【摘要】 因综合交通枢纽建设需要,深圳市彩田立交桥被要求拆除。经多种拆桥方案比选,本文对该桥提出了“SMPT(self-propelled modular transporter)技术+大节段切割”的拆除方案。为确保拆除安全,本文采用有限元方法模拟主梁拆除全过程,同时现场布置测点,对拆除各工况下主梁变形进行实时监测。结果表明:预应力混凝土旧桥拆除时,应考虑其长期预应力损失影响;根据本文计算结果,彩田桥长期预应力损失按25%比例取值是合适的;各工况主梁变形计算值与实测值吻合良好,误差基本在10%以内,最大不超过14.7%。全桥拆除总计28h完成,现场噪音小,污染少,最大限度避免了对日常交通的影响,证明所提出的“SPMT技术+大节段切割”方案安全、高效、环境友好,实现了该桥绿色、环保、快速拆除的目的。更多还原

【Abstract】 Due to the need for comprehensive transportation hub construction, the CaiTian Overpass Bridge in Shenzhen was required to be demolished. After comparing various schemes, a demolish scheme of “SMPT(Self-propelled modular transporter) technology+large segment cutting” is proposed in this paper. To ensure structural safety during demolition, the finite element method was used to simulate the entire demolishing process and measuring points were set up to monitor the deformation of the main girder in real time under various demolition conditions. The results indicate that the long-term loss of prestressed concrete should be considered when demolishing old bridges, and the suggested 25% proportional value for the long-term loss of the prestressed force in the Caitian Bridge is appropriate, which is determined through comparing the calculated results from various formulas. The values of the calculated and measured deformations of the main girder under different working conditions are in good agreement, with errors mostly within 10% and a maximum of no more than 14.7%. The demolition of the entire bridge was completed in a total of 28 hours with little noise and pollution on site, and minimal impact on daily traffic was avoided, proving that the proposed “SMPT technology+large segment cutting” scheme is safe, efficient, and achieves the goal of green, environmentally friendly, and rapid demolition of the bridge.更多还原