BEARING CAPACITY DETERMINATION OF SANDY SOIL LAYER USING LIGHT WEIGHT PENETRATION TEST
Abstract
The objectives of this study is to investigate the effect of the 3 apex angles of cone and ground water tables on the bearing capacity of sandy soil layer by using light weight penetration test. Silty sandy soil (SM) was provided as the representative of sandy soils for some area in Thailand. The SM soil layer was prepared in the testing tank and also set three depths of ground water table for testing . According to results, the cone angle increase, a number of blows increase and the adjusted factors of the blows from the apex angles of 60º and 180 º to be that of the apex angle of 90º (control) were 1.118 and 0.878, respectively. The obtained correlation between the blows and the internal friction angles of SM soil can be used for calculating the soil bearing capacity which lowers the ground surface of 0.6 m. The soil bearing capacity of SM soil below ground water level decreases 70 to 75 percent (average values from testing results) comparing to that of dry soil. Moreover, bearing capacity of SM soil above ground water table up to 0.6 m decreases 25 to 30 percent (average values from testing results) comparing to that of dry soil at the same depth. The SM soil layer was lower bearing capacity due to higher ground water table. Therefore, bearing capacity determination of silty sandy soil layer should be also considered the effect of ground water table.
References
Kererat, C. (2012) “Manual of soil mechanics laboratory” Rajamangala University of Technology Rattanakosin, Prachuap Khirikhan.
Khuwijitjaru, S. (1999) “Soil Laboratory Testing”, Library Nine Publishing, Bangkok.
Khuwijitjaru, S. (2001) “Soil Investigation: Boring, Sampling and Field Test” Kasetsart University Press, Bangkok.
Krasaeteep, A. and Thongchart, S. (2012) “A Comparison of Cone Tip in Kunzelstab Penetration Test (KPT)” the 17th National Convention on Civil Engineering, Udonthani.
Meyerhof, G.G. (1956) “Penetration Tests and Bearing Capacity of Cohesionless Soils” Journal of the Soil Mechanics and Foundations Division, 82 (1), 1-19.
Sakmanee, A. and Chantawarangul, K. (2003) “Soil exploration by dynamic light penetrometer” the 41th Kasetsart University Annual Conference, Bangkok, pp. 490-497.
Sakmanee, A. and Chantawarangul, K. (2006) “Dynamic penetrometer resistance in sand” the 11th National Convention on Civil Engineering, Phuket.
