  Two-particle two-hole (2p2h) effect on the Gamow-Teller (GT) transition for
neutron-rich nuclei is studied by the second Tamm-Dancoff approximation (STDA)
with the Skyrme interaction. Unstable $^{24}$O and $^{34}$Si, and stable
$^{48}$Ca nuclei are chosen to study the quenching and fragmentation of the GT
strengths. Correlation of the 2p2h configurations causes $20$\% quenching and
downward shift of GT giant resonances (GTGRs). The residual interaction
changing relative angular momentum, appeared in the tensor force part, gives a
meaningful effect to the GT strength distributions. In this work, $17$ to $26$
\% of the total GT strengths are brought to high energy region above GTGRs. In
particular, the tensor force brings strengths to high energy more than $50$
MeV. STDA calculation within a small model space for 2p2h configuration is also
performed and experimental data of $^{48}$Ca is reproduced reasonably.
