CIS STRUCTURAL RESISTANCE CERTIFICATION

The structural resistance certificate of a building is a document drafted in conformity with the Italian Ministerial Decrees 15/05/1985 and 20/09/1985, which attest to the safety conditions of support structures of a building, according to laws in force at the time of construction.

This document is indispensable to obtain the certification declaring that a building complies with safety standards, in cases when it is not possible to recover it or there is no certificate of a static resistance audit or to complete the amnesty application.

Controls for the issuing of the CIS

The professional charged with the controls necessary for the issuing of the CIS must:

• Study the building;
• Know when it was built and when any potential successive interventions were carried out;
• Carry out surveys on site to verify the conditions of the foundations and the land, verifying if there are cracks, fissures, settling, or signs of a previous or forthcoming instability.
• Analyse the materials to ascertain their solidity.

CIS Contents

The static resistance certificate, from a formal point of view, is generally structured as follows:

• The personal data of the professional in charge, including address and contact information;
• Indication of the subject who hired the professional;
• Location, land registry data, destination of the building;
• Description of the building, the materials used for its construction and for successive works;
• Description of the structural elements of the building;
• Data of surveys and studies and load tests conducted;
• Data relative to the static resistance of the buildings;
• Conditions of fissures and decay;
• Geological surveys
• Certification of the static resistance condition of the building. If the building is suitable from a static viewpoint, the technician will be limited to ascertaining the safety conditions and soundness of the building that support his conclusions. On the contrary, the technician is obliged to indicate which interventions would be necessary to render the building statically safe.

Who to contact to draft the seismic resistance certificate

To obtain this document it is necessary to contact a professional, usually a civil engineer or building engineer specialised in structures, registered with his/her own professional or trade organisation. Unlike the static resistance audit, the drafting of which requires that the professional be registered with his professional or trade organisation for at least 10 years, there are no limits for the declaration of static resistance. For the static resistance certificate no seniority for the registration in a professional or trade organisation is required.

BUILDING SEISMIC VULNERABILITY TEST

The procedures for the assessment of seismic vulnerability of the buildings can be conducted with different levels of in depth analysis and complexity of calculations: from more qualitative estimates, based on detection by means of tables of the main characteristics of the structural elements of the building, to complex numerical analyses by means of linear and non-linear calculation methods.

How to assess the vulnerability of a structure

The seismic vulnerability of a structure is represented by an indicator that compares the resistance capacity of a structure and the demand in terms of resistance and/or movement of the seismic event.
The procedures for the assessment of seismic vulnerability of the buildings can be conducted with different levels of in depth analysis and complexity of calculations: from more qualitative estimates, based on detection by means of tables of the main characteristics of the structural elements of the building, to complex numerical analyses by means of linear and non-linear calculation methods.
All of the assessment procedures are based on the completion of paper forms and lead to a preliminary evaluation. These results can be used to establish an order of priorities for potential compliance/improvement interventions.

The estimate of the overall seismic vulnerability of a structure for the purposes of drafting a structural project for seismic improvement/compliance must be attained by performing structural calculations coherent with the analysis methods outlined by Technical Codes for Constructions.