The Effects of Vertical Stress on the Liquefaction Potential Originated from Buildings in The Urban Areas

2020 ◽  
pp. 351-372
Author(s):  
Mehmet Ozcelik
Keyword(s):  
Urban Areas ◽  
Sandy Soils ◽  
Standard Penetration Test ◽  
Soil Liquefaction ◽  
Vertical Stress ◽  
Limited Information ◽  
Liquefaction Potential ◽  
Empirical Procedure ◽  
Seismic Forces

Main purpose of this paper is to study the influence of vertical stress on soil liquefaction in urban areas. The literature provides limited information on vertical stress analysis of multiple footings, and, as a result, there is no accurate way to account for the effect of the foundation depth on liquefaction. Additionally, practical methods do not exist for considering the interaction between the neighboring foundations vertical stress and seismic forces in the urban area. Vertical stress distribution was calculated in examining the soil liquefaction potential exhibited by building foundations as a case study. The vertical stresses were chosen randomly for some buildings with foundation depths of 3.00 m; 4.50 and 6.00 m at the Burkent site (Burdur-Turkey). The influence of 5-storey buildings on the liquefaction potential of sandy soils was evaluated in terms of the safety factor (FS) against liquefaction along soil profile depths for different earthquakes. Standard Penetration Test (SPT) results were used based on simplified empirical procedure.

The Effects of Vertical Stress on the Liquefaction Potential Originated from Buildings in The Urban Areas

2017 ◽  
Vol 8 (1) ◽  
pp. 38-57
Author(s):  
Mehmet Ozcelik
Keyword(s):  
Urban Areas ◽  
Standard Penetration Test ◽  
Soil Liquefaction ◽  
Vertical Stress ◽  
Limited Information ◽  
Penetration Test ◽  
Liquefaction Potential ◽  
Empirical Procedure ◽  
Seismic Forces

Main purpose of this paper is to study the influence of vertical stress on soil liquefaction in urban areas. The literature provides limited information on vertical stress analysis of multiple footings, and, as a result, there is no accurate way to account for the effect of the foundation depth on liquefaction. Additionally, practical methods do not exist for considering the interaction between the neighboring foundations vertical stress and seismic forces in the urban area. Vertical stress distribution was calculated in examining the soil liquefaction potential exhibited by building foundations as a case study. The vertical stresses were chosen randomly for some buildings with foundation depths of 3.00 m; 4.50 and 6.00 m at the Burkent site (Burdur-Turkey). The influence of 5-storey buildings on the liquefaction potential of sandy soils was evaluated in terms of the safety factor (FS) against liquefaction along soil profile depths for different earthquakes. Standard Penetration Test (SPT) results were used based on simplified empirical procedure.

scholarly journals Assessment of liquefaction potential index for Mumbai city

2012 ◽  
Vol 12 (9) ◽  
pp. 2759-2768 ◽  
Author(s):  
J. Dixit ◽  
D. M. Dewaikar ◽  
R. S. Jangid
Keyword(s):  
Standard Penetration Test ◽  
Soil Liquefaction ◽  
Reclaimed Land ◽  
Liquefaction Potential ◽  
Contour Maps ◽  
Empirical Procedure ◽  
Liquefaction Potential Index ◽  
Potential Index ◽  
The City ◽  
Mumbai City

Abstract. Mumbai city is the financial capital of India and is fifth most densely populated city in the world. Seismic soil liquefaction is evaluated for Mumbai city in terms of the factors of safety against liquefaction (FS) along the depths of soil profiles for different earthquakes with 2% probability of exceedance in 50 yr using standard penetration test (SPT)-based simplified empirical procedure. This liquefaction potential is evaluated at 142 representative sites in the city using the borehole records from standard penetration tests. Liquefaction potential index (LPI) is evaluated at each borehole location from the obtained factors of safety (FS) to predict the potential of liquefaction to cause damage at the surface level at the site of interest. Spatial distribution of soil liquefaction potential is presented in the form of contour maps of LPI values. As the majority of the sites in the city are of reclaimed land, the vulnerability of liquefaction is observed to be very high at many places.

scholarly journals Assessment of soil liquefaction potential: a case study for Moulvibazar town, Sylhet, Bangladesh

2020 ◽  
Vol 2 (4) ◽  
Author(s):  
Md. Shakhawat Hossain ◽  
A. S. M. Maksud Kamal ◽  
Md. Zillur Rahman ◽  
Atikul Haque Farazi ◽  
Dhiman Ranjan Mondal ◽  
...  
Keyword(s):  
Soil Liquefaction ◽  
Liquefaction Potential

Evaluating cyclic liquefaction potential using the cone penetration test

1998 ◽  
Vol 35 (3) ◽  
pp. 442-459 ◽  
Author(s):  
P K Robertson ◽  
CE (Fear) Wride
Keyword(s):  
Earthquake Engineering ◽  
Sandy Soils ◽  
Cone Penetration Test ◽  
Soil Liquefaction ◽  
Penetration Test ◽  
Cone Penetration ◽  
Liquefaction Resistance ◽  
Liquefaction Potential ◽  
Engineering Research ◽  
Research Workshop

Soil liquefaction is a major concern for structures constructed with or on sandy soils. This paper describes the phenomena of soil liquefaction, reviews suitable definitions, and provides an update on methods to evaluate cyclic liquefaction using the cone penetration test (CPT). A method is described to estimate grain characteristics directly from the CPT and to incorporate this into one of the methods for evaluating resistance to cyclic loading. A worked example is also provided, illustrating how the continuous nature of the CPT can provide a good evaluation of cyclic liquefaction potential, on an overall profile basis. This paper forms part of the final submission by the authors to the proceedings of the 1996 National Center for Earthquake Engineering Research workshop on evaluation of liquefaction resistance of soils.Key words: cyclic liquefaction, sandy soils, cone penetration test

Regression model for evaluating liquefaction potential by discriminant analysis of the SPT N value

2005 ◽  
Vol 42 (3) ◽  
pp. 856-875 ◽  
Author(s):  
Sheng-Yao Lai ◽  
Ping-Sien Lin ◽  
Ming-Jyh Hsieh ◽  
Hoi-Fung Jim
Keyword(s):  
Discriminant Analysis ◽  
Standard Penetration Test ◽  
Cyclic Stress ◽  
Soil Liquefaction ◽  
Liquefaction Resistance ◽  
Multivariate Statistical ◽  
Liquefaction Potential ◽  
Cyclic Stress Ratio ◽  
N Value ◽  
Spt N Value

Discriminant models are developed for evaluating soil liquefaction potential, using standard penetration test (SPT) data for 592 occurrences of liquefaction and nonliquefaction. The discriminant model used is a multivariate statistical method. The square root of the SPT N value, (N1)601/2, and the logarithm of the cyclic stress ratio, ln CSR7.5, are adopted as the major parameters for analyses. Two models measuring liquefaction resistance through the SPT N value are also established in this study, which allows calculated results to be compared with the empirical curves. Key words: liquefaction, discriminant analysis, misclassified probability.

scholarly journals Influence of Soil Liquefaction on the Structural Performance of Bridges During Earthquakes: Showa Bridge as A Case Study

2018 ◽  
Vol 7 (4.20) ◽  
pp. 146
Author(s):  
Mohammed K. Dhahir ◽  
Wissam Nadir ◽  
Mohammed H. Rasool
Keyword(s):  
Lateral Displacement ◽  
Bending Moment ◽  
Sandy Soils ◽  
Soil Liquefaction ◽  
Shallow Foundations ◽  
Structural Performance ◽  
Excess Pore Pressure ◽  
Regular Structures ◽  
Loss Of Contact

Liquefaction is generally defined as the loss of contact between soil particles during shaking (earthquakes), and it usually occurs in saturated loose sandy soils where the timescale is insufficient for the water to drain from the pores, thus increasing the excess pore pressure, and thereby floating the sand particles. For regular structures with shallow foundations, liquefaction normally leads to loss of soil strength, which leads to settlement of foundations. On the other hand, bridges are usually supported with piles foundation, which introduces additional effects during liquefaction. Therefore, this paper examines the possible effects of liquefaction on the structural performance of bridges during earthquakes. Furthermore, the failure of Showa Bridge during the 1964 Nagata earthquake was also discussed and analyzed as an example of the catastrophic effects of liquefaction. The analysis shows that the most influential effect during liquefaction is the increase in the unsupported length of piles, which leads to several adverse effects such as increasing the lateral displacement, reduce the buckling capacity, increase the bending moment, and reduce the shaft capacity of the pile. Finally, recommendations regarding the design of pile supported bridges in seismic areas with liquefiable soils have also been suggested. 

scholarly journals LPI Based Earthquake Induced Soil Liquefaction Susceptibility Assessment at Probashi Palli Abasan Project Area, Tongi, Gazipur, Bangladesh

2018 ◽  
Vol 10 (2) ◽  
pp. 105-116
Author(s):  
A. H. Farazi ◽  
N. Ferdous ◽  
A. S. M. M. Kamal
Keyword(s):  
Threshold Value ◽  
Flood Plain ◽  
Standard Penetration Test ◽  
Soil Liquefaction ◽  
Cumulative Frequency ◽  
Liquefaction Potential ◽  
Project Area ◽  
Potential Index ◽  
Liquefaction Hazard ◽  
Simplified Procedure

This study aims at evaluation of seismic soil liquefaction hazard potential at Probashi Palli Abasan Project area of Tongi, Gazipur, exploiting standard penetration test (SPT) data of 15 boreholes, following Simplified Procedure. Liquefaction potential index (LPI) of each borehole was determined and then cumulative frequency distribution of clustered LPI values of each surface geology unit was determined assuming cumulative frequency at LPI = 5 as the threshold value for liquefaction initiation. By means of geotechnical investigation two surface geological units—Holocene flood plain deposits, and Pleistocene terrace deposits were identified in the study area. We predicted that 14% and 24% area of zones topped by Pleistocene terrace deposits and zones topped by Holocene flood plain deposits, respectively, would exhibit surface manifestation of liquefaction as a result of 7 magnitude earthquake. The engendered hazard map also depicts site specific liquefaction intensity through LPI values of respective boreholes, and color index, which was delineated by mapping with ArcGIS software. Very low to low, and low to high liquefaction potential, respectively, was found in the areas covered by Pleistocene terrace deposits and Holocene flood plain deposits. LPI values of both units are such that sand boils could be generated where LPI > 5.

Reconsideration of case histories for estimating undrained shear strength in sandy soils

1999 ◽  
Vol 36 (5) ◽  
pp. 907-933 ◽  
Author(s):  
C E (Fear) Wride ◽  
E C McRoberts ◽  
P K Robertson
Keyword(s):  
Shear Strength ◽  
Sandy Soils ◽  
Standard Penetration Test ◽  
Undrained Shear Strength ◽  
Soil Liquefaction ◽  
Penetration Test ◽  
Case Histories ◽  
Original Case ◽  
Undrained Strength ◽  
Undrained Shear

When sandy soils respond in a strain-softening manner to undrained loading, an estimation of the resulting undrained shear strength (Su) is required to determine the potential for flow liquefaction at a given site. One of the most commonly used methods for estimating the undrained strength of liquefied sand is an empirical standard penetration test (SPT) based chart (originally proposed by H.B. Seed), which was developed using a number of case histories. The original interpretations of these case histories are viewed by many workers and regulatory agencies as the most authoritative measure of the liquefied strength of sand. Consequently, in comparison, other less conservative methods are generally held in an unfavourable light. This paper reexamines the original database of case histories in view of some more recent concepts regarding soil liquefaction. The objectives of this paper are to explore and reassess the issues involved in the original assessment and to offer alternative views of the case records. The conclusions presented here indicate that alternative explanations of the liquefied strength of sand are not inconsistent with the original case histories. Key words: sandy soils, soil liquefaction, undrained strength, standard penetration test (SPT).

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