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From the analysis of the production process of molded pulp packaging, it can be seen that one of the residues generated in the molding is “pulp”. When this waste cannot be reincorporated into the production line, is recovered by centrifugation in the effluent treatment system. With the intention of recycling this residue it was investigated the feasibility of their use in the manufacture of concrete blocks or panels lightened studying possible ways to use the material, either in the wet state (form is discharged from the process) or dry (dried in a controlled environment), analyzing the advantages and disadvantages of each alternative. For practical purposes, various dosages were proposed to maintain constant the amount of residue and varying the amounts and proportions of water and cement. Test specimens were made with various amounts of cement per m 3 of concrete. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a systematic approach for the experimental testing and analysis of the early-age thermo-mechanical behaviour of large prismatic high-performance concrete specimens under restrained autogenous shrinkage and realistic temperature conditions. The loading system can apply a partial degree of restraint in order to enable the characterisation of high-performance concrete specimens without premature termination of the test in case of significant restrained shrinkage. The instrumentation system can measure the strains and other parameters from the setting time with high accuracy and reliability. The analysis method takes into account the temperature effects on the measured properties and provides equations to determine the time-evolution of shrinkage, thermal expansion, stiffness and creep of the concrete. Results from the testing of 200×200×1000 mm specimens made with a 0.34 water–cement ratio concrete are presented, analysed and discussed in the paper to demonstrate the application of the proposed approach. [Copyright &y& Elsevier]

Abstract: To solve the problem of the waste generated by the natural stone industry, several technical solutions consider the incorporation of this type of waste in other industrial activities as a by-product. This paper presents an overview of current solutions and the results of a research project where natural stone slurry is used to replace fine aggregates in concrete mixtures. The concrete mechanical properties are presented and the technical viability of this new construction material is illustrated. [Copyright &y& Elsevier]