Joining Fragmented Epistyles Using Threaded Titanium Bars: A Numerical Analysis

Abstract

The mechanical behaviour of marble architraves, restored with titanium bars and suitable cementitious material, is studied with the aid of the finite‐element method. The study was motivated by the needs of the conservation project in progress on the Parthenon Temple of the Acropolis of Athens. A realistic numerical model was created taking into account the exact geometry of the threaded bars as well as the exact mechanical properties of the materials involved. The architrave was considered as a prismatic beam of rectangular cross section, centrally fractured and restored with one threaded titanium bar. The bar was inserted in a hole of slightly greater diameter drilled in the member and filled with suitable cementitious material. In this way, a sequence of three materials appears (marble–cement–titanium) giving birth to two interfaces (marble–cement and cement–titanium). Emphasis was given to the influence of the cement layer on the stress and strain fields. The cement was modelled as either linear or bilinear material and the analysis indicated the crucial role of this layer for the drastic reduction in the strain discontinuities.

Criterios Para El Refuerzo Antisísmico De Estructuras

“…Recientemente se ha comenzado a hacer un mayor uso de otros metales de mayor durabilidad y compatibilidad, como el titanio, debido a que su costo se ha reducido. Un ejemplo es el caso de la Acrópolis en Atenas, donde se han usado barras de titanio para el refuerzo de las arquitrabes (Ganniari-Papageorgiou, 2009). Las intervenciones en donde se ha usado concreto y mortero de cemento portland han mostrado problemas significativos de compatibilidad cuando se encuentran estos materiales en contacto directo con mamposterías históricas de piedra o tabique (Calderini, 2008).…”

Experimental and numerical study of a fractured marble epistyle restored with layers of titanium bars

“…Recently the reinforcement method was assessed both experimentally and numerically [6][7][8][9][10]. The analyses revealed the critical regions, where the maximum stress and strain discontinuities appear and enlightened the influence of the geometrical characteristics of the reinforcing bars and the crucial role of the constitutive law governing the mechanical behaviour of the intermediate layer of cementitious material.…”

“…In this direction a more thorough experimental and numerical investigation of the problem of restoring symmetrically fragmented epistyles is undertaken in the present study. The main target is the validation of previous numerical models [7][8][9][10] and the quantification of the influence of some critical parameters related to the reinforcing bars (number of bolted titanium bars, thread shape, anchoring length).…”