【正文】 ase of cylinder if the ductility insufficiently has the destruction to be very easy to cause the structure whole to collapse. These disadvantage factors caused this method to lose the very big superiority.Therefore does not need to limit by the mechanics of plasticity organization concept below, so long as can realize the plasticity under the big quake to consume energy the organization, can guarantee the earthquake resistance design the basic request:(1) Consumes energy by the beam end plastic hinge primarily.(2) Does not limit the column end plastic hinge to appear (including first floor base of cylinder), but enable it through the suitable enhancement column end anti curved ability method to have the enough allowance under the big quake plastic rotation to its plastic rotation ability.(3) The end at the same time is not at the plastic deformation condition with the level various columns about.In our country39。s earthquake resistance measure to consumed energy the organization consideration also basically to follow this mentality, has used the beam column plastic hinge organization the pattern.In earthquake resistance design we in order to avoid not having the ductility shearing failure the occurrence, took strong cut weakly is curved the measure to process the ponent to bend the ability with to cut the ability the relational question. The worth noting is, with must resists earthquakes anti cuts the destruction to pare, under the earthquake function shearing failure is different. Take the beam ponent as the example, under the big earthquake function, the beam end forms alternately the slanting crack area, this area concrete the slanting crack division, is formed certain diamonds block body, moreover destroys can grow along with the ductility but intensifies. As a result of alternately the slanting crack and the plastic hinge area basic superposition, vertical and the slanting crack opening can but increase along with the ductility. Under the earthquake resistance acts according to the beam end the stress characteristic, the positive shear always is bigger than the negative shear, under the positive shear function cuts presses the area to be located lower part generally beam, but as a result of the earthquake mutual action, the breast concrete protector possibly already flaked, thus weakened the concrete to cut presses the area anti to cut the ability。 Alternately slanting crack width ratio non earthquake resistance situation big, as well as the slanting crack make and break, the concrete is repeatedly more serious, thus causes in the slanting crack contact surface the aggregate linking effect degeneration。 Concrete protector flaking and the crack widen can enable the vertical muscle the cotter function to have the certain degeneration. Obviously, under the earthquake function, the concrete anti cuts the ability serious degeneration, but the experimental discovery stirrup anti cut the ability still to be possible to maintain.When the earthquake function more and more hour, the beam end possibly does not appear the double syncline crack, but appears the single syncline crack, the crack opening growth also from is bigger than the non earthquake resistance situation to approach the non earthquake resistance situation, anti cuts the environment to be more and more advantageous. In addition, resists earthquakes anti cuts the request structural unit to be supposed under the big quake to estimate achieved in front of inelasticity strained condition does not have the shearing failure. Because the frame shearing failure always occurs in the beam end plastic hinge area, this not only requests in the beam end to form in front of the plastic hinge not to have the shearing failure, moreover anti cuts the ability also to have to maintain to the plastic hinge plastic rotation achieved the big quake requests degree, this need more stirrups. At the same time, affects the shearing force in the beam end plastic deformation process not obviously to increase, also further explained here increases the stirrup is not uses for to increase the shearing strength, the ductility which but is for enhance the ponent when to have shearing failure reaches.In summary, with must resists earthquakes anti cuts pares, resists earthquakes anti cuts the performance is different, its performance and the shearing force function environment, the plastic area ductility request size concerns. Below we may adopt the formula to consider resists earthquakes anti cuts the intensity formula.Anti cuts the ability for the concrete, anti cuts the ability for the stirrup, for because the earthquake function causes the concrete anti cuts the reduction coefficient which the ability drops, also along with the shearing force function environment, the ductility request but changes. Our country39。s earthquake resistance shearing strength formula also take above formula as foundation, but for the design convenient, the different intensity area has used the same formula, takes is , mentions the concrete with the above anti to cut the ability but the different rule not to be inconsistent along with the earthquake function change, is sketchy.The ductility to resists earthquakes said is an extremely important nature, we must want to guarantee the structure through the earthquake resistance measure the ductility, then must clearly affect the ductility factor. Regarding ponent and so on beam column, the ductility influence factor finally may induce into the most basic two points: Concrete limit pressure strain, time destruction pression zone altitude. The influence ductility other factors essence all is these two basic factors extending. Like is pulled the steel bar ratio of reinforcement in a big way, concrete pression zone highly bigger, the ductility is worse。 Compression steel more, the concrete pression zone high goes past slightly, the ductility is better。 The concrete goes past high, the pression zone high goes past lowly, ductility better (but if conc