Dynamicresponse Of Zhengyangmen Ancient Architectures Inducedby The Vibration Of Subway And Ground Traffic

ABSTRACT:With the development oftransportation construction, the ancient architectures, which are old and fragile though the rise and fall of dynasties, will be worse under the effect of environmental vibration, especially the traffic vibration. Therefore, government, scientists and researchers all around the world have paid more attention on the dynamic research of ancient architectures caused by environmental vibration, because of the importance of ancient architecture protection. The theoretical research achievements and in-situvibration test of ancient architectures are used for future protection, repairing and regular development of ancient architectures.Zhengyangmen gate tower and arrow tower in Beijing are chosen to be theresearch object, and the dynamic response of Zhengyangmenancient architectures caused by traffic vibration including vehicles vibration and subway vibration is studied.First, the traffic investigation of Zhengyangmen area is important, and based on the investigation, the traffic characteristicsof different types of vehicles on different routes can be calculated. The traffic characteristics include vehicle densitandinterval of adjacent car, and then the different type of vehicle vibration source on the road can be sumrized.Second,based on traffic investigationthe vibration characteristics of different vehicles can be sumrized and theoscillation equation of vehicles can be calculated though the vehicle dynamic model. According to the traffic characteristics, expression of each route also can be concluded. Because of the traffic light, the vehicles on the road move regularly. The traffic vibration propagates along the surface ground and reaches the bottom of the Zhengyangmen ancient architectures. The subway vibration characteristic is on the current research results, the location of metro line2, and the soil characteristic of Zhengyangmen area. The vibration field of surface traffic and subway can be used for the research of the vibration response of gate tower and arrow tower.Third, the vibration field of vehicles and subway is set based on the differenc of the two kindsvibration and the position of vehicels and subway.The vibration field is used for the dynamic research of gate tower and arrow tower.Fourth, the model of ancient architectures (gate tower and arrow tower)-surface traffic-subway tunnel is set for the dynamic analysis of gate tower and arrow tower induced by different types of traffic source. Thought data-analyzing, the vibration rules of gate tower and arrow tower can be summarized:(1) under the effect of traffic vibration, the vibration displacement and velocity of gate tower and arrow tower increacewith height;(2)the vibration displacement maximum value of gate tower is0.32mm, the vibration velocity maximum value of gate tower is4.5mm/s, the vibration displacement maximum value of arrow tower is0.28mm, the vibration velocity maximum value of arrow tower is3.8mm/s;(3)under the vehicle and subway vibration, when the vibration frequency of ancient architecturesis among the range1.7-2.3Hz, the value of the vibration velocity reaches the maximum;(4)the different types of vehicles vibration have different effect on the gate tower and arrow tower because of the different vibration characteristics of the vehicles, and also the different density of vehicles, the larger the density is the greater the effect is.The vibration characteristics of ancient architectures sumrized by theoretical calculated data are same as the in-situvibration test data, so the research method of traffic vibration in this paper is reasonably practicable, and can provide reference for dynamic research of similar structure ancient architectures.