Method for the rapid determination of soil physical parameters of extensive green roofs

Abstract

Optimization of soil mixes used for extensive green roofs is essential in a long-term, well-functioning system design and implementation. One of the key elements of this is determining the soil physical characteristics of the used components with the following critical elements: rock mass, rock volume, space between particles, water absorption and water retention capacity, surface water retention. In our research we developed a new method for rapid identification of soil physical performance characteristics of extensive green roofs. The performance indicators were divided into three groups: 1. density-related indicators: loose density, wet loose density, rock material density, wet density of the rock, crystal structure density, rock mass per unit rock volume; rock volume per unit rock volume, rock mass per unit wet rock volume, rock mass per unit wet rock mass. 2. Water content related indicators: water content (porosity) per unit mass of wet rock, water content (porosity) per unit wet rock volume, water content per unit volume of wet granules, surface water per unit volume of granules, surface water per unit mass of granules. 3. Indicators related to space between particles: space between grains per unit volume of granules, space between grains per unit mass of granules. During the development of the procedure and method it was important for us that the parameters should have been determined simply and easily. Further advantages of the developed method are that they are fast, cheap and reasonably accurate and help rock/soil mixture characterization and quantitative comparability. We illustrate the method and the system of performance indicators on examples of growing media mixes for extensive use.