Study on Long-Term Performance of Concrete Based on Seawater, Sea Sand and Coral Sand

Abstract

Experimental studies of the long-term performance such have been done in this paper for sea water and sea-sand concrete and sea water and coral sand concrete, such as the elastic modulus, frost resistance and corrosion of reinforcement behavior. The test results show that the compressive elastic modulus of the sea water and sea sand concrete and the sea water and coral sand concrete are slightly lower than that of ordinary concrete, while the adding of fly ash or ground slag in them lead the late compressive elastic modulus slight increase. Compared with the ordinary concrete after freeze-thaw cycle, the mass loss rate and the compressive strength loss rate of the sea water and sea sand concrete and coral sand concrete are slightly larger, but slightly reduced by mixing with ground slag in the concrete, while a little high by mixing with fly ash. Due to the presence of Cl- in the saltwater and sea sand concrete and coral sand concrete, [Cl-] / [OH-] values will be larger, which leads to corrosion of internal reinforced, so it is necessary to adopt appropriate ways to modification for the concrete and reinforced.

Carbonation of concrete made with dredged marine sand and its effect on chloride binding

“…There are many studies on concrete carbonation and the effects of chloride on concrete durability [8][9][10][11][12][13][14]. Carbonation can reduce the pH of concrete and influence the stability of the bound chloride ions [15,16]. The chloride ions critical threshold is directly related to many factors, such as the chloride ions concentration and pH [1].…”

Study of Hydration and Microstructure of Mortar Containing Coral Sand Powder Blended with SCMs

“…The investigations on the mix proportion, physical and mechanical properties, and durability especially in chloride permeability and rebar corrosion of coral concrete were carried out [ 5 , 6 , 7 , 8 ]. Research results show that coral concrete has lower compressive strength, higher porosity, larger shrinkage, and poor corrosion resistance compared to conventional cement concrete [ 5 , 6 , 7 , 9 , 10 , 11 , 12 ].…”

The Study on the Whole Stress–Strain Curves of Coral Fly Ash-Slag Alkali-Activated Concrete under Uniaxial Compression

“…In 2012, Lei [ 56 ] found that CPC and lightweight aggregate concrete (LPC) have similar characteristics in strength development, failure mechanism and failure performance. In 2013, Yingtao [ 57 ] studied CPC and OPC with the same mix ratio and the performance differences in frost resistance and corrosion resistance. They found that fly ash or slag can be added to CPC to improve its freezing and corrosion resistance.…”