Verification of a masonry structure, end to end.
Pin the site, choose the materials, model the structure. SMART masonry covers the full NTC 2018 + Circolare 2019 calculation flow: site-resolved actions, equivalent frame, gravity loads, modal analysis, global pushover, out-of-plane local mechanisms.
Site-driven actions
Drop a pin in Italy and SMART masonry resolves the seismic, wind and snow action parameters automatically, cutting the strictly-manual work down to almost nothing. Province and region, height above sea level, distance from coast, seismic hazard and zone — all derived automatically.
Resolved automatically from one pin
- Province, region and comune (ISTAT polygons)
- Elevation above sea level
- Distance from coast (with minor-island detection)
- Wind zone and exposure category
- Snow zone and altitude-corrected qsk
- Seismic hazard (GNDT grid)
Masonry characterisation
Masonry constitutive parameters come from two distinct chains: existing or new masonry.
Existing masonry
Pick a typology (e.g. roughly-shaped stone, solid brick with lime mortar) and a knowledge level (LC1 / LC2 / LC3). Tab. C8.5.I seeds the six mechanical properties; Tab. C8.5.II layers the intervention coefficients on top — buona malta, regular brick courses (ricorsi), systematic transverse connections, consolidamento (iniezioni, intonaco armato, ristilatura armata), artificial diatons.
New masonry
Pick the block type, mortar class M and unit characteristic strength fbk. The engine interpolates Tab. 11.10.VI / VII for fk and Tab. 11.10.VIII for fvk,0; the moduli follow NTC §11.10.3.4 (E = 1000·fk, G = 0.4·E).
Macro-element model
Walls are treated as an assembly of piers (the masonry between openings) and spandrels (the masonry above and below openings), connected by rigid nodes — the equivalent-frame approach explicitly endorsed by NTC 2018.
Piers and spandrels are modelled as Timoshenko 2-node beams with rigid end-offsets. They develop plastic hinges in compression-bending and a plastic shear hinge in shear, both with displacement-controlled damage.
3D consistency is obtained by connecting walls through deformable floors, modelled as orthotropic membrane elements.
Heterogeneous degrees of freedom
Full 3D node carrying mass. Connects non-collinear walls to each other and walls to floors.
In-plane to a wall alignment only. Guarantees each wall contributes stiffness and strength in its own plane. Vertical loads land here.
Horizontal translation only. Belongs to floors alone (balconies, openings in slabs).
Wall self-weight is split half to the bottom-level node and half to the top-level node of the panel it belongs to, so the gravity-load path mirrors the geometry.
Non-seismic load analysis
Gravity-load analysis runs as a load-controlled static. It provides the axial-load demand on each wall and is explicitly designed to avoid unphysical vertical-load transfers between non-collinear walls.
Compression and out-of-plane stability are then checked strictly against NTC 2018 §4.5, including the effective-height factor ρ and the Φ stability correction.
Modal analysis
Modal analysis runs on the same 3D macro-element model by solving the dynamic eigenproblem K · φ = ω² · M · φ. Periods, mode shapes, participation coefficients and participating mass ratios are evaluated from the solution of the problem via the Lanczos shift-invert algorithm.
Seismic nonlinear static analysis
The analysis runs in two steps. First, vertical loads in the seismic combination are applied with the same per-wall approach used in the non-seismic analysis, in a static load-control pass. Then 24 seismic combinations are generated and each runs a nonlinear pushover with indirect displacement control. The controlled displacement defaults to the top-storey mass centre; however, the user can select the mass centre of a different level (for example, when small rooftop towers are present).
24 combinations, run in parallel
- 2 load distributions: proportional to mass, first-mode shape
- 4 directions: ±X, ±Y
- 3 accidental eccentricities: none, +5%, −5%
During each analysis, plasticisation is monitored together with partial or total damage on piers and spandrels. Damaged elements unload and the residual action redistributes to the neighbours. Piers are checked in compression-bending (rocking and toe-crushing) and in shear under the user-selected criterion (Turnšek–Čačovič or Mohr–Coulomb); spandrels follow analogous criteria from Circolare 2019.
On each base shear vs. controlled-displacement curve the capacity limit states are identified. The structure is then reduced to an equivalent elastic-plastic SDOF system: the displacement demand for each limit state is read from there, and the verification index ζE is produced.
Out-of-plane local mechanisms
In-plane pushover is only half of the seismic story: a wall can overturn out of its own plane before the global structure reaches its capacity.
SMART masonry follows a unique approach: the wall's transverse section is modelled as rigid blocks interacting through nonlinear elastic-plastic interfaces (no-tension, no-sliding, finite elasticity and optional finite compressive strength). Rather than postulating a predefined mechanism (e.g. simple overturning), an out-of-plane pushover is run on the block assembly and the weakest mechanism activates automatically.
Geometric nonlinearities are handled with a co-rotational formulation, so the full overturning of a block can be traced correctly, as required by the nonlinear kinematic analysis of Circolare 2019.
