PSI - Issue 11

Roberto Scotta et al. / Procedia Structural Integrity 11 (2018) 282–289 R. Scotta et al. / Structural Integrity Procedia 00 (2018) 000 – 000

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Thanks to the high level installation accuracy of the bottom rail, the assembling of the buildings and the waterproofing were easier, faster and more reliable in comparison with traditional techniques. During the installation of the structures, no difficulties and delays due to geometric inaccuracies in the foundations occurred. In the meantime, the durability of the wooden panels was assured. 6. Proposal for restoring rottenness at the base of existing buildings The innovative bottom rail described above could be used also to restore damaged parts at the base of timber walls, by removing the deteriorated material, realizing in the same position a new RC curb (if not yet present) and interposing the aluminium beam between the healthy part of the wall and the RC curb. This intervention may be applied only in the damaged parts or at the base of all the walls of the building. Fig. 9 shows main phases to realize the intervention as described below. PHASES 1-2 PHASE 3

PHASES 4-5

PHASES 6-7

Fig. 9. Installation phases in the case of restoring damages to existing buildings

1. Removal of some rectangular portions of the base of a wall, alternating them with residual portions of damaged timber to support the entire wall. In this phase, particular attention shall be paid to realize a straight cutting, installing a horizontal rail in the panel to keep the saw parallel to the wall base. If cutting is not perfect epoxy resin can be added to fill the gap; 2. Arrangement of grouting rods to anchor the new RC curb to the existing slab, with spacing and diameter depending on lateral loads (i.e., due to earthquake and wind); 3. Arrangement of horizontal steel rebars and vertical stirrups for the realization of the new RC curb, with spacing and diameter depending on tensile and shear forces to be transferred from the wall to the foundation; 4. Arrangement of aluminium beams, between the healthy wall base and the steel rebars of the new curb. Anchoring of brackets to the aluminium beam, using the lateral groves described in Section 3, and in the timber wall with nails. Installation of vertical concrete anchors to fix the brackets to foundation and to guarantee a perfect contact between the aluminium beam and the healthy wall base. At the end of the intervention, brackets and anchors will confer resistance to shear and tension forces due to lateral loads. However, in the following phases (5 to 7), they will act as support for the entire wall, resisting vertical compression. It is worth noting that these anchors can have length equal to the height of the new curb or can be also partially grouted in holes in the RC slab, depending on the expected uplift forces due to wind or earthquake; 5. Removal of the remaining portions of damaged timber. The wall is supported by the brackets and the concrete anchors described in phase 4;