Soil weight volume relationships. CEEN 341 2019-03-05

Soil weight volume relationships Rating: 9,9/10 1659 reviews

Weight

soil weight volume relationships

In addition, in many agencies, the group responsible for determining the environmental inputs is poorly defined, and thus this responsibility may end up with the geotechnical group. Coarse particles are defined as larger than 0. For example, D 10 is the largest particle size in the 10% finest fraction of soil; D 60 is the largest particle size in the 60% finest fraction of soil. If the soil contains a substantial amount of fibrous organic materials, these may tend to plug the sieve openings during washing. The weight and volume of a soil sample depends on the specific gravity of the soil grains solids , the size of the space between soil grains voids and pores , and the amount of void space filled with water moisture content and degree of saturation. It has a low relative density, a low unit weight, and a high void ratio.

Next

Weight

soil weight volume relationships

The comparison of these two figures clearly shows that the higher quality Level 1 material inputs dramatically reduce the variability between predicted and observed cracking. Other required inputs include geometric information like layer thickness, but these are generally self-explanatory and are not discussed here. A simple way to determine whether sieves should be replaced is the periodic examination of the stretch of the sieve fabric on its frame. . This is understandable given the inherent differences between mechanistic-empirical and empirical design methodologies. This level might be used for designs in which there are minimal consequences of early failure e. Therefore, it is unlikely that a single descriptive theory can include them all.

Next

Physical Properties of Soil

soil weight volume relationships

However, under heavy load or when subjected to shock loading, the structure breaks down, resulting in large settlement. The type of absorbed ions will effect the plasticity characteristics such as Na , Mg will give high plasticity while Ca will give low plasticity. The material settling over the sieve during washing should be constantly stirred to avoid plugging. Loess, unlike other non-cohesive soils, will stand on almost a vertical slope until saturated. Alternatively, after the specimen is inundated, the height of the specimen is kept constant by adding loads. Predictions of thermal cracking were made based on these Level 1 material inputs as well as on Level 3 default material properties.

Next

CEEN 341

soil weight volume relationships

A one-dimensional swell potential test is used to estimate the percent swell and swelling pressures developed by the swelling soils Table 5-23. Montmorillonite smectite exhibits a high degree of swell potential, illite has negligible to moderate swell characteristics, and kaolinite exhibits almost none. Swell potential also depends on the mineralogical composition of fine-grained soils. In both cases, disturbed samples obtained from these deposits will be classified as silt. Commentary Obtaining a representative specimen is an important aspect of this test. One consequence of all of the above is that this chapter is quite long; this is necessary to give sufficient coverage to all of the diverse geotechnical inputs required by the two design procedures.

Next

Chapter 5

soil weight volume relationships

At high moisture contents, these soils collapse and undergo sudden decreases in volume. Common terms associated with weight-volume relationships are shown in Table 5-7. These inputs are usually provided by agency units other than the geotechnical group. Shape and size of grains. As described in Chapter 3, there may be other geotechnical issues e.

Next

Weight

soil weight volume relationships

Gradation is occasionally expressed alternatively in terms of the percent coarser than a given grain size. Honeycombed structure In this structure, relatively fine sand and silt form small arches with chains of particles as shown in the figure below. The geotechnical inputs required for rigid pavement design using the 1993 Guide are summarized in Table 5-2. Collapsible soils exhibit abrupt changes in strength at moisture contents approaching saturation. This level could be used when resources or testing equipment are not available for Level 1 characterization.


Next

Physical Properties of Soil

soil weight volume relationships

A representative sample is washed through a series of sieves Figure 5-5. The first five properties in Table 5-2 are used to determine the effective modulus of subgrade reaction k in the 1993 Guide procedure. This property is called dilatancy. However, the higher level inputs implicitly increase the accuracy and reliability of the predicted pavement performance. As we will describe later the characteristics of each type of clay mineral group the type will effect the plasticity characteristics and for instance 4. Commentary This test can be performed on undisturbed, remolded, or compacted specimens.

Next

Chapter 5

soil weight volume relationships

For a gel system, agitation disrupts the three-dimensional structure that binds the system into a gel. Gradation is measured in the laboratory using two tests: a mechanical sieve analysis for the sand and coarser fraction Table 5-19 , and a hydrometer test for the silt and finer clay material Table 5-20. The unit weight, y, can be computed using one of the following relationships: This expression for unit weight makes no assumption about the amount of water present in a sample of soil or rock, and is based simply on the weight and volume of the soil or rock. The principal physical properties of interest are specific gravity of solids, water content, unit weight density , gradation characteristics, plasticity Atterberg limits , classification, and compaction characteristics. Although it is intuitively clear that higher level i.

Next