Mechanical Behavior of Compression-Compacted Dry Concrete Paver Blocks Making Use of Sea Sand and Seawater

Abstract

Dry concrete is a kind of concrete whose fresh mixture has almost no flowability and is widely used in the production of small-size unreinforced compression-compacted concrete blocks in plants. Considering the shortage of natural river sand and freshwater for concrete production, this study proposes that sea sand and seawater can be directly used in the manufacture of compression-compacted dry concrete paver blocks. The idea was verified in the laboratory to find suitable mix proportions and forming pressure, which are two key parameters for the production of paver blocks. Furthermore, the effect of sea sand replacement ratio and seawater replacement ratio is investigated, where compression and flexural tensile tests were conducted on lab-made paver blocks at different ages. The experimental results reveal that both the compressive and flexural tensile strengths of paver blocks increased when sea sand and seawater were adopted. It is finally suggested that sea sand and seawater are suitable for the production of unreinforced paver blocks with enhanced mechanical performance.