Study On The Design Of Building Wall Protection Structure And Anti-explosive Impact Performance

For the issues of engineering protection,this thesis studies the protection of building walls under explosive loads.UHMWPE is used as the basic material,and this thesis designs a protective board structure based on this material,and discussed the anti-blast and antipenetration performance of this lightweight fiber material protection board and its protective effect on the wall.The study method mainly uses numerical simulation,designed and built a UHMWPE protective board model,and make it externally protect the general building wall under explosive load.Through the finite element calculation,the damage and dynamic response of the protective board and the wall are analyzed,and the damage mode of the protective board and the wall is obtained.Afterwards,through the parametric analysis method,the protective effect of the protective board under the single shock wave action and the combined action of shock wave fragments was quantitatively analyzed.And from the two aspects of structure and material,the UHMWPE protective board has been optimized.The specific content is as follows:(1)This article first determines the constitutive model of the materials involved,then use LS-DYNA to simulate the explosion and penetration based on the fluid-structure coupling algorithm;The accuracy and validity of this calculation method and the selected material model were verified respectively,and follow-up studies were carried out on this basis.(2)Designed a new type of UHMWPE cavity protection board,and by setting different burst distances and equivalents,the protective effect of this protective board and the response of the wall were simulated and analyzed,and set up a control group without protective boards.It can be concluded that under the action of a single shock wave,the cavity board has a significant effect on the attenuation of the peak overpressure;From the perspective of energy absorption,appropriately increasing the thickness of the front and rear boards of the protective board can effectively reduce the internal energy of the wall;From the perspective of the wall,the cavity protection board can effectively reduce the maximum displacement behind the wall.In addition,through a summary analysis of the proportional blasting distance and wall damage of different working conditions,it can be obtained that under the protection of the protective board in this article,the safe proportional blasting distance of the general C30 wall without damage.Finally,optimized the structure of the cavity protection board.Ribbed equidistantly in the cavity of the protective board,And under the same explosion conditions and the original cavity board for comparative analysis.(3)On the basis of the previous modeling analysis,a parametric analysis of the protective board and wall under the combined action of explosion shock wave and fragment penetration is carried out,and the penetration damage form of the protective board and the wall is obtained.Then made two comparisons,one set is a cavity board and a solid board with the same areal density.Through this group,the cavity board has better performance at attenuating shock wave overpressure,but the overall deformation is larger,and the solid board attenuates the fragment velocity.The performance has been improved to a certain extent,but the pressure relief performance is not as good as the cavity plate.By comparison,it is concluded that the design of the protective board into a cavity form is more conducive to explosion-proof;The other group adds the metal material aluminum,the UHMWPE protective board has been optimized in terms of materials.First,the same quality aluminum board and UHMWPE board are simulated under the same explosion conditions,then the two materials are laminated and continue to calculate and analyze.It has been obtained that using aluminum board as the upper and lower layers and UHMWPE board as the sandwich layer can effectively improve the impact resistance and penetration resistance of the protective board,and can greatly reduce the overall deformation of the protective board.