作为公路桥梁的抗震措施，防落梁系统是针对落梁震害的减、抗震设计方法，由梁搁置长度、限位装置和连梁装置构成。连梁装置是结构遭遇超预期地震作用时，保证桥梁结构不发生落梁震害的最终安全保护措施，其防落梁效果受到各种设计参数的影响。结合国内外已有的连梁装置设计方法，对设置不同设计参数拉索式连梁装置的结构进行地震响应分析，研究设计参数对连梁装置防落梁效果及其内力的影响。结果表明，连梁装置的防落梁效果随着拉索长度、设计位移量的增大有所减小，但设计参数取值较小的连梁装置内力较大，部分超过连梁装置的设计承载力。

As an aseismatic measure of highway bridges, collapse-proof system is the method for seismic design and retrofitting, which consist of adequate seat length, seismic restrainers and unseating prevention devices. Unseating prevention devices are the ultimate security installment to prevent the girders form falling off the piers when bridge hit by earthquake, the effect of them are influenced by the design parameters. Based on the relational design standards at home and abroad, the seismic response of structures with different cable-unseating prevention devices, the pressure of unseating prevention devices and the effect of collapse-proof changed with cable length and design moving value were compared. The result show that the effect of collapse-proof decrease as the cable length and design moving value increase，the pressure of unseating prevention devices is larger than the design bearing capacity while the prarmeters are both smaller.