Inscrivez-vous ou connectez-vous pour rejoindre votre communauté professionnelle.
<p>The rectification of RCC structure is a time and money consuming process. Even then, due to EQ damages, the monumental buildings, ought to be retrofit. In doing so, the design principle "Strong Column and weak beam" theory is to be followed scrupulously. </p>
This phrase is only a practical way for describing how is supposed to fail a RC’s building, in case of earthquake, in order to reduce the damages and injuries:
The idea is that the beams and horizontal elements of the structure should break, (without total collapse if possible, just breaking = creating plastic joints) always before the columns, and, even better, the beams in the upper levels should break always before the beams of the lower levels, creating a cascade effect that helps to the structure to dissipate better the seismic energy without the total collapse. By the creation of these plastic joints in the beams, the initial ductility of the untouched structure , now partially broken, increases enormously, and can absorb bigger amount of lateral displacements, vibrating like a multiple inverted pendulum. (Better the structure useless after the earthquake but without personal injuries, than the opposite).
How to do this in a practice way?
Well, if you are using like reference a well-established country code for calculating the structure and its members ( Eurocodes, ACI, etc, ), it is supposed that by doing all the things as per the code, without mistakes, you are reaching this result.
This always means to select well the parameters of the seismic loads in function of the shape and other characteristics of the building, the area of the world and its seismic parameters (Seismic wave speed, Seismic Spectrum, etc..), the geological characteristics of the ground, the historical records of earthquakes, distance of the location of the building to the most likely center of the earthquake, etc., etc.( all the country-codes have all these considerations into account for calculating the inertial loads), you do well the calculation of the inertial distributed loads over the RC members, by using the appropriate software without mistakes, and also you take care of doing the design of the steel reinforcement of the Concrete following the rules for this case( rules for distributing extra steel bars and stirrups, for increase the overlapping lengths and anchor length, and doing the overlapping in the recommended zones of the RC members ,using the steel with the best ductility characteristics, confining well the concrete ,etc., etc.,. ) , you will get this for granted.
