Abstract:The performance of laterally loaded piles is often obtained via in situ lateralpile–load tests. In general, inclinometer measurement is routinely used in these lateralpile–load tests. In an effort to develop an efficient method for interpretation of lateralpile–load test results via measured inclinometerdata only, an analytical model is proposed based on the energy conservation of the pile–soil system. A Fourier series function is used to represent the deflection behaviour of the pile–soil system. To obtain the shear, moment and soil reaction along the pile shaft, convergence of the series after differentiation is guaranteed by applying the Cesaro sum technique. Three full-scale lateralpile–load cases are then used to verify the feasibility of the methodology developed, as well as to make comparisons with other methods.