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In many parts of the world, the Standard Penetration Test (SPT) is still the most commonly performed and often the only test performed during a site investigation. However, the SPT has received much criticismoverthepast50yearsasbeingatestthatisoftenconsideredastooinaccuratetobeofmuchvalue.Some engineers may feel that this is largely because the SPT...
Contexts in source publication
Context 1
... course, most engineers sim- ply add the resistance from the second and third increments to arrive at the requisite result from the test, i.e., the N-value. We may consider the sequence of driving a split spoon over the three 0.15 m incre- ments as shown in Figure 1. In order for the spoon to advance into the soil, assuming no plugging and full soil injection into the spoon during driving, the spoon must overcome "Equivalent Static" side and end forces as noted by Schmertmann (1979). ...
Context 2
... may make an initial estimate of the driving resistance or blowcounts attributed to the end bear- ing contribution to the SPT by considering the source of driving resistance shown in Figure 1 and suggested by Equations 4 and 5. We may note that: Table 2 gives values of E obtained for the data of Table 1 using Eqs. ...
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Citations
... These tests are laborious and time consuming and sometimes the results are not accurate due to the poor laboratory conditions (Venkatasubramanian and Dhinakaran, 2011). Lutenegger (2008) showed that the SPT provides three functions that can be used to evaluate soil properties through an analysis to illustrate how the incremental blow counts may be used to obtain more information from the test. Hooshmand et al. (2011) used SPT to investigate the strength and deformation characteristics of Tabriz marls and their stress-strain behaviour were investigated by various in situ and laboratory tests. ...
Strength characteristics of foundation soils in the six geo-political zones of Nigeria were evaluated based on standard penetration test (SPT) results using some conventional empirical/analytical models and the bearing capacity was predicted by numerical analysis using Plaxis 3D, a finite element application package. The SPT N-values were first corrected to the standard average energy of 60% (N60) before they were used to correlate soil properties. Evaluation of the soil properties were done at foundation embedment depths of 0.6, 2.1, 3.6, 5.1, 6.6, 8.1, 9.6, 11.1 and 12.6 m. The results of overconsolidation ratio, rigidity index, relative density, angle of internal resistance, undrained shear strength and unconfined compressive strength show that the strength characteristics of Nigerian soils is lowest on the average in the South South (SS) geo-political zone, followed by South West (SW), South East (SE), North East (NE), North West (NW) and the North Central (NC) geo-political zone has the highest prediction of strength characteristics. Bearing capacity generally increased with boring depth and having its lowest values in the SS geo-political zone and increased for the remaining zones in the order of SW, SE, NE, NW and the NC geopolitical zone.
... This tool has evolved throughout the years and has gained more attention in scientific research for subsurface exploration of equivocal zones. SPT is used for calculating static and dynamic properties of coarse-grained soils such as the internal friction angle (ϕ′), relative density (Dr), and bearing capacity and settlement, shear wave velocity (vs) of soils, liquefaction potential (Nassaji and Kalantari 2011;Lutenegger 2008;Fletcher 1965). Even though the SPT was originally developed for coarse-grained soils, it has been applied to fine-grained soils to estimate engineering properties such as undrained compressive strength, undrained shear strength, and coefficient of volume compressibility. ...
This work was undertaken within the framework of an environmental follow-up program of the Taparura zone after completion of depollution and artificial beach nourishment works along a coastline of 6 km in the northern coast of Sfax town, Tunisia. The realized recognition investigation aimed to explore the geomechanical characteristics of the surface sediment in the coastal fringe of the project site by evaluating its bearing capacity up to 500 m in the seaside from the new coastline in order to check the safety of the users. A Standard Penetration Test (SPT) with a penetration of approximately 45 cm concerned a total of 288 coastal stations along the zone. The results provided a detailed description of the geotechnical aspects of the sediment including the bearing capacity of the beach corresponding to the relaxed position on two feet, and the user load in motion on one foot, or half a foot. Finally, prognostic maps were respectively drawn that can serve as a guide for the safety of the beach users in a contribution to a local beach occupation plan.
... The reliabilitybased approach provides rational design criteria, accounting for all key sources of uncertainty in the foundation engineering process and thus should be the basis of design. Lutenegger (2008) showed that the SPT provides three numbers that can be used to evaluate soil properties through an analysis to illustrate how the incremental blow counts may be used to obtain more information from the test. Hooshmand et al. (2011) used SPT to investigate the strength and deformation characteristics of Tabriz marls and their stress-strain behavior were investigated by various in-situ and laboratory tests. ...
In many parts of the world, The Standard Penetration Test (SPT) is still considered one of the most common in-situ tests to evaluate the strength of coarse grained soil and often the only in-situ test performed during a site investigation. In the present study, site characteristics of Hilla city are investigated by using in-situ (SPT) test by drilling five boreholes distributed over Hilla city with different depths (15-17) m below natural ground surface. In this study, site characterization is treated as a task of function approximation of the large existing data from standard penetration tests of Hilla City, Iraq. The number of blows (N) from more than (950) field standard penetration tests has been collected with different depths from 110 boreholes spreaded over Hilla city, Iraq. Distribution and variation of N values of standard penetration tests at different depths are presented and discussed in this paper. Results from data analysis show that large variation of N values occurs at the upper layer of the soil and that variations decrease with increasing depth below ground surface. The results indicate that N values increase with increasing the depth to approximately 5 meters below natural ground surface, after that N values decrease with increasing the depth up to 8 m, then N values increase with increasing depth below 8m. Mathematical model is presented by using Statistica program to find N values (number of blows) of SPT test for Hilla city by using GPS coordination (Latitude (N) and longitude (E)) in any location of the study area. The results obtained show that the statistical model is accurate in predicting N values (number of blows) of SPT test in Hilla city and that the empirical equation can be depended on.
Despite its many perceived shortcomings, the Standard Penetration Test remains the most common site investigation tool used throughout the world. The results from the SPT are often used to estimate side resistance of piles. The SPTTorque Test or SPT-T is a simple modification to the SPT in which the traditional SPT is complemented by a torque measurement after driving the split spoon to give a more direct measurement of side resistance between the soil and the spoon. SPT-T tests performed at a number of sites demonstrate that the results obtained from the SPT-T may be used to estimate pile side resistance much in the same way that the CPT "friction sleeve" is used. The results show a direct correlation between SPT N60-values and unit side resistance. This is consistent with observations reported in the literature relating N to side resistance of full scale piles. The results are used to provide some reasoning for the apparent correlations reported in the literature and suggest that theSPT-T can be a valuable test for making preliminary estimates of pile side resistance.
In this study, a series of laboratory modeling testing is presented to study the shear strength of the soil using static load test performed in a prototype Static Standard Penetration Test (SSPT) tank. Static Standard Penetration Test (SSPT) is a new combination method of Standard Penetration Test (SPT) and Cone Penetration Test (CPT) to obtain an undisturbed sample. The difference is that SPT is driven by blows using the dynamic force to penetrate the sampler into the soil. SSPT is applying the measured force to the rod where the sampler is pushed into the soil continuously using static force at a uniform rate of penetration to collect sample. The transducer and the load cell will be connected to the computer to record every second of time, depth of penetration of the sampler and measured force for the sampler to penetrate into the soil. Subsequently, an analytical formula for determining the shear strength of soil has been developed from the result of unconfined compression test (UCT). It is shown that the formula to determine the shear strength of the soil can be reasonably used.
