STRUCTURAL ANALYSIS OF THE MASSIVE ADOBE PYRAMID OF HUACA DE LA LUNA, PERU UNDER GRAVITATIONAL AND LATERAL ACCELERATIONS
Selman Tezcan, PhD candidate, supervised by Renato Perucchio
Friday, February 19, 2021
Huaca de la Luna is a monumental religious complex located in the North coast of Peru built in different stages from 100 AD to 650 AD by the Moche civilization using millions of adobe blocks. The specific focus in this study is the main stepped pyramid at the center of the complex. Built on the slopes of the Cerro Blanco mountain, this massive structure consists of the superposition of horizontal platforms added on top of each other during historical renovations. On the east side the pyramid is supported on solid bedrock while the west side is built directly on layers of soft sand, with large adobe blocks serving as the foundation layer. The pyramid presents severe structural damage near the north-west corner. In this study, the static and dynamic response of the pyramid is analyzed using 2D plane strain FE models representing the east-west cross-section positioned in the middle of the pyramid together with the underlying soil profiles. The nonlinear FE analysis is performed in Abaqus/CAE Explicit using the concrete damaged plasticity and the Mohr-Coulomb formulations for modeling adobe bricks and soils, respectively. We perform a sensitivity analysis of the static and dynamic response to (a) the pyramid stepped west side profile, (b) the underlying soil and bedrock configuration, and (c) the adobe material tensile strength. The time-evolution of strain, kinetic, and dissipative energy (due to plastic deformations simulating internal fractures) is used to identify the development of local damage conditions up to the structural collapse of the pyramid west side. Lateral accelerations, applied at the bedrock level after gravitational loading and as a linear function of time gradually increasing from 0 to 0.2 g, indicate that the west side suffers complete collapse under 0.135 – 0.2 g for all the architectural/soil/material configurations considered.
Meeting ID: 991 8415 3547