The invention discloses a bridge floor multi-axis
moving load recognition method based on the
diagonal relaxation orthogonal projection iterative
algorithm. The method includes the following steps that firstly, m displacement sensors are attached to corresponding positions x1, x2,..., xm on the bottom face of a bridge, and the displacement of a bridge floor multi-axis moving vehicle load fk(t) at the x position at the t moment is v(x,t), wherein k is 1,2,3,..., and k is the number of vehicle axles; secondly, an oscillatory
differential equation is established; thirdly, the equation (1) is solved; fourthly, a multi-axis
moving load system equation recognized by displacement responses is established for the bridge under the k-axis vehicle load action; fifthly, the precise value of a multi-axis
moving load is solved through the
diagonal relaxation orthogonal projection iterative
algorithm. The multi-axis moving load can be recognized by measuring the bridge displacement responses only, the recognition method is simple, precision is high, feasibility is good, and the method can be widely applied to moving load recognition of various types of bridges.