In order to achieve the economical assessment of liquefaction safeness for an individual residential property by Swedish Ram Sounding (SRS), an attempting research on evaluating the grain-size properties of strata employing acoustic properties of soils was carried out. The sounds generated by friction between soils and stainless-steel metal during direct shear testing and SRS were recorded. And then, their acoustic properties were compared with grain size properties of soils. As results of examination on their relationships, the possibility was discovered that that the fines content, Fc, at certain stratum and presence or non-presence of plasticity of fines would be able to estimate based on the spectrum shape of frictional sound. The trends were also observed that the frictional sound of soils without plastic fines has narrow spectrum width and its peak frequency might be affected by particle size.

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Obtaining good samples from loose sand layers within bay areas are necessary to evaluate their deformation and liquefaction properties. Until now, high-quality sampling in the loose sandy ground are achieved by applying an expensive in-situ freezing technique. In order to find an alternative and cost-effective sampling method applicable to these loose alluvial deposits, sand samples were collected in this study from Kobe Bay area by using two different types of sampler and were comparatively examined by evaluating their physical properties, deformation characteristics and liquefaction strength. A close match of relative density, deformation properties and that of liquefaction strength properties to that of the field was shown by the samples collected by GS sampler than the Triple-tube types. This suggests a possibility of using a relatively less expensive GS sampler to collect high-quality samples from a loose sandy ground that is now primarily being applied for waste collection.

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The present study incorporates the scale down model of Jonardo dynamic penetrometer to determine the uniformity of the soil profile and also results in finding out the resistance offered by the soil mass. Four different sand samples of uniform gradation have been collected from various parts of India. The sand samples have been reconstituted using the conventional rainfall pouring technique through air pluviation. The samples have been prepared at different heights of fall and their uniformity has been quantified using the dynamic penetrometer. The soil resistance has been measured at various locations across the soil sample and the results are presented.

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This paper presents about the high level of excess pore water pressure. The high excess pore water pressure was monitored during pile driving work at saturated stiff to hard soil layer of Pleistocene. This high pressure zone under the pile toe is considered to destroy the soil texture and generate liquefaction soil. From this case study, liquefaction phenomenon is understood to be developed in any type of soil, if the level of excess pore water pressure is big enough to destroy the soil texture.

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The applicability of the 45-mm and 50-mm samplers is examined for highly organic, clayey and sandy samples obtained from Holocene and Pleistocene tertiary clays and Holocene sand deposits at 41 sites including some abroad. It is confirmed that the 45-mm sampler can take high-quality samples just as well as rotary double-tube (JGS 1222-2012) and rotary triple-tube (JGS 1223-2012) samplers for soils having an unconfined compressive strength of q_u=8~1415 kN/m² and SPT N-values of 3~54. Therefore, the 45-mm sampler can be applied as a sampler of JGS 1221, JGS 1222 and JGS 1223 to recover undisturbed soil samples suitable for laboratory tests.

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A key parameter necessary to properly evaluate dynamic response of soil is shear modulus. The shear modulus is usually estimated by using shear wave velocity (Vs) of soil measured through in situ geophysical tests. Since the shear modulus is the key parameter for geotechnical earthquake engineering problems both quantitatively and qualitatively, its measurement shall be done precisely. However, in many cases, shear wave velocity is estimated through field test like SPT N-value of soil whenever the precise measurement of Vs is not available. There are many empirical equations exist worldwide which correlate soil type and SPT N-value with expected shear wave velocity. However, all these equations are developed based on some field measurements limited to selected sites and geology. In the present paper, actual shear wave velocity measurements for five different project sites are compared with that estimated using 22 soil specific correlations including correlations recommended for Indian soil sites. The selected five project sites represent different parts of India i.e. Gujarat, Punjab, Andhra Pradesh, Uttar Pradesh, consist of different geologic origins. Present study review available correlations and highlights that shear wave velocity estimated through available correlations differ largely with actual measured data. Since, the measurement of SPT N-value depends upon many factors, the direct measurement of shear wave velocity using correlations may not converge for actual engineering applications for many sites. The actual measured data along with SPT N-value measurement data are presented in the paper.

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The following article represents various methods for soil resistance – R identification under single pile based on the Republic of Kazakhstan guidelines. Analytical values obtained from formulas and empirical values based on plate load and CPT tests for deep foundation design bearing capacity. To study and evaluate design soil resistance – R just beneath the footing, theoretical calculations executed, at the same time, set of plate load test probing carried out on the depth 7.0 – 11.0 m, and diameter of the cross section plate 30 cm. Furthermore, dynamic and static test took place for single pile bearing capacity identification. Consequently, code of practice values validated with obtained experimental values. The pile cross section is 30 x 30 cm and length is 8.0-10.0 m. The physical and mechanical soil properties on the depth of 8.0 – 12.0 m state that bearing layer underneath the pile toe is loam with following design characteristics: cohesion = 27 - 41 kPa, angle of friction = 23 - 26 degrees, density = 19.2 – 19.5 ton/m3. It has to take into account that soil is saturated and the site located in impounded area. Load – settlement figure states that factored bearing capacity is 403 – 784 kN. Dry resistance unit soil results of CPTs for loam is 241 and 582 kN, with bearing capacity equals to 658 kH. Dynamic tests results reveal bearing capacity of the pile 606 kN. Plate load test results perform settlement of 0.58 cm in the range of 0.1 – 0.5 MPa loading. The modulus of deformation is 12.0 MPa. Settlement – loading figure and plate load test curve is linear at 10.2 m depth. Comparative results of single pile bearing capacity perform difference between design values of soil resistance underneath the pile toe in terms of shaft surface in analytical and experimental approaches.

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