Gabriel L. Stockdale¹, and Gabriele Milani¹
1)  Dept. of Architecture, Built Environment and Construction Engineering, Politecnico di Milano
Piazza Leonardo da Vinci 32, 20133 Milan, Italy
email: {gabriellee.stockdale, gabriele.milani}@polimi.it

Keywords: Masonry arch, Limit Analysis LA, Interactive analysis, AutoLISP®, AutoCAD®, MATLAB®.

Abstract. Efficiency in structural analysis and assessments is economically critical. The coupled nature between capacity and geometry for masonry arches often hinders this efficiency. This work utilizes a data extraction technique and limit analysis tool developed from an equilibrium approach to the kinematic theorem to provide an interactive analysis of any arch drawn in AutoCAD® and subjected to constant horizontal accelerations. The geometric data of the arch is extracted from the AutoCAD® drawing via a custom command developed with AutoLISP®. A simple app created in MATLAB® then loads the extracted geometry data, calculates the collapse load multiplier and hinge reactions for a random kinematically admissible mechanism, and plots the resulting thrust line required to maintain a zero moment at the hinges. The hinge locations can then be adjusted with the collapse condition, reactions and the thrust line are recalculated for any defined and kinematically admissible hinge set.