Earthquake Microzoning from Soil Properties

1993 ◽  
Vol 9 (2) ◽  
pp. 209-231 ◽  
Author(s):  
A. P. W. Hodder ◽  
M. Z. Graham
Keyword(s):  
Shear Strength ◽  
New Zealand ◽  
Linear Regression ◽  
Soil Properties ◽  
Shear Wave Velocity ◽  
Soil Type ◽  
Soil Profile ◽  
Soil Structure ◽  
Viscous Damping ◽  
Extent Of Damage

The extent of damage caused by an earthquake in Wellington, New Zealand, in 1968 to buildings erected on a variety of regoliths and foundation materials is correlated with the thickness of the regolith, the depth to the water table and semi-quantitative parameters derived from soil profile descriptions, particularly related to soil type and soil structure. From linear regression correlations, the expected damage for a comparable earthquake elsewhere can be determined. The model was tested for soil data for the Edgecumbe area, hit by a damaging earthquake in 1987. The predictions were sufficiently in accord with observations to suggest that soil properties that reflect the geotechnical properties of the upper parts of the regolith, particularly those that measure the shear strength, shear wave velocity and viscous damping of that material, may be useful for earthquake microzoning purposes in areas where there is a considerable thickness of unconsolidated materials above bedrock.

scholarly journals Diagnostic problems of elementary soil processes and profile-differentiated soils of the Precarpathian region

2016 ◽  
Vol 17 (1-2) ◽  
pp. 40-48
Author(s):  
I. S. Smaga
Keyword(s):  
Chemical Composition ◽  
Soil Properties ◽  
Diagnostic Criteria ◽  
Humic Acids ◽  
Soil Type ◽  
Soil Profile ◽  
Laboratory Simulation ◽  
Soil Processes ◽  
Acid Base ◽  
Genetic Nature

Present condition, scientific concepts and ways of further development of diagnosis problem of elementary soil processes and genetic nature profiled-differentiated gleyed soils of the Pre-Carpathian region, known as brownish-podzolic, brownsoil-podzolic and sod-podzolic, based on stable indicators of soil properties are studied. Eluvial-illuvial differentiation nature of the soil profile of the studied soils is founded. The aim of research was to develop criteria for the diagnosis of elementary soil processes and genetic nature profiled-differentiated soil deposits of Ciscarpathia and discovering of the parameters of the relevant indicators of soil properties. The soil profile with his characteristic set of genetic horizons and morphological characteristics can result from taking place of both various set (kit) of ESP and of varying intensity of individual processes (complex ESP). Formation of genetic soil type is caused by the course of the profile forming (main) process with the possible participation of several (related) processes. An important condition for the diagnostic determination of profile-differentiated soils in the Ciscarpathia is the search for reliable diagnostic criteria for basic elementary soil processes (ESP) which play a crucial role in the genesis and determine their macromorphological characteristics: lessivage, podzolisation, gleying and eluvial-gleying processes. Diagnostic criteria of the elluvial processes resulted in gross chemical composition of the soil (molecular ratio), particle size distribution (loss sludge) and mineralogy silt fraction (montmorillonite content) were tested. The criteria for establishing genetic origin of the Pre-Carpathian soils, podzolization and eluvial-gley processes detection and their possible parameters were suggested. Followed the impact of the prevailing development of individual creating profile elementary soil processes (podzolization, eluvial-gley and gleying) by laboratory simulation modeling of soil regimes that are conducive to them (washing, water stagnant and contrast) for evaluative indicators of acid-base soil buffer and made the conclusions about the possibility of these processes isolation. Eluvial-illuvial differentiation of Ciscarpathia typical soils is coursed by passage of profile forming process of podzolisation (acid hydrolysis, podzolic) and related from the group of eluvial - eluvial-gleying process and lessivage. They are diagnosed by the gross grain and chemical composition of the soil and the content of montmorillonite. Brown soil forming processes have a significant impact on the formation of humus status and physical and chemical properties of the studied soil. Substantiated differences forming the group composition of humus and fractional composition of humic acids of soils formed underbrownsoil formation processes from the sod soils type (the ratio of humic acids to fulvic acid, gumatcalcium content, optical density of humic substances). Advantages and disadvantages of using quantitative identification criteria - profile humus accumulation factor in the genetic diagnosis of soil type are analyzed. In the conditions of wash and contrasting modes of moisture, causing the priority development processes of podzolisation and  gleye- eluvial respectively a similar trend of formation of acid-base buffer capacity of soil and similar parameters of evaluating indicators within the soil profile are observed. It is impossible to separate the processes of podzolisation and  gleye- eluvial using the indicators of acid-base buffering. Describing of profile structure, morphological and genetic traits of genetic horizons, the profile distribution of acid-base buffering indicators (even without the use of criteria based on gross chemical and grain composition and content of clay minerals) help to clear identify brownish-podzolic gley soils of Ciscarpathia.

scholarly journals Effect of Earthing Enhancing Compound (EEC) on Improving Tower Footing Resistance of a 500 kV Tower in a Rocky Area

2021 ◽  
Vol 11 (12) ◽  
pp. 5623
Author(s):  
Nur Alia Farina Mohd Nasir ◽  
Mohd Zainal Abidin Ab Kadir ◽  
Miszaina Osman ◽  
Muhamad Safwan Abd Rahman ◽  
Ungku Anisa Ungku Amirulddin ◽  
...  
Keyword(s):  
Electromagnetic Field ◽  
Comparative Analysis ◽  
Transmission Line ◽  
Structure Analysis ◽  
Current Distribution ◽  
Soil Profile ◽  
Soil Structure ◽  
Soil Resistivity ◽  
Transmission Towers ◽  
Rocky Soil

This paper presents a comparative analysis of different earthing designs’ performances, with particular interest on the use of earthing enhancing compound (EEC) for a selected earthing design of 500 kV transmission towers in a rocky soil, using the SESCAD tool of the Current distribution, electromagnetic field grounding and soil structure analysis (CDEGS) software. The simulation included the interpretation of soil profile and comparison between designs A, B and C, which are currently used for the 500 kV tower footing resistance (TFR) improvement. Results showed each design had reduced the TFR by 66%, 54.7% and 63.2% for the towers T42, T48 and T50, respectively. In some cases, further improvement of TFR is required, especially in the rocky area where the soil resistivity (SR) value is of more than 500 Ω⋅m. In this case, EEC was used in Design C, encasing both the vertical and horizontal electrodes, and it reduced the TFR further by 16% to 20%. The characteristics of the soil and earthing arrangement design play an important role in achieving a low TFR value, which is directly proportional to the backflashover occurrence and thus to the transmission line performance.

Shear Strength Monitoring System Based on Measurement of Shear Wave Velocity and Moisture Content

2014 ◽  
Vol 635-637 ◽  
pp. 750-754
Author(s):  
Peng Hu ◽  
Qing Li ◽  
Yi Wei Xu ◽  
Nan Ying Shentu ◽  
Quan Yuan Peng
Keyword(s):  
Shear Strength ◽  
Moisture Content ◽  
Shear Wave ◽  
Monitoring System ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Bender Elements ◽  
Strength Measurement ◽  
Soil Shear Strength ◽  
The Relationship

Expound the importance of soil shear strength measurement at mudslide hidden point to release the loss caused by the disaster, explain the relationship between shear wave velocity, moisture content and shear strength, design the shear strength monitoring system combining the shear wave velocity measured by Piezoelectric bender elements and moisture content.

Correlation of pH on Soil Physicochemical Properties using Linear Regression Model for Spectral Data Analysis

2021 ◽  
Vol 10 (1) ◽  
pp. 3492-3500
Author(s):  
Vipin Y. Borole ◽  
◽  
Sonali B. Kulkarni ◽  
Keyword(s):  
Linear Regression ◽  
Plant Growth ◽  
Physicochemical Properties ◽  
Regression Model ◽  
Soil Properties ◽  
Spectral Data ◽  
Linear Regression Model ◽  
Soil Analysis ◽  
Soil Physicochemical Properties ◽  
Analytical Technique

Soil properties may be varied by spatially and temporally with different agricultural practices. An accurate and reliable soil properties assessment is challenging issue in soil analysis. The soil properties assessment is very important for understanding the soil properties, nutrient management, influence of fertilizers and relation between soil properties which are affecting the plant growth. Conventional laboratory methods used to analyses soil properties are generally impractical because they are time-consuming, expensive and sometimes imprecise. On other hand, Visible and infrared spectroscopy can effectively characterize soil. Spectroscopic measurements are rapid, precise and inexpensive. Soil spectroscopy has shown to be a fast, cost-effective, environmentally friendly, non-destructive, reproducible and repeatable analytical technique. In the present research, we use spectroscopy techniques for soil properties analysis. The spectra of agglomerated farming soils were acquired by the ASD Field spec 4 spectroradiometer. Different fertilizers treatment applied soil samples are collected in pre monsoon and post monsoon season for 2 year (4 season) for banana and cotton crops in the form of DS-I and DS-II respectively. The soil spectra of VNIR region were preprocessed to get pure spectra. Then process the acquired spectral data by statistical methods for quantitative analysis of soil properties. The detected soil properties were carbon, Nitrogen, soil organic matter, pH, phosphorus, potassium, moisture sand, silt and clay. Soil pH is most important chemical properties that describe the relative acidity or alkalinity of the soil. It directly effect on plant growth and other soil properties. The relationship between pH properties on soil physical and chemical parameters and their influence were analyses by using linear regression model and show the performance of regression model with R2 and RMSE. Keywords soil; physicochemical properties; spectroscopy; pH

Sensitivity analysis of geotechnical site conditions effect on the seismic response of a saturated inhomogeneous poroviscoelastic soil profile

2018 ◽  
Vol 15 (6) ◽  
pp. 661-677 ◽  
Author(s):  
Toufiq Ouzandja ◽  
Mohamed Hadid
Keyword(s):  
Soil Properties ◽  
Seismic Response ◽  
Pore Water ◽  
Soil Profile ◽  
Water Saturation ◽  
Free Field ◽  
Response Spectra ◽  
Response Analysis ◽  
Content Type ◽  
Linear And Nonlinear

Purpose This paper aims to present the investigation of the linear and nonlinear seismic site response of a saturated inhomogeneous poroviscoelastic soil profile for different soil properties, such as pore-water saturation, non-cohesive fines content FC, permeability k, porosity n and coefficient of uniformity Cu. Design/methodology/approach The inhomogeneous soil profile is idealized as a multi-layered saturated poroviscoelastic medium and is characterized by the Biot’s theory, with a shear modulus varying continuously with depth according to the Wichtmann’s model. Seismic response analysis has been evaluated through a computational model, which is based on the exact stiffness matrix method formulated in the frequency domain assuming that the incoming seismic waves consist of inclined P-SV waves. Findings Unlike the horizontal seismic response, the results indicate that the vertical one is strongly affected by the pore water saturation. Moreover, in the case of fully saturated soil profile, the same vertical response spectra are found for the two cases of soil behavior, linear and nonlinear. Originality/value This research is a detailed study of the geotechnical soil properties effect on the bi-directional seismic response of saturated inhomogeneous poroviscoelastic soil profile, which has not been treated before; the results are presented in terms of the peak acceleration ratio, as well as the free-field response spectra and the spectral ratio (V/H).

scholarly journals Relationship between Shear Wave Velocity and SPT-N Value for Residual Soils

2018 ◽  
Vol 203 ◽  
pp. 04009
Author(s):  
Nor Faizah Bawadi ◽  
Nur Jihan Syamimi Jafri ◽  
Ahmad Faizal Mansor ◽  
Mohd Asri Ab Rahim
Keyword(s):  
Surface Wave ◽  
Shear Wave ◽  
Wave Velocity ◽  
Shear Wave Velocity ◽  
Soil Profile ◽  
Dynamic Parameter ◽  
Kuala Lumpur ◽  
Residual Soils ◽  
Standard Penetration Testing ◽  
Wave Methods

The shear wave velocity (Vs) is an important dynamic parameter in the field of geotechnical engineering. One of the surface wave methods is Spectral Analysis of Surface Wave (SASW) has received attention in obtaining the shear wave velocity (Vs) profile by analysing the dispersion curve. SASW is a non-destructive test, fast and time-effective for field survey. Thus, this paper proposed the application of SASW method to obtain the shear wave velocity (Vs) to represent the soil profile. This paper aims to determine the shear wave velocity (Vs) profile using SASW method, where the testing has been conducted at three site of residual soils located in Damansara, Kuala Lumpur and Nilai area. In this study, it shows that the soil profile obtained from shear wave velocity value is similar pattern with profile that obtained using Standard Penetration Testing (SPT), which conventional used in field. The shear wave velocity are proportionally increase with depth.

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