs have been used in construction for several decades. In Poland, industrial production has been carried out since the 1970's. Currently, due to the dynamic development of precast structures, these elements are gaining in popularity. The article describes the most important changes in the hollow core slabs fabrication technology in Poland within period of over 40 years. Modern elements have gained new features, high load capacity and high quality. The quality and repeatability of characteristics of the slabs is associated primarily with the use of new-generation concretes (with admixtures and additives). The paper describes and analyzes the most important differences related to the production of HC slabs currently, and the production from the 1970's and 1980's of the last century. The advantages and disadvantages of high performance concrete in the context of their application for production of hollow core slabs have been formulated and presented. The theoretical considerations were then extended by results of research carried out on full-scale elements. The analysis is supplemented with a calculation example of determining the bending capacity in commonly used cross-section of HC slab.