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This paper addresses the problem of sustainability in remediation, retrofit, and seismic upgrading of historic masonry structures. Different rehabilitation techniques and some successful applications throughout the Balkans and Italy are described, with particular emphasis to the shear reinforcement of wall panels. The selected techniques aim at improving the seismic performance, preserving the structures for future generations, having the least impact in altering the architectural and heritage values, as well as being sustainable, in terms of reduced carbon dioxide emissions, reversibility, and low energy consumption. The use of cross-laminated timber (CLT), natural fibers, and fiber-reinforced Polymers (FRP) jacketing with natural lime coatings are discussed. The paper concludes by summarizing key successes of the proposed rehabilitation solutions in conservation engineering and suggests areas in which these could be used with great advantage. [ABSTRACT FROM AUTHOR]

This paper presents the results from a combined experimental and advanced computational study to understand the dynamic response of a pultruded fiber-reinforced polymer (FRP) sheet pile of 9 m length that is installed into the ground near Venice, Italy. The peak embedment force of 10 kN is applied at the top as a sinusoidal compression force having a maximum frequency of circa 760 Hz. Physical measurements from accelerometers are reported for the lateral deformation response of a single sheet pile and of a unit restrained by an installed waterfront barrier. A finite-element modeling methodology for the two test configurations is developed by using the Strand7 code, so that advanced computational results can be compared against the field application measurements. Closed-form equations for the fundamental frequency are developed, with one accounting for the presence of rotary inertia and shear deformation. Dynamic responses at different embedment lengths (1-7 m) are examined, and a very good correlation is found between theory and practice. Numerically, the performance of the FRP sheet pile is compared with the response of a fictitious sheet pile of steel and with two new FRP geometries that increase stiffness to minimize flexure about the minor axis of bending. By increasing the mass by 10%, the maximum lateral displacement can be the same as the steel unit and 1/20 of the tested FRP unit. Findings of the research demonstrate that the FRP unit can be installed by using the same pile driving rig and procedure for steel sheet piling. [ABSTRACT FROM AUTHOR]

The oldest cast iron arch bridge built in 1852 in Venice exhibits serious deterioration due to corrosion and cracking of its members. The Municipality accepted a proposal to strengthen it with Aramid fiber reinforced polymers (AFRP) materials. The AFRP materials application aims to arrest cracks and reduce the structure’s vulnerability to impact by boats. Tests have already been performed on structural cast iron beams taken from similar cast iron bridges dismantled. Results from four point bending tests showed an increase in strength and a different fracture mode depending on FRP application. Charpy tests showed an increased fracture energy in specimens strengthened with FRP and primer. Utilization of bidirectional and triaxial fabrics was discussed. However this paper is particularly focused on nondestructive testing following the FRP application. Nondestructive testing has been planned both for laboratory test specimens and for a long term monitoring program. Artificial defects, embedded during manufacturing in some test specimens, have been analyzed using the pulsed echo ultrasonic technique, in order to compare the resolving power of different ultrasonic frequencies and probe arrangements. Furthermore, a long term monitoring program has been planned in order to assess bonding performance using ultrasonic and pulloff tests on the overall strengthening and on some test specimens placed in the same environment. [ABSTRACT FROM AUTHOR]

In this paper a recent rehabilitation project completed in Italy using carbon fiber reinforced plastic (CFRP) unidirectional sheets is examined. This technology was selected for the strengthening of a doubly curved, precast, prestressed concrete (PC) shell. The shell was part of the roof of an industrial building and had experienced severe localized damage due to accidental heat radiating from a flue. The selection of the CFRP system involved the screening of different repair procedures with relation to the constraints imposed by the owner: limited disturbance to the industrial process, safety of the occupants, low cost, and durability. In addition, the damaged PC shell was located in the center of the industrial building and did not allow the use of a crane for its replacement. This project demonstrates that the utilization of new materials can provide owners/designers with effective solutions to challenging restoration problems. [ABSTRACT FROM AUTHOR]