Influence Of Saltwater Concentrations On Mechanical Properties Of Foamed Concrete

Several billion tons of water is annually used as mixing,curing and cleaning around the world,in concrete industry.As there is a scarcity of fresh drinkable water around the world;so,there is a need to save fresh water and hence possibilities of using saltwater as mixing as well as curing water should be investigated seriously.Additionally,if use of saltwater as a foam concrete material is permitted,it will be very convenient and economical in the especially in the coastal works.The effect of saltwater on concrete deserves special attention as the coastal and offshore structures are exposed to simultaneous action of a number of physical and chemical deterioration processes.Moreover,80 percent of the earth is covered by saltwater either directly or indirectly(e.g.winds can carry saltwater spray up to a few miles in land from the coast).Concrete piers,decks,break-water,and retaining walls are widely used in the construction of harbors and docks.The use of concrete offshore drilling platforms and oil storage tanks is already on the increase.The search shows that the research of saltwater of foam concrete has not been reported.Foam concrete contains a large number of small,closed bubbles,due to its unique structural characteristics,with light,thermal insulation performance,high fire resistance,good seismic performance,environmental protection and other advantages,in the industrial,civil construction,municipal engineering,the field has been widely used.Considering the characteristics of lightweight and durability of foamed concrete,it is often used as the enclosure structure of the slope of the Ocean harbour,and because the foam concrete has the characteristics of absorbing the damping wave,it can be used in the offshore drilling platform with foam concrete to relieve the impact and damage of the bit on the platform.With the development of foam concrete,the application of the field of marine engineering is increasing.The South China Sea has a 180 many unmanned islands,the island’s less rainfall,evaporation,high dryness,which caused the uninhabited islands extremely lack of freshwater.In order to get local materials and quickly realize the residence condition of the island,this experiment partially or totally replaces fresh water with salt water to explore the effect of saltwater concentration on the mechanical properties of foamed concrete.The test consisted of three water-cement ratios of the test pieces: 0.5,0.6 and 0.7.The brines were 0%,50% and 100%.The relevant compressive strengths,splitting strengths,dry densities,and water absorption rates were measured for the relevant 3,7,14 and 28 days.And also cracking test was done by this experiment and found out the increase of w/c ratio from 0.5 to 0.6 and 0.7the average cracking time of salt water and fresh water of foam concrete are decreased,it can also be seen a slight difference of the cracking time is a little.Therefore,using fresh water or saltwater is almost similar.The result shows that the salt water will reduce the relevant strength indicators,but compared to freshwater conditions,the decline in saline conditions is about 3-8%.This shows that in the absence of fresh water,Saltwater can be considered as an alternative to freshwater.The salt water foam concrete proposed in this paper is a new research.