Interlaminar shear resistant strength testing method

The invention discloses an interlaminar shear resistant strength testing method which comprises the following steps: (1) shearing a composite material pipe into a plurality of test samples with same lengths along an axial direction, and respectively detecting the test samples and the rest pipe through a clamp detection mechanism and a releasing tool; (2) respectively testing the plurality of test samples sheared through a clamp testing mechanism, determining a minimum value of maximum pressure values of the plurality of test samples as the interlaminar shear resistant strength value F1, testing to obtain the shearing failure load F2 of a releasing connector through the releasing tool, calculating the interlaminar shear resistant strength value tau1 of the test samples by adopting a formula, and calculating the shearing failure strength tau2 of the releasing connector by adopting a formula; (3) calculating the corresponding relation coefficient alpha by adopting a formula; and (4) increasing the safety coefficient beta aiming at a downhole tool made from different composite materials, and acquiring pumping pressure P, namely the interlaminar shear resistant strength value, during the interlaminar failure of the downhole tool by adopting a formula. The interlaminar shear resistant strength testing method disclosed by the invention can be used for reducing the well completion construction failure caused due to insufficient interlaminar shear resistant strength of the composite material pipe.