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Filaments are ubiquitous structures in molecular clouds and play an importantrole in the mass assembly of stars. We present results of dynamical stabilityanalyses for filaments in the infrared dark cloud G14.225$-$0.506, where adelayed onset of massive star formation was reported in the two hubs at theconvergence of multiple filaments of parsec length. Full-synthesis imaging isperformed with the Atacama Large Millimeter/submillimeter Array (ALMA) to mapthe $\mathrm{N_2H^+} \; (1-0)$ emission in two hub-filament systems with aspatial resolution of $\sim 0.034 \; \mathrm{pc}$. Kinematics are derived fromsophisticated spectral fitting algorithm that accounts for line blending, largeoptical depth, and multiple velocity components. We identify five velocitycoherent filaments and derive their velocity gradients with principal componentanalysis. The mass accretion rates along the filaments are up to $10^{-4} \;\mathrm{M_\odot \, \mathrm{yr^{-1}}}$ and are significant enough to affect thehub dynamics within one free-fall time ($\sim 10^5 \; \mathrm{yr}$). The$\mathrm{N_2H^+}$ filaments are in equilibrium with virial parameter$\alpha_\mathrm{vir} \sim 1.2$. We compare $\alpha_\mathrm{vir}$ measured inthe $\mathrm{N_2H^+}$ filaments, $\mathrm{NH_3}$ filaments, $870 \;\mu\mathrm{m}$ dense clumps, and $3 \; \mathrm{mm}$ dense cores. The decreasingtrend in $\alpha_\mathrm{vir}$ with decreasing spatial scales persists,suggesting an increasingly important role of gravity at small scales.Meanwhile, $\alpha_\mathrm{vir}$ also decreases with decreasing non-thermalmotions. In combination with the absence of high-mass protostars and massivecores, our results are consistent with the global hierarchical collapsescenario.

Filamentary Accretion Flows in the Infrared Dark Cloud G14.225-0.506 Revealed by ALMA