Dry Density

Compaction is a substantial parameter in geomechanics, and can be determined by using “Hilf” method. This method determines water content ratio using equations; hence oven is not required. Thereby the time which is needed to dry soil has been eliminated. The test needs 3 points for determining optimum Compaction and water content ratio. Experimental data must initially be accumulated for particular soil in order that the moisture variation can be reliably assessed. In this research “Hilf” method is performed in laboratory using CH clay obtained from Sarcheshmeh mines and sand. Purpose of investigation is to introduce method and to compare its accuracy with usual Proctor Method. Results show that accuracy of Hilf method is more than 99% in both clay and sandy clay.

Density is defined as the weight of soil per unit volume of soil. Often in the construction of different types of structures in-situ 'fill' is required. In-situ measurement of density is vital for such projects. When soil is being used as fill material it is usually compacted to a dense state to obtain satisfactory engineering properties. Dry density of soil basically depends on many properties of soil. For this reason it is difficult to establish an empirical relationship between electrical resistivity and dry density of soil. For similar type, grain size distribution and dry density of soil electrical resistivity widely various with different percentages of water. In this study dry density of soil was determined using standard proctor test. After compaction electrical resistivity of soil was measured for different dry density of soil. From the graph of volumetric dry density of soil versus water content of soil a slightly steeper increment in dry density can be observed for increasing water content. On the other hand in the case of dry density versus electrical resistivity graph, electrical resistivity almost remains same for increasing dry density until it reaches to the peak value. After achieving the maximum dry density a detrimental slopes can be observed in the both graphs. In the case of electrical resistivity of soil, after achieving maximum density of soil it does not decrease in remarkable extent. So except some dissimilarity a common trend can be observed in the both of the graphs. In both graphs after a maximum value, dry density tends to reduce. Also in both cases measured maximum dry density of soil was 1.79, 1.936, 1.792 and 1.821 gm/cm3 respectively.  So it can be concluded that for both cases electrical resistivity mostly depends on percentages of water in the soil rather than dry density. It is difficult measure dry density of soil from only electrical resistivity. But the maximum dry density of soil can be found from the least resistivity value.

Peaty soils are not suitable as foundation soils as they are weak and highly compressible. This paper describes a study on peat soil stabilisation to improve its physical and engineering properties. It investigates the effect of additives (binder amount 5%, 10% and 15% (85%cement, 15% bentonite) and range of sand 5% to 25% on the index properties as well as, pH, compaction, California Bearing Ratio and unconfined compressive strength of tropical peat soils. The amount of additives added to the peat soil sample was investigated in terms of the percentage of the dry soil mass. The results showed that of the additive admixtures altered the engineering properties of tropical peat soils. The soil liquid limit was found to decrease with increase of the additive content. The pH was found to increase with increase binder. The maximum dry density was found to increase while the optimum moisture content was found to decrease with the increase of the additive content. The California Bearing Ratio of the soil was found to increase significantly with increase in the additives. © 2008 ejge.

ejge.com/2008/Ppr0834/Ppr0834.pdf

Peaty soils are not suitable as foundation soils as they are weak and highly compressible. This paper describes a study on peat soil stabilisation to improve its physical and engineering properties. It investigates the effect of additives (binder amount 5%, 10% and 15% (85% ...

Infiltration is the process by which water on the ground surface enters the soil. For the calculation of runoff we have to determine Infiltration capacity. Runoff is contributed from large catchment area where ground conditions are different, bulk density may be different from place to place and therefore infiltration capacity also. For determination of runoff infiltration is an important parameter. Present study is an attempt to understand the various methods used for measurement of infiltration capacity and how the infiltration rate is measured on field by double ring infiltrometer. Also the relation of infiltration capacity with the soil parameters (Bulk Density, water content, Dry Density) This study has been done by a detailed research and analysis of some papers written by well-known researchers in the above field.

Swelling characteristics of compacted bentonite is the most important factor for nuclear waste disposal facilities. Salinity effect on swelling behaviour of compacted bentonite was investigated experimentally. A series of one dimensional swelling deformation tests have been performed. The tests were conducted for various initial dry densities from 1.33 g/cm 3 to 1.90 g/cm 3 for compacted bentonite saturated with NaCl of various concentrations in solution from 0 to 4.0 M. It was found that initial dry density and concentration of NaCl strongly influence the swelling rate of bentonite. The swelling rate of bentonite decreases with increasing the concentration of NaCl. Swelling rate depends on the concentration of NaCl more than on initial dry density and loading effect. Bentonite may change from highly swelled material to coagulate in saline water. Liquid limit of bentonite is also remarkably decreased with the change of liquid from distilled water to saline one, while the plastic limit is slightly increased.

http://www.dbc.wroc.pl/Content/13794/epe2_2011.pdf#page=65

Lateritic soils derived from migmatite-gneiss, granite, charnockite and quartzite from Basement Complex terrain in Southwestern Nigeria were investigated for their basic geotechnical properties. This is with a view to analyzing variations in liquid limits, dry densities and moisture contents of the soils between and within parent rock groups. The significance of mean group (parent rock) differences was tested at 5% level of significance (p = 0.05) using one-way multivariate analysis of variance (one-way MANOVA). Results obtained indicate significant main effects of parent rock on liquid limit (F (3, 8) = 56.11, p < 0.001, partial η 2 = 0.955), moisture content (F (3, 8)= 5.17, p = 0.028, partial η 2 = 0.660), and dry density (F (3, 8)= 6.88, p < 0.013, partial η 2 = 0.721). Calculated effect size for each variable reveals 96, 72 and 66 % of variance in liquid limit, dry density and moisture content respectively are accounted for by mean group (parent rock) differences. Scheffe post hoc test compared the dependent variables among the four parent rock groups in a multiple pair-wise manner. It indicates that liquid limit is the most sensitive to parent rock difference among the three variables investigated.

Safe and effective disposal of waste tyres have become a challenge today as the number of wastes tyres lying about increase daily and pose both environmental pollution and health problem to individuals. This study is aimed at evaluating the characteristics strength of soil reinforced with waste rubber tyre strips which will in turn cause a major reduction and subsequent elimination of the problem aforementioned. The soil samples used for this research were obtained from the University of Benin, from three different bore holes at depths of 1.0m and 1.5m each. Soil tests were carried out on the soil sample in its natural state which included natural moisture content specific gravity, sieve analysis, Atterberg limit, compaction and California Bearing Ratio (CBR) tests. The soil samples were thereafter reinforced with the waste tyre strips of sizes 0.5cm and 0.8 cm. Compaction test and CBR test were also carried out on the soil reinforced with waste rubber tyre strips. The results from the test showed that the soil did not increase in strength but rather reduced because the value of the Maximum Dry Density (MDD) decreased slightly with the reinforcing material from 1.67g/cm 3 to 1.82g/cm 3 for the unreinforced to 1.62g/cm 3 to 1.73g/cm 3 for the reinforced likewise the CBR results which reduced from (3.01% to 20.32%) to (1.73% to 7.68%) for the soaked and from (5.04% to 24.77%) to (6.77% to 21.55%).