Rafael Shehu

• PhD
• Lecturer at Politecnico di Milano

The role played by inclination in both the load carrying capacity and seismic assessment of masonry bell towers is investigated through the results obtained from different analyses on three case studies. The Italian Code for the built heritage is not explicit about the influence of inclination on the seismic assessment of towers, leaving to practit...

The use of fiber reinforced polymers (FRP) represents an interesting option to inhibit the formation of partial collapse mechanisms on macro-blocks, which is a typical failure mode shown by masonry churches under seismic actions. Furthermore, FRP strips exhibit a very good performance at failure, low invasiveness and high speed of execution. This s...

In the last decades, the possibility to use the inelastic capacities of structures have driven the seismic design philosophy to conceive structures with ductile elements, able to obtain large deformations without compromising structural safety. In particular, the utilization of high-strength elements combined with the purpose of reducing inertial m...

Three inclined historical masonry towers, located in the city of Ferrara (North-East region of Italy), are analyzed under seismic loads employing advanced numerical models. This study provides a critical review on the conservation state, present vulnerabilities, influence of peculiar structural features, and future need for strengthening interventi...

Seismic assessment is a paramount issue and a valuable instrument towards the conservation of vulnerable structures in seismic prone regions. The past seismic events have highlighted the vulnerability of masonry towers that is exhibited by severe structural and nonstructural damages or even collapses. The preservation of existing structures, mainly...

A building’s level of seismic performance remains the greatest concern for engineers and researchers in seismic-event-prone countries [...]

Masonry towers are peculiar structures with complex structural behavior despite biased conclusions deriving from their geometrical regularity and simplicity. Their geometrical features and the epistemic uncertainty that masonry material bears strongly influence their static and seismic behavior. This paper investigates a remarkable and representati...

Two earthquakes struck the NW region of Albanian territory on 21 September 2019 (Mw = 5.6) and on 26 November 2019 (Mw = 6.4). The epicenters of the seismic activity were located offshore NW Durrës, one of Albania's most populated cities, located 30 km from the capital Tirana. Various aftershocks followed subsequently. While there were no reported...

Concrete is one of the construction industry’s most essential and commonly used materials [...]

The resilience of a community to come across the natural hazard events is gaining popularity in planning and decision-making strategies. To utmost importance in seismic zones, is the safety and operability of structurally vulnerable existing structures, representing a high portion of the built stock. Manifested low resilience has shown many flaws i...

The paper provides an insight into the seismic strengthening of masonry towers with horizontal and vertical steel rods by means of a limit analysis approach. The kinematic theorem of limit analysis with five pre-assigned failure mechanisms, observed during post-earthquake surveys, has been implemented for different geometries of idealized towers, a...

The paper gives a preliminary insight into the seismic vulnerability of bell towers, discussing a real case study, namely a masonry tower built in XIX century and located in the Province of Venice (Italy). Such case study is fully investigated using different advanced FE strategies. The case study shows structural features often common in other cas...

The paper gives a quantitative insight into the vulnerability of existing masonry chimneys located in Spain, accounting for horizontal loads, geometry and material deterioration. During the past two centuries, the industrialization process gave rise to a quick increase in the construction of chimneys, which were made almost exclusively by brickwork...

The paper provides an insight into the seismic strengthening of masonry towers by means of horizontal and vertical steel tie-rods. The approach is based on the kinematic theorem of limit analysis with pre-assigned failure mechanisms. Among all the possible ones, five of them commonly observed during post-earthquake surveys are selected: (#1) vertic...

The paper presents some numerical results on a Romanesque masonry church located in Emilia-Romagna (Italy), a region recently stricken by a devastating seismic sequence on 20th - 29th May 2012. A full investigation of the damages and their comparison with advanced FE analyses, in both linear and nonlinear range are carried out. FE limit analyses ar...

This paper presents some advanced FE analyses conducted on a masonry church damaged by the recent Emilia earthquake, occurred on 20th-29th May 2012. The Nativity of the Virgin Mary parish, located in the province of Ferrara (Italy), was subjected to a post-earthquake strengthening intervention, which consisted of introducing steel profiles, rigid d...

The paper presents some FE analyses conducted through advanced techniques for the seismic assessment of existing masonry towers. Traditionally, masonry towers were conceived to withstand vertical loads only, but in recent years national and international standards have imposed the evaluation of their structural performance even in presence of horiz...

This paper investigates the effectiveness of reducing the seismic vulnerability of masonry towers by means of innovative and traditional strengthening techniques. The followed strategy for providing the optimal retrofitting for masonry towers subjected to seismic risk relies on preventing active failure mechanisms. These vulnerable mechanisms are p...

The paper presents some seismic analyses on three masonry churches located in Emilia-Romagna (Italy), recently stricken by a devastating earthquake sequence from 20th to 29th May 2012. These churches have a similar geometrical configuration, consisting of three naves, a central colonnade and a simple apse. Limit analyses are conducted on the most i...

This study presents some FE results regarding the behavior under horizontal loads of two existing masonry towers located in South-East Lombardy, Italy. The towers, albeit unique for geometric and architectural features, show some affinities that justify a comparative analysis, as for instance the location and the similar masonry material. Their str...

This paper presents some preliminary results from the numerical investigations of different interventions for the seismic upgrading of a masonry bell tower. Masonry bell towers belong to the cultural and historical heritage, are very widespread in Italy and their conservation has been given special attention in recent years. Their high vulnerabilit...

The paper presents some preliminary results of advanced Finite Element (FE) analyses on the upgrading of old masonry constructions by means of Fiber Reinforced Polymers (FRPs). The case study is a masonry Romanesque church, located in Ferrara, Emilia Romagna (Italy). The church exhibits widespread damage caused by the recent earthquake sequence occ...

Four inclined masonry towers are investigated in this paper in order to study the behavior under horizontal loads and the role of inclination on the seismic vulnerability. The towers are located in the North-East of Italy, a moderate seismicity region that was recently stricken by an earthquake with two major seismic events of magnitude 5.8 and 5.9...

This paper presents some preliminary results of seismic analyses performed on a masonry church located in Emilia-Romagna (Italy). The church suffered damage during the seismic events occurred in 2012 and some seismic upgrading interventions by means of Fiber Reinforced Polymers (FRPs) are proposed. The behavior of the church is investigated under h...