The determination of the consistency (condition) can be done both in situ and in the laboratory. In the case of the in-situ test, the condition of a cohesive type of soil is to be determined as follows:

1. A type of soil is called “very soft, if it runs through the fingers while being pressed together in a fist;

2. Soft, if it can be kneaded easily;

3. Firm, if, although it is hard to be kneaded, it can be rolled out to 0.12 in (3 mm) thick rolls in the …

Soil plasticity is the “Property of a cohesive soil, which changes its mechanical behaviour with change in the water content” [DINENISO14688:2001].

The plasticity is the range between the liquid- and the plastic limit. This range is classified into very soft, soft and firm [DIN18122].

(Image: Consistency band [Trian00])

The state conditions of the plastic range are shown as numerical values ​​in the table. The liquidity index I_L = 1 - I_C is also listed.

(Table: Conditions in the plastic range [DIN18122])

(Image: Plan view of water catchment area [Schil86])

In DIN 4046 [DIN4046], a water catchment area is defined as follows:

"A catchment area or a part of a catchment area of a water gathering installation that is subject to the protection of water utility limitation."

According to the DVGW working paper W 101 [DVGWW101], the water catchment area is usually divided into 3 protective zones:

• Zone I : Collection region (Abschnitt 6.3)
• Zone II : Inner protected …

(Image: Water distribution on Earth)

“Water is essential for achieving sustainable development and the Millennium Development Goals. Properly managing water resources is an essential component of growth, social and economic development, poverty reduction and equity – all essential for achieving the Millennium Development Goals” [Unesc].

From a chemical point of view, water (H₂O) is a compound consisting of two hydrogen atoms (H) and one oxygen atom (…

According to [DIN4049-3], the hydrologic cycle is the permanent changing of water in its state and location, with its main components being precipitation, runoff, evaporation and atmospheric transport of water vapour.

In other words, the hydrologic cycle describes the continuous transport and storage of water on both a global and regional level, above and below the Earth’s surface. In the process, the water changes its aggregate state several times …

The hydrologic balance equation (in general also called water inventory or water budget equation) is a quantitative description of the natural hydrologic cycle, i.e. the interrelation between the components and environmental compartments of water (hydrosphere), soil (pedosphere) or air (Earth’s atmosphere).

The components are:

• Precipitation: According to [DIN4049-3], it is described as “water that is bound to the atmosphere as a result of the condensation …

The regional hydrologic cycle is in a small way also influenced by the “urban hydrologic cycle” that is shaped by man. The mere development of urbanisation (the spread of the urban lifestyle) has a massive influence on the water balance and results in both quantitative and qualitative changes of the units to be balanced in the catchment area under observation. According to [Klinger2007], the main anthropogenic activities with negative effects on …

The proper functionality and leak-tightness of the drain and sewer system has a massive impact on the hydrologic cycle in urban areas, and thus also on both the quantity and quality of groundwater as a resource. Combined with the effects of the global climate change (global warming, climatic shifts), this fact becomes a national challenge. What is important in this context is to realise that due to the very distinct local and environmental conditions …

Soil explorations, that are to be carried out to the required extent and then to be appropriately evaluated, form the basis for the structural calculations of already existing, newly to be laid, or to be rehabilitated drains, sewers and associated structures by means of the open cut or trenchless method of construction.

For these applications, [[ASTM D2487-06]] classifies the types of soils as follows:

• Category I: Clean, course grained soils: SW, …

For the design of sloping or benching systems, the Occupational Safety and Health Administration (OSHA) classifies soils from excavation operations as presented in the table below.

The soil classification, according to [[OSHA 29 CFR 1926 Subpart P App A]], are based on the definitions in whole or in part, the following; American Society for Testing Materials (ASTM) Standards D653-85 and D2488; The Unified Soils Classification System; The U.S. Department …

The table below presents the classification of non-cohesive soils for engineering purposes based on particle size, coefficient of uniformity (C_u) and coefficient of curvature (C_c) [[ASTM D2487-06]].

(Table: Non-cohesive soil classification as per ASTM D2487)

The following table presents classification of cohesive soils for engineering purposes based on particle size, coefficient of uniformity (Cu) and coefficient of curvature (Cc) [[ASTM D2487-06]]. Cohesive soils do not crumble, are hard to break up when dry and include clayey silts, sandy clays, silty clays, and clays.

(Table: Cohesive soil classification as per ASTM D2487)

Organic soils are classified as per [[ASTM D2487-06]] according to the table below.

(Table: Organic soil classification as per ASTM D2487)

Organic fine-grained soils have a 50% or more passing rate through a No.200 sieve. Organic clays and organic silts are soils that would be classified as clay or silt, except that their liquid limit values after oven drying is less than 75 % of their liquid limit value before oven drying [[ASTM D2487-06]].

The table below presents a classification of organic fine-grained soils (OL and OH).

(Table: Classification of organic fine-grained soil (50% or …

A simpler differentiation is done in European standard [DINENISO14688:2004].

This standard differentiates soils based on soil type, designation and grain size.

(Table: Soil type and grain size fractions as per EN ISO 14688-1)

The main aim of The American Association of State Highway and Transportation Officials (AASHTO) and the Federal Highway Administration (FHWA) soil classification system is to have a system appropriate for highway sub-grade materials based on their performance. The AASHTO System has seven soil classes including A-1 to A-7. The soil is placed in the classes based on performance characteristics. A-1 is the highest and A-7 is the lowest. A-1 to A-3 are …

Terzaghi at 1950 for the first time provided the Tunnelman’s Ground Classification system which became famous as a common and functional tunneling classification of soft ground, and later Heuer in 1974 refined it. Tunnelman’s Ground Classification System was designed to explain different ground performances and their effect on larger, conventionally constructed soft ground tunnels. This system is also a powerful tool to evaluate the soft ground conditions …

This page presents the assignment of different soil types to three compactibility classes based on German standards. As per ASTM, non-cohesive to cohesive soils as well as coarse-grained and mixed soils (sand and gravel) have good compactibility characteristics.

(Table: Compactibility class V1 to V3 as per ZTVA-StB 97)

In this context, the tabular information on the classification of soils for civil engineering purposes in this (→ Table: Soil classification …