The main girders of the Yuyao-Cixi Expressway Viaduct are the heavy load and sep-arated twin asymmetric precast prestressed concrete(PC)box girders.For the delivery and erec-tion of the box girders of the viaduct,the scheme of the eccentric delivery of a girder using a 850 t girder carrier to travel on the tops of the inner webs of the erected left and right box girders was a-dopted.To check the feasibility of the scheme,the eccentric static load bending test for the 1:1 model of a 32.5-m span and 733-t asymmetric precast PC box girder was made.The matching reac-tion frame for the test was designed,the load cases of the delivery of the girder on the real box girders were measured at the same time and the results of the measurement and test were compara-tively analyzed.T he results yield that in the eccentric static load bending test,the tested girder has been in the elastic deformation range all the time and the stress,displacement and crack resist-ance conditions of the girder can all meet the requirements.In the delivery of the girder on the real box girders,the force conditions of the box girders are all in the allow able range as specified in the codes,showing that the scheme of the delivery of the girder is safe and reliable.The test results and the longitudinal stress change values and change tendencies of the box girders in the delivery of the girder are in good agreement and both of them are characterized by the notable eccentric load effects.%余慈高速公路高架桥采用大吨位、非对称分幅预制预应力混凝土箱梁,预制箱梁运架过程中采用1台850 t级运梁车跨左、右幅已架箱梁内侧腹板顶面偏心运梁的方案.为验证该运梁方案的可行性,针对32.5 m、733 t的非对称预制箱梁的1:1模型开展偏心静载弯曲试验,并配套设计了偏心静载弯曲试验反力架,对实际梁上运梁工况进行测试,将实测结果与静载弯曲试验结果进行对比分析.结果表明:试验箱梁在偏心静载试验过程中一直处于弹性变形范围内,其应力、位移及抗裂情况均满足要求;实际梁上运梁过程中,箱梁的受力均在规范允许范围内,表明该运梁方案安全可靠;静载试验与实际运梁时箱梁纵向应力变化值及变化趋势吻合较好,均有较明显的偏载效应.
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