Study On The Safety Basis Of Reinforced Concrete Explosion-protection Wall

From the existing building codes and standards, building an explosion-proof wall with enough intensity is an important measure to relieve explosion accident harm to the workshop, storage, process unit which is in explosion danger. The set of explosion-proof wall takes on an important role to the safety production of factory, especially chemical industry. But toward explosion-proof wall, the maximal occasional explosion load that it can endure, arrangement of reinforcing steel bar, reasonable and effective building way and etc. are reported little at present. The detailed calculation step is little appeared on the correlative documents at home and abroad.Chemical explosion load is a dynamic load changed with time. The material will show completely different transformation feature under dynamic load and quasi-static load. Similarly, structure will show different destruction form under the effect of different load. So, the anti-detonation ability of the structure can be truly realized after understanding the response of that under the load.In this paper, based on the particular technology, some analytic techniques for the design of factory anti-explosion structure are provided. From the correlative data, the reinforced concrete structure is found not only with better anti-detonation capability but also economical. So, in this paper, the setup of the reinforced concrete explosion-protection wall is discussed principally. The main research work of this paper is as follows.(1) The basic structures of the explosion-protection wall of chemical industry are introduced simply. The advantage, significance of reinforced concrete finite element analysis and the research actuality of reinforced concrete structure dynamics response are introduced.(2) Based on the medium type of commercial production, the explosion accident and the destruction effect which possibility happened is forecasted. The relevant flow chart of disaster analysis and forecasting is established. The computational model ofthe destruction effect of the explosion mode forecasted is analyzed. The forecast and analysis is a qualitative analysis for the explosion fountainhead. And it is an important gist to the estimation of fountainhead explosion character and explosion energy calculation in the design of explosion- protection wall.(3) From the effect of shock wave to object, the overpressure-impulse criterion is elaborated. The protective schematic diagram of explosion-protection wall is given. The minimum safe distance concept and the confirming gist of the setup of the explosion-protection wall are put forward.(4) The reinforced concrete explosion-protection wall is designed by approximate design and numerical calculation method. Base on the mechanics of explosion, impact dynamics and construction mechanics, a reinforced concrete explosion-protection wall from actual structure is chose as the object for the calculation and simulation. Wall can be calculated as a unidirectional board. First, the source of the explosion is estimated and the explosion energy is calculated. Through referring the pertinent manual and standards, the shock wave load is simplified. The maximal dynamic load, dead load, the time of structural response and other parameters acted on the structure are calculated. Then the structure is designed and checked by selecting correlative parameter of material and structure. The design parameters of the explosion-protection wall which distance from the explosion source proper space and with adequate resistant can be get by the design and checking computation. The design parameters are the size of the wall, the structure strength, the bending moment, the ratio of reinforcing steel bar, the mask ant thickness and etc. Last, the author establishes the finite element model, test and verify the validity of numerical calculation after analysis.(5) The destruction process of the explosion-protection wall is simulated by using transient dynamics analysis of ANSYS. By using the advantage of the numerical analysis, the arrangement of the bar, the ratio of height to span, the thickness, the concrete grade, the pressure-time course of the load are changed to analyze the model. By the changing of the parameters and analysis, the transformation rule of the wallunder the explosion load can be got. The rule of the stress of the concrete and reinforcing steeling follows the time can be got at the same time. The anti-detonation capability of the explosion-protection wall under various behaviors is evaluated to find out the most important factor to the structure response. All these work offer the theoretical principle and meritorious reference data for the economical and reasonable building of the explosion-protection wall.(6) According to the design and analysis characteristic of the reinforced concrete explosion-protection wall, the user interface and the relevant analysis module of ANSYS are redevelop by using APDL and UIDL language. Quadratic development implement the analyze automation of the reinforced concrete explosion-protection wall.