Plant Growth and Water Purification of Porous Vegetation Concrete Formed of Blast Furnace Slag, Natural Jute Fiber and Styrene Butadiene Latex

Abstract

Abstract:The purpose of this study is to investigate porous vegetation concrete formed using the industrial by-products blast furnace slag powder and blast furnace slag aggregates. We investigated the void ratio, compressive strength, freeze-thaw resistance, plant growth and water purification properties using concretes containing these by-products, natural jute fiber and latex. The target performance was a compressive strength of ě12 MPa, a void ratio of ě25% and a residual compressive strength of ě80% following 100 freeze-thaw cycles. Using these target performance metrics and test results for plant growth and water purification, an optimal mixing ratio was identified. The study characterized the physical and mechanical properties of the optimal mix, and found that the compressive strength decreased compared with the default mix, but that the void ratio and the freeze-thaw resistance increased. When latex was used, the compressive strength, void ratio and freeze-thaw resistance all improved, satisfying the target performance metrics. Vegetation growth tests showed that plant growth was more active when the blast furnace slag aggregate was used. Furthermore, the use of latex was also found to promote vegetation growth, which is attributed to the latex forming a film coating that suppresses leaching of toxic components from the cement. Water purification tests showed no so significant differences between different mixing ratios; however, a comparison of mixes with and without vegetation indicated improved water purification in terms of the total phosphorus content when vegetation had been allowed to grow.

Performance Evaluation and Field Application of Red Clay Green Roof Vegetation Blocks for Ecological Restoration Projects

“…In addition, coarse aggregates may also be replaced with blast furnace slag aggregates. Blast furnace slag aggregates have a high moisture absorption rate and a high surface void ratio [9,15,16]. This study evaluated the use of concrete vegetation blocks and direct application of artificial vegetation soil.…”

“…To improve on this method, studies and developments on roof vegetation have mainly focused on the weight reduction of permeable layers and soil [8,11]. Recently, porous vegetation concrete has become ecofriendly, since it reduces CO2 emissions from cement production by replacing some cement with blast furnace slag fine powder and red clay, thereby recycling industrial byproducts [12][13][14][15][16][17][18]. The vegetation concrete is a porous material that encourages the growth of plants by introducing nutrient-containing water into voids [12][13][14][15][16][17][18].…”

“…The vegetation concrete is a porous material that encourages the growth of plants by introducing nutrient-containing water into voids [12][13][14][15][16][17][18]. Due to soil compartments on the porous concrete surfaces, there is space for germination, drying, and even fertilizer supplies after plant germination [12][13][14][15][16][17][18]. The use of porous vegetation concrete is depicted in Figure 1.…”

“…The use of porous vegetation concrete is depicted in Figure 1. The required properties of vegetation concrete are that plants can grow inside the concrete in accordance with the basic mechanical properties of concrete [12][13][14][15][16][17][18]. In addition, coarse aggregates may also be replaced with blast furnace slag aggregates.…”

“…Recently, porous vegetation concrete has become ecofriendly, since it reduces CO2 emissions from cement production by replacing some cement with blast furnace slag fine powder and red clay, thereby recycling industrial byproducts [12][13][14][15][16][17][18]. The vegetation concrete is a porous material that encourages the growth of plants by introducing nutrient-containing water into voids [12][13][14][15][16][17][18]. Due to soil compartments on the porous concrete surfaces, there is space for germination, drying, and even fertilizer supplies after plant germination [12][13][14][15][16][17][18].…”