Partial lumped mass method in longitudinal deck-pier poundings of girder bridges and its test verification

Contact element methods have been widely used in the field of bridge poundings in recent years. For deck-pier poundings of girder bridges, two kinds of contact element methods are commonly used. One is the Lumped Parameter Method (LPM), which simplifies two pounding bodies to be two particles respectively, and the stress wave propagation phenomenon is disregarded. The other one is the Watanabe and Kawashima Method (WKM), whose weakness is that the pounding stiffness introduced to describe the pounding process is supposed and artificial. A new method, named as the Partial Lumped Mass Method (PLMM), was put forward for longitudinal deck-pier poundings of girder bridges and was introduced in this paper. Its applications were discussed in detail at first. Pounding force time histories with different Partial Lumped Factors were derived. The Rational Partial Lumped Factor was suggested theoretically. At last, the analysis results using the PLMM with different Partial Lumped Factors were compared, and the validity of the PLMM suggested in this paper was verified with shaking table test results.