Manufacturing of Concrete Products and Precast Elements

The flexible use of prefabricated concrete products requires a continuously increasing diversity with regard to fresh concrete mix designs and properties, moulding processes, surface finishes and product characteristics.This trend imposes ever-higher requirements on manufacturers of the associated production equipment and on precast plants. The main goal is to implement a flexible production system in all processing stages. The relevant correlations and interactions need to be thoroughly considered and evaluated in order to ensure that concrete products and precast elements are manufactured to the required quality standard.To date, no comprehensive description of these correlations has been published in the relevant literature. This richly illustrated book closes the gap by describing the basic principles of the production processes, the fundamentals of materials, the composition of the concrete mix, and the equipment used for concrete production. Clearly arranged chapters detail the production processes and equipment used to manufacture small concrete products, concrete pipes and manholes, and precast elements.The authors have used their many years of experience in the field of precast technology and their close ties to the industry. Their aim was to integrate modern testing and calculation methods from neighbouring disciplines into precast technology. This includes, for instance, modelling and simulation of the workability behaviour of mixes, implementation of the latest advancements in machine dynamics to the design and engineering of production equipment, and the use of stateof-the-art measuring and automation technology for quality control purposes.

ForewordIntroduction1 Basic Principles1.1 Process Fundamentals1.1.1 Production Process1.1.2 Components Determining the Structure of the Production Process1.1.3 Processes for the Industrial Manufacturing of Concrete Products1.1.4 Processing Behaviour of Concrete1.1.5 Process Parameters1.2 Fundamentals of Materials1.2.1 Raw Materials for the Production of the Concrete Mix1.2.2 Concrete Mix Design and Composition1.2.3 Concrete Properties1.3 Product Fundamentals1.3.1 Concrete Products1.3.2 Requirements Relating to Product Characteristics andTesting Methods1.3.3 Evaluation of Conformity1.4 Fundamentals of Plant and Equipment1.4.1 Vibration Exciter Systems1.4.2 Research and Development2 Production of the Concrete Mix2.1 Mixing Facilities2.1.1 Star-shaped Systems2.1.2 Serial Systems2.1.3 Tower Systems 72.2 Mixers2.2.1 Pan Mixers2.2.2 Open-top Mixers2.3 Quality Control2.3.1 Assessment of the Mixing Quality2.3.2 Moisture Measurement2.3.3 Mixer Control3 Production of Small Concrete Products Overview3.2 Block Machines3.2.1 Technological Line3.2.2 Configuration of Block Machines3.2.4 Quality Control3.3 Egg Layers3.3.1 Scope of Use3.3.2 Configuration and Mode of Operation3.4 Slab Moulding Machines3.4.1 Scope of Use3.4.2 Configuration and Mode of Operation3.5 Production of Concrete Roof Tiles3.5.1 Casting Process3.5.2 Extrusion Process3.5.3 Quality Control3.6 Finishing and Post-treatment3.6.1 Finishing of Fresh Products3.6.2 Finishing of Hardened Products3.7 Selection Criteria4 Production of Concrete Pipes and Manholes4.1 Production Process4.2 Fabrication of Reinforcement4.3 Pipe Machines with a Stationary Core4.4 Pipe Machines with a Rising Core4.5 Roller-head Process4.6 Wet-cast Process4.7 Production of Manhole Rings and Bases4.8 Curing and Pipe Testing4.9 Quality Control, Characteristics of Defects4.9.1 Typical Pipe Defects and their Causes4.9.2 In-Process Quality Control4.10 Selection Criteria5 Production of Precast Elements5.1 Overview5.2 Basic Structure of Production Systems5.3 Carousel Production5.3.1 Basic Structure5.3.2 Subsystems5.3.3 Complete Production Lines using the Carousel Principle5.4 Stationary Production5.4.1 Basic Structures5.4.2 Subsystems5.4.3 Complete Lines for Stationary Production5.5 Combined Production5.6 Curing and Finishing5.6.1 Curing Systems5.6.2 Finishing5.7 Quality Control5.7.1 Design of Vibration Moulds5.7.2 In-Process Quality Control5.8 Selection Criteria6 Outlook7 Bibliography8 Index