爆破荷载作用下不同尺寸埋地钢管的动态响应实验研究

摘要

爆破荷载作用下埋地管道的动态响应是城市爆破施工中亟需解决的问题,具有重要的理论和现实意义.在理论分析的基础上,通过改变药量、爆心距对不同尺寸埋地无缝钢管进行了现场爆破实验.结果表明:在正常工作压力下钢管内径和管壁厚度的比值越大,当量应力和当量应变越大,同时管道容许压缩应变值随管道内径与管壁厚的比值的增大而减小.通过实测数据分析发现:在相同条件下,S1拉应变为S2拉应变的41％;S2拉应变为S3拉应变的40％;S1压应变为S2压应变的23％;S2压应变为S3压应变的58％.在爆破荷载作用下管道截面三迎爆面环向拉压应变均随着管道内径与管壁厚的比值的增大而增大.实验中S3最易被破坏,S2其次,S1次之.在满足工程需要的前提下可在铺设管道时选择相对管壁厚、内径小的管道,能有效增加抗振性能.%The dynamic response of buried pipelines under blasting load is an urgent problem to be solved in urban blasting construction,which has important theoretical and practical significance.Based on the theoretical analysis,the field blasting experiment was carried to the different sizes of buried seamless steel pipe by changing the dosage and the explosion center distance.The results show that under the normal working pressure,the larger the ratio of the inner diameter of the steel tube to the thickness of the tube wall,the greater the equivalent stress and equivalent strain,and the allowable compressive strain of the pipe decreases with the increase of the ratio of the inner diameter of the pipe to the wall thickness of the pipe.Through the analysis of the measured data,it is found that under the same conditions,the S1 tensile strain is 41％ of the S2 tensile strain;the S2 tensile strain is 40％ of the S3 tensile strain;the S1 compressive strain is 23％ of the S2 compressive strain;and the S2 compressive strain is 58％ of the S3 compressive strain.Under the action of blasting load,the circumferential compressive strain of the pipe cross section three is increased with the increase of the ratio of pipe diameter to pipe wall thickness.In this experiment,S3 is most likely to be destroyed,followed by S2,followed by S1.Under the premise of meeting the needs of the project,the pipeline with relatively small wall thickness and small inner diameter can be chosen to effectively increase the anti vibration performance.