In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ...In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies.展开更多
Field tests in geotechnical engineering are fundamental for identification of the underground conditions.The standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase b...Field tests in geotechnical engineering are fundamental for identification of the underground conditions.The standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).展开更多
A highway in the floodplain of the Abandoned Yellow River in the north of Jiangsu Province is recently remediated to reduce liquefaction potential using the dynamic compaction(DC)method of densification of in-place so...A highway in the floodplain of the Abandoned Yellow River in the north of Jiangsu Province is recently remediated to reduce liquefaction potential using the dynamic compaction(DC)method of densification of in-place soils.Firstly,the liquefaction potential of the soil at the project site is analysed according to the code of seismic design.Then the in-situ single point impact tests are performed on the liquefiable soil.Settlement of crater,excess pore pressure,ground heave and lateral deformation under DC impact are measured and analyzed.Subsequently, the standard penetration test(SPT)and cone penetration test(CPT)are used for investigating the compaction effectiveness.At last,the improvement effect of DC is discussed according to the technical specification of dynamic consolidation to ground treatment.The investigation results indicate that the DC technique is an effective way for remediating liquefiable soil in highway engineering practice.展开更多
This paper introduces novel explicit models to predict the frictional resistance of open and closed-ended pipe piles subjected to seismic loading.This research employs genetic programming(GP)and multiobjective genetic...This paper introduces novel explicit models to predict the frictional resistance of open and closed-ended pipe piles subjected to seismic loading.This research employs genetic programming(GP)and multiobjective genetic algorithm-based evolutionary polynomial regression(EPR-MOGA)to develop closed-form expressions for estimating pile frictional resistance,utilizing widely used input parameters for enhanced practicality and applicability in engineering practice.The proposed models are developed using only three input variables:the corrected standard penetration test(SPT)blow count(N1)60,the pile slenderness ratio(L/D),and the peak ground acceleration(PGA).This deliberate reduction in input complexity significantly enhances the models’applicability across a wide range of geotechnical scenarios and industries.The accuracy of the developed models was assessed via the coefficient of determination(R2),root mean squared error(RMSE),and mean absolute error(MAE).In the case of the GP model,the evaluation metrics for the testing set for open-ended piles(R2,RMSE,and MAE values)are 0.89,0.43,and 0.35,respectively,whereas the corresponding values for closed-ended piles are 0.93,0.38,and 0.3,respectively.On the other hand,the EPR-MOGA approach achieves similarly encouraging results,with performance metrics of 0.92,0.37,and 0.29 for open-ended piles and 0.91,0.39,and 0.30 for closed-ended piles.展开更多
The present paper examines the evaluation of liquefaction potential of an earth dam foundation in Tunisia. The assessment of soil liquefaction was made using deterministic and probabilistic simplified procedures devel...The present paper examines the evaluation of liquefaction potential of an earth dam foundation in Tunisia. The assessment of soil liquefaction was made using deterministic and probabilistic simplified procedures developed from several case histories. The data collected from the field investigation performed before and after the vibrocompaction are analyzed and the results are reported. The obtained results show that after vibrocompaction, a significant improvement of the soil resistance reduces the liquefaction potential of the sandy foundation. Indeed, in the untreated layers, the factor of safety FS drops below 1 which means that the soil is susceptible for liquefaction. However, in the compacted horizons, the values of FS exceed the unit which justifies the absence of liquefaction hazard of the foundation.展开更多
文摘In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies.
基金the sponsorship from the Brazilian government agencies CNPqFAPES
文摘Field tests in geotechnical engineering are fundamental for identification of the underground conditions.The standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).
基金Supported by the National Youth Science Foundation of China(40802065)the Jiangsu Province Ed-ucation Science Foundation(08KJD580004)the Innovation Research Foundation of Nanjing Institute of Technology(CKJ2011010)
文摘A highway in the floodplain of the Abandoned Yellow River in the north of Jiangsu Province is recently remediated to reduce liquefaction potential using the dynamic compaction(DC)method of densification of in-place soils.Firstly,the liquefaction potential of the soil at the project site is analysed according to the code of seismic design.Then the in-situ single point impact tests are performed on the liquefiable soil.Settlement of crater,excess pore pressure,ground heave and lateral deformation under DC impact are measured and analyzed.Subsequently, the standard penetration test(SPT)and cone penetration test(CPT)are used for investigating the compaction effectiveness.At last,the improvement effect of DC is discussed according to the technical specification of dynamic consolidation to ground treatment.The investigation results indicate that the DC technique is an effective way for remediating liquefiable soil in highway engineering practice.
文摘This paper introduces novel explicit models to predict the frictional resistance of open and closed-ended pipe piles subjected to seismic loading.This research employs genetic programming(GP)and multiobjective genetic algorithm-based evolutionary polynomial regression(EPR-MOGA)to develop closed-form expressions for estimating pile frictional resistance,utilizing widely used input parameters for enhanced practicality and applicability in engineering practice.The proposed models are developed using only three input variables:the corrected standard penetration test(SPT)blow count(N1)60,the pile slenderness ratio(L/D),and the peak ground acceleration(PGA).This deliberate reduction in input complexity significantly enhances the models’applicability across a wide range of geotechnical scenarios and industries.The accuracy of the developed models was assessed via the coefficient of determination(R2),root mean squared error(RMSE),and mean absolute error(MAE).In the case of the GP model,the evaluation metrics for the testing set for open-ended piles(R2,RMSE,and MAE values)are 0.89,0.43,and 0.35,respectively,whereas the corresponding values for closed-ended piles are 0.93,0.38,and 0.3,respectively.On the other hand,the EPR-MOGA approach achieves similarly encouraging results,with performance metrics of 0.92,0.37,and 0.29 for open-ended piles and 0.91,0.39,and 0.30 for closed-ended piles.
文摘The present paper examines the evaluation of liquefaction potential of an earth dam foundation in Tunisia. The assessment of soil liquefaction was made using deterministic and probabilistic simplified procedures developed from several case histories. The data collected from the field investigation performed before and after the vibrocompaction are analyzed and the results are reported. The obtained results show that after vibrocompaction, a significant improvement of the soil resistance reduces the liquefaction potential of the sandy foundation. Indeed, in the untreated layers, the factor of safety FS drops below 1 which means that the soil is susceptible for liquefaction. However, in the compacted horizons, the values of FS exceed the unit which justifies the absence of liquefaction hazard of the foundation.
