The hydro-seeding and concrete anchors as a method for preventing damage to district heating network by local landslides

Abstract

To prevent rain from eroding the sides of the trench we have developed a method of spraying them with hydro-seed. The homemade solution contains water, soil, mulch and a special blend of local grass seed. The mixture containing the blend of seeds enhances the soil to give it some strength and minimize the erosion. Another option is using concrete anchors instead of steel ones, which are supposed to increase the rigidity of a district heating (DH) network. The paper further visualizes the process with the materials required for each step. We constructed the equation in order to estimate net present value depending on the capital costs of the construction, the time of the cash flow, and the discount rate. In case of concrete anchors, the NPV of the project is negative. However, in case of hydro-seeding, the income provided by avoiding penalties becomes bigger than initial costs in the very first year of the project life span. From the comparison of two NPV profiles, the model combining the concrete anchors and the hydro-seeding can save up to 20% of investments compared to the conventional DH line. Results show that although then capital costs are increased by up to 24%, investment payback for DH network can be reduced to 12 years while life span can be increased by up to 30 years.