Numerical Testing of a Small-Scale Stone Masonry Arch

Abstract

IntroductionMaintenance and restoration are common problem of historical stone structures. There are more than 1500 stone masonry arch bridges in Hungary which were built primarily in the 18th and 19th centuries [1]. Since the condition of most bridges aggravated and the traffic loads have increased significantly, the verification of the stability and the calculation of the load-bearing capacity of these bridges are required. Thus several Hungarian stone masonry arch bridges were investigated in the past few years [2-9]. It has been found that it is difficult to determine adequate input parameters for the numerical modelling from the in situ tests even for simple methods such as thrust line analysis. Naturally, the more complex methods require more precise input parameters. Nonetheless, the results of these more complex models describe better the behaviour of the masonry vaults. All things considered, great accuracy is expected from the numerical models, though it is not attained in case of practical applications. In general, it is very difficult to obtain the input parameters which can modify the results significantly. Therefore it is important to determine the scale of these effects and get to know their behaviour better by means of laboratory and numerical experiments.Within the masonry vaults predominantly compression, and in a smaller extent shear and friction occur from the external loads. The main point in design of arch geometries is to allow the smallest tension to occur, since the connections of real masonry arches usually do not resist high tensions. If a vault is capable of bearing a significant tensile stress, then it is a continuum shell rather than a masonry shell. Thus the bonding strength of the connections influences the behaviour of the arches significantly. In case of small scale laboratory experiments the bonding strength has a more important influence on the stability of the structure. As a consequence, this parameter was analysed by means of numerical modelling.The aim of this paper is to provide information about the required parameters for the analysis of the behaviour of stone arches by means of experiments. To increase the reliability of models and to have a better accuracy of the input parameters scale laboratory experiments are required with the combination