Porosity and durability tests on 3D printing concrete: A review

3D concrete printing represents a modern trend in construction automation, characterized by the layer-by-layer deposition of concrete using 3D printers to construct structures without traditional formwork. This process alters the rheological behavior, microstructure, mechanical properties, and durability of 3D-printed concrete compared to conventional cast concrete. This review outlines the porosity and durability tests conducted in previous research papers. It presents the details and procedures of these tests, along with any referenced standards or guidelines. By comparing printed specimens to cast specimens, both similar and controversial results from the tests are also comprehensively discussed. It becomes evident that the durability properties of printed specimens differ from those of cast specimens due to their distinct pore systems. Ultimately, this review aims to bridge research gaps in 3DPC durability performance and assist in the selection of methodologies for porosity and durability tests.