Granular soil

One-dimensional swell or settlement potential of cohesive soils California Bearing Ratio (CBR) of laboratory-compacted soils Bearing ratio of soils in place Permeability of granular soils by constant head pH of soil for use in corrosion testing... 

The MTG regulations require that granular soil drainage materials must5... 

To calculate the required flow rate, Q, in granular soil drainage designs based on MTG values ... 

In the design of granular soil (sand) filter materials, the particle-size distribution of the drainage system and that of the invading (or upstream) soils is required. The filter material should have its... 

The LDCR system is located between the primary and secondary liners in landfills, surface impoundments, and waste piles. It can consist of either granular soils (i.e., gravels) or geonets. 

U.S. EPA specifies that the minimum detection time for the leachate entering the LDS of an LDCR system is <24 h. Response time calculations are based on velocity in the geonet and/or granular soil drainage layer. Darcy s law is used to calculate flow velocity in the geonet, and a true velocity must be used for granular soil. 

Surface water drainage systems can be composed of granular soils, geonets, or geocomposites, but the majority of drainage systems use granular soil. This is particularly true in frost regions where it is necessary to have 3-6 ft of soil above the FML to satisfy the requirements for frost... 

In gas-collector systems, either a granular soil layer or a needle-punched nonwoven geotextile is placed directly beneath the LML or clay of a composite cap system. Gas compatibility and air transmissivity are the design factors that must be considered. Methane, the most predominant gas, should be compatible with most types of geotextiles including PET, PP, and PE. 

ASTM, Standard Test Method for Permeability of Granular Soils (Constant Head), ASTM D2434-68(2006), American Society for Testing and Materials, West Conshohocken, PA, 2006. 

Limited to granular soils and moderate to high solubility hydrocarbons... 

Fig. 2.2 Piston flow of water infiltrating into a homogeneous granular soil (sponge-type flow). A layered structure is formed, lower water layers being older than shallow ones. Penetration velocities are observed to range from a few centimeters to a few meters per year.

Originally, the v factor for medium commodities was 10. However, the residue workgroup of the York Conference recommended that the v factor be reduced to 7 for applications other than granular soil formulations. 

In a classic early study, Wollny (1881) reported that the CO2 content of the soil at 30 C increases about ten times as the soil moisture content changes from 6.8% to 26.8%. The CO2 content of soil air also increases with depth and the O2 content falls (Table 14-II). The gradient is influenced by the nature of the soil granular soils contain less than... 

Samples of soil from shallow depths can be obtained from holes or pits. In granular soils, holes and pits will cave unless the side slopes are less... 

Figure 2.1 is a pictorial representation of the void ratio. Void ratios for granular soils range from 0.4 to 0.8. Clays and clayey soils will range from 0.5 to 1.5 or 2.0. Soils with high organic content, peats and mucks, may have void ratios as high as 4 or 5. 

The shear strength of soil is made up of two separate components, cohesion and internal friction. Cohesion is related to grain size, and is apparent in clayey soils. Granular soils are not cohesive. Coulomb s equation is universally used to express shear strength ... 

It is generally assumed that for soft, saturated clays 4> is close to zero, and that for granular soils C is equal to zero. Thus, for ideal soils, shear strength can be approximately represented by straight lines on diagrams as shown in Figure 2.3. These lines are called failure lines, because a state of stress which would plot above them represents a failure condition. 

A partially saturated granular soil weighs 115 pcf in its wet condition, and has a 10% water content. Estimate the void ratio and porosity. How much would the soil weigh if it were fully saturated What would be its submerged unit weight ... 

Leonards, G.A. et al, Dynamic Compaction of Granular Soils, Journal of the Geotechnical Engineering Division, Jan. 1980, pp 35-44, ASCE, Reston, VA. 

Table 9.1 Approximate Guidelines to Groutability of Granular Soils and Rock when Particulate Grouts Are Used... 

Figure 10.7 (a) Failure lines for grouted and ungrouted granular soils, (b) Drained triaxial test results for silicate grouted coarse and medium sands. (From Ref. 11.15.) (c) Typical stress-strain curve from unconfined compression test on chemically grouted sand, (d) Compression versus time data for creep test on chemically grouted sand, under constant load, (e) Failure time versus percent of unconfined compression failure load. (+) indicates unconfined compression tests, and ( ) indicates triaxial tests with S3 = 25% of Si. 

If many flow channels are available and flowing, such as in the case of granular soils, or severely fissured rock, procedures are generally used which attempt to impermeabilize a predetermined volume of the formulation. These are discussed in Chap. 17. 

Granular soils have no unconfined strength and cannot be subjected to unconfined compression testing. To determine the shear strength of granular... 

Figure 18.1 Representation of shear strength of a granular soil.

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