Structure: Private, detached building for residential use, built in 1900 and expanded to the east and west in 1980. The building, located along a gentle flat hill ridge, is located at Strada San Germano, No. 100 in Tavullia (PU) and consists in the central portion of two above-ground floors and an attic and in the extensions of one above-ground floor and an attic with basement present only in the northeast corner of the extension. One-story garage. The vertical structure of the 1900 body is of solid brick masonry while the extensions are of load-bearing blocks, partitions of perforated brick blocks, and floors and roofing of late concrete.
Foundations: of continuous type, direct in weakly reinforced limestone with the presence of bricks and stones placed at a depth varying from 0.80 to 2.00 meters from the floor level.
Disturbance: visual analysis of the building showed, in each area, but with greater prominence in the southeast corner, along the west elevation, and in the north elevation of the garage, a network of lesions with sub-vertical, sub-horizontal, and inclined courses. The crack pattern, with tensile failures, was produced by shear and bending stresses corresponding to anticlinal deformations with a hinge axis in the median zone of the 1900 structure spine wall (north-south direction). This observation classifies the failure as terminal differential vertical translation for total height. The garage shows a lesion network with vertical, horizontal and inclined traces. The crack pattern, with tensile failures, was produced by shear and bending stresses, corresponding to asymmetrical deformations. This observation classifies the failure as differential vertical translation. The floor reveals subsidence of greatest evidence in the west (billiard room and study). The subsidence began before 1990 (the date the current owners purchased the structure) and has progressively worsened, particularly in 2016, due to prolonged drought period.
Soil: from the preliminary geological report in December 2017, it appears the presence, below ground level, of topsoil and/or alteration soil, with base formation composed of marly clay altered to hazel-colored and compact sandstones attested at about – 1.20 mt from the ground level. The surface clay lithotype is subject to phenomena of volumetric shrinkage and contraction by drying with subsequent swelling as a result of seasonal climatic and rainfall trends. Phenomena that are accentuated by the action of dewatering exerted by the suction of tree roots in the vicinity of the building, in leaks and/or dispersions of water or sewer systems and in the improper regulation of downpipe drainage water; for the above-mentioned phenomenologies, careful verification and eventual, prompt restoration is recommended.
