Additive concrete manufacturing processes are sensitive to process settings and conditions, which calls not only for preprint structural modelling to establish printability, but also for in-print monitoring to ensure expected properties are indeed achieved.
Most construction materials such as steel, concrete, aluminum and plastic require a high energy input during the manufacturing process while the manufacture of timber products uses much less energy than the competitive materials.
Of course, we could debate if "zero" is even good enough, since cutting-edge sustainability thinking focuses on creating products that improve the environment (such as concrete that captures CO2 in its manufacturing process or building materials that clean the air).
Chopped basalt fibre has recently gained popularity in concrete reinforcing applications due to its environmentally friendly manufacturing process and excellent mechanical properties.
If a specific sample achieves the established correlation threshold, this would indicate that the concrete admixture has not been altered during the manufacturing process or storage prior its use.
Using these mixes, a total of ninety prestressed concrete sleepers were produced in a factory under the same manufacturing process as current railway sleepers, and their mechanical properties as well as durability performance were evaluated.
This level of discrepancy can be attributed to the uncertainty of channel spacing, which influences significantly the pressure losses and for which unfortunately no concrete measurements can be made, owed to no actual access to the plate manufacturing process itself.
Trials in the laboratory successfully replicated the manufacturing process using a specially modified electric hammer drill to compact the concrete mix into oversize steel moulds to produce blocks of the same physical and mechanical properties as the commercial blocks.
In contrast, steel and concrete use more energy, emit more greenhouse gases, and release more air and water pollutants during the manufacturing process than that of wood products (APA 2017).
Open image in new window Fig. 16 Manufacturing process of the PSC curved bridge: a Formwork assemblage, b rebar assemblage, c side jack control, d concrete casting, e steam curing, f prestressing, g girder lifting, h cross beam rebar, i cross beam concrete casting, j deck rebar, k deck concrete casting, l finished bridge.
