This blog presents a case study with using PileLAT program for a pile lateral load test carried out in Salt Lake City in 2003. Figure 1 shows the testing layout and Figure 2 shows the testing arrangement as reported by Rollins et al. (2003).
Figure 1 Single pile lateral loading test layout (from Rollins et. al. 2003)
Figure 2 Single pile lateral loading test arrangement (from Rollins et. al. 2003)
The test single steel pipe pile had an outside diameter of 324 mm and a wall thickness of 9.5 mm. The modulus of elasticity for the steel is 200 GPa. The moment of inertia (I) of the pile is 1.17 x 10^8 mm^4.
Considering the angle irons attached to the pile in order to protect the instrumentation, the inertia moment of 1.43 x 10^8 mm^4 is adopted in the analysis as recommended in Rollins et al. (2003). The pile was driven to a depth of approximately 11.9 m below the excavated ground surface.
The pile was loaded using a hydraulic jack that reacted against the pile cap constructed around the adjacent pile group after it had been load tested as shown in Figure 2.
The soil profile consists of stiff clays with some sand layers underlain by soft clays. The water table was located 1.3 m below the excavated surface. The average unit weight of soil was 14.93 kN/m^3. The adopted soil profile in the analysis with using PileLAT program is shown in Figure 3.
Figure 3 Ground profile and soil parameters in the analysis with using PileLAT
Figure 4 shows the plot of later load versus deflection at the pile head. The results from PileLAT analysis are plotted with red color. The measured data together with the analysis results with using LPile and FLPier as reported by Rollins et al. (2003) are also included for comparison purposes. It can be seen that the prediction from PileLAT is very close to the testing results and the analysis results from both LPile and FLPier.
Figure 4 Comparisons of pile head load deflection curves from different methods