Laboratory penetration tests

Laboratory Penetration Tests. Bench-scale laboratory penetration tests were performed to evaluate the possibility of applying molten sulfur directly to soil test specimens consisting of fine construction sand to stabilize them from wind and rain erosion. The emphasis was on penetration of the sulfur or chemically modified sulfur into the test specimen directly, thus avoiding the necessity of applying external heat to promote penetration. 

California bearing ratio tests are used to evaluate subgrades for pavements. These tests may be carried out in the field or in the laboratory. Such tests determine the resistance to penetration of a subgrade soil relative to that of a standard crushed-rock base. 

Crowse, J.L., Dejonge, J.O., and Calogero, F. (1990) Pesticide barrier performance of selected nonwoven fabrics in laboratory capillary and pressure penetration testing, Textile Research., 60 137-142. 

AGB stars constitute excellent laboratories to test the theory of stellar evolution and nucleosynthesis. Their particular internal structure allows two important processes to occur in them. First is the so-called 3(,ldredge-up (3DUP), a mixing mechanism in which the convective envelope penetrates the interior of the star after each thermal instability in the He-shell (thermal pulse, TP). The other is the activation of the s-process synthesis from alpha captures on 13C or/and 22Ne nuclei that generate the necessary neutrons which are subsequently captured by iron-peak nuclei. The repeated operation of TPs and the 3DUP episodes enriches the stellar envelope in newly synthesized elements and transforms the star into a carbon star, if the quantity of carbon added into the envelope is sufficient to increase the C/O ratio above unity. In that way, the atmosphere becomes enriched with the ashes of the above nucleosynthesis processes which can then be detected spectroscopically. 

Soil Column Tests. In the sand penetration test, a minimal amount of water was used. No consideration was given to the hydrostatic pressure which would occur in nature from a body of surface water. A new soil infiltration test was developed to take this into consideration. This test used a maximum amount of water (200 mL) on a minimum amount of treated soil (10 g) and was restricted only by the dimensions of the laboratory equipment. Our aim was to prepare an hydrophobe for soil which would support water over an extended period of time. Whereas water passed through soil treated with hydrophilic compounds within 8 hr, 2 weeks or more were required for penetration through an hydrophobe-treated soil. In the latter case the water level dropped 6 mm or less each day, showing that the cationic surfactant greatly hindered, but did not completely restrict the passage of water. The tests were usually terminated after 2 weeks, due to the large number of samples to be tested. 

Field Tests. A series of nine test plots were sprayed with modified sulfur mixtures which were based on the laboratory penetration and reaction test results. Rectangular test plots 6 X 7% ft (1/1000 acre) were built and filled with fine construction sand. Before spraying with the molten sulfur, half of each plot was textured by raking to produce a... 

The principle of the water intrusion test derives from the mercury intrusion test, which (applicable to both hydrophilic and hydrophobic membranes) is restricted to laboratory conditions. The membrane is placed in contact with the fluid (water in the case of the water penetration test, mercury in the case of the mercury intrusion test), and the pressure is increased, with the purpose of forcing the fluid into the pores. The volume of fluid forced into the pores is a measure of pore size and void space volume and thus of filter integrity. 

Stingray seafloor jacking unit. (After McNeilan, T.W., and Bugno, W.T., Cone penetration test results in offshore California silts. In Strength Testing of Marine Sediments Laboratory and In Situ Measurements, STP 883, Chaney, R.C., and Demars, K.R., eds., American Society for Testing and Materials, Philadelphia, PA, 55-71,1985. Reprinted with permission. Copyright ASTM.)... 

Equations 10.2 through 10.5 present the fundamental basis of any axial capacity determination, irrespective of the method to establish the soil parameters/and q. Several computation techniques are available to derive unit skin friction and unit end bearing either from laboratory and sampling data or from in-situ test data. The in-situ test most utilized is the cone penetration test (CPT). Details on the performance of the CPT can be found in Andresen et al. (1979) and de Ruiter (1971,1975). 

Vermeiden, J. 1977. Cone penetration test, December. LGM Mededelingen Report, Site Investigations, Delft Soil Mechanics Laboratory, Delft, the Netherlands, pp. 55-68. 

The surfaces of bulk storage piles frequently are exposed to humid atmospheres thus, it is of interest to know how rapidly moisture will be absorbed and how rapidly and to what depth wetting and phyacal deterioration will progress. The laboratory absorption-penetration test provides a method for evaluating these effects of pile exposure [1,3,8]. 

Results of the laboratory absorption-penetration tests are indicative of expected bulk fertilizer behavior under... 

Dowson, D. and Wallbridge N.C. (1985) Laboratory wear tests and clinical observations of the penetration of femoral heads into acetabular cups in total replacement hip joints I Charnley prosthesis with polytetrafluoroethylene acetabular cups. Wear, 104, 203-215. 

Unconfined compressive strength means the load per unit area at which a soil will fail in compression. It can be determined by laboratory testing, or estimated in the field using a pocket penetrometer, by thumb penetration tests, and other methods. 

If the potential fill material has a cohesive nature, in-situ vane shear tests may be performed to determine the undrained shear strength (see section 3.4.2.1 and Appendix B.2.3.2). Alternatively, Cone Penetration Tests could be undertaken to indirectly assess the undrained shear strength using existing correlations (see Appendix C). Undisturbed samples of the cohesive strata could be recovered from boreholes which are subsequently tested in the laboratory. For more details on slope stability analysis reference is made to section 8.4.3.7 of this Manual. 

State parameter y/, the preferred measure of in situ state within a critical state framework, can be measured (interpreted) from cone penetration tests with reasonable precision. Without measuring the critical state properties of the sand (e.g. M, A), shear modulus G or plastic hardening, interpretation relies on the friction ratio and parameters as indicators of material type and a precision in of 0.08 is possible. With supporting laboratory testing to determine the critical state parameters and measurement of with a seismic CPT, a precision in Xffof 0.02 can be achieved. Plewes et al. (1992), Been and Jefferies (1992) and... 

There are two general and standard methods for evaluating the CRR and one new method for finer grained soils (sandy silts to clayey silts). The two standard methods are based on processing penetration test data the new method requires laboratory testing of undisturbed samples. 

Technical specifications for hydraulic fill projects often specify criteria for the materials to be used within the reclamation. Verification of these criteria can be done by means of material testing. A physical sample taken from the fill area can be checked in a laboratory with respect to, for example, the specified maximum percentage of fines. Cone Penetration Tests executed on newly reclaimed land can further demonstrate whether a specified cone resistance is satisfied or not. 

Baldi et al. (1989) proposed a V -Gq relationship developed with Po River Sand and is meant for uncemented, silica sand. Rix and Stokoe (1992) updated the Baldi et al. (1989) relationship between Go and V, by including laboratory cone penetration tests in calibration chambers ... 

Brandenberg SJ, Bellana N, Shantz T (2010) Shear wave velocity as function of standard penetration test resistance and vertical effective stress at California bridge sites. Soil Dyn Earthq Eng 30 1026-1035 Brignoli EG, Gotti M, Stokoe KH (1996) Measurement of shear waves in laboratory specimens by means of piezo-electric transducers. Geotech Test J 19(4) 384-397... 

The radiation and temperature dependent mechanical properties of viscoelastic materials (modulus and loss) are of great interest throughout the plastics, polymer, and rubber from initial design to routine production. There are a number of laboratory research instruments are available to determine these properties. All these hardness tests conducted on polymeric materials involve the penetration of the sample under consideration by loaded spheres or other geometric shapes [1]. Most of these tests are to some extent arbitrary because the penetration of an indenter into viscoelastic material increases with time. For example, standard durometer test (the "Shore A") is widely used to measure the static "hardness" or resistance to indentation. However, it does not measure basic material properties, and its results depend on the specimen geometry (it is difficult to make available the identity of the initial position of the devices on cylinder or spherical surfaces while measuring) and test conditions, and some arbitrary time must be selected to compare different materials. 

There are many ways to measure these properties and some of them are proprietary. However, most laboratory tests are standardized by American Standard Testing Methods (ASTM). Many of them are interactive to various degrees. The rate and state of vulcanization is especially important to consider for components of heavier and thicker tines. The heat used to vulcanize the tine in a mold under pressure requites time to penetrate from both sides of the giant tine to the innermost portions. Securing a balanced state of cure, ie, the maximizing of physical properties in all the components, results in the innermost components having a faster rate of cure. The peripheral compounds should have a cure system which holds its physical properties well when overcured. 

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