  Numerical modeling using computers is known to present several advantages
compared to experimental testing. The high cost and the amount of time required
to prepare and to perform a test were among the main problems on the table when
the first tools for modeling structures in fire were developed. The discipline
structures-in-fire modeling is still currently the subject of important
research efforts around the word, those research efforts led to develop many
software. In this paper, our task is oriented to the study of fire behavior and
the impact of the span reinforced concrete walls with different sections
belonging to a residential building braced by a system composed of porticoes
and sails. Regarding the design and mechanical loading (compression forces and
moments) exerted on the walls in question, we are based on the results of a
study conducted at cold. We use on this subject the software Safir witch obeys
to the Eurocode laws, to realize this study. It was found that loading,
heating, and sizing play a capital role in the state of failed walls. Our
results justify well the use of reinforced concrete walls, acting as a
firewall. Their role is to limit the spread of fire from one structure to
another structure nearby, since we get fire resistance reaching more than 10
hours depending on the loading considered.
