The　load　transfer　mechanism　and　failure　mode　of　narrow　soils　induced　by　rotating　about　the　top　of　excavation　retaining　structures　(RT　displacement　mode)　are　investigated　using　the　Finite　Element　Limit　Analysis　(FELA)　method　with　the　Hardening　Mohr-Coulomb　(HMC)　model.　A　logarithmic　spiral　curve　model　is　innovatively　proposed　to　accurately　characterize　the　evolution　of　the　failure　surface　in　narrow　soils　behind　retaining　structures　under　RT　displacement　mode　based　on　numerical　simulation　results.　Through　analysis　of　principal　stress　vector　diagrams　obtained　from　FELA　simulations,　an　asymmetric　soil　arching　effect　is　identified　in　the　upper　zone　of　the　narrow　soils　behind　the　retaining　structure.　An　optimized　differential　element　method　is　developed　by　constructing　asymmetric　arched　differential　elements　along　the　deflection　of　principal　stresses　at　the　soil＇s　limit　state,　thereby　establishing　an　analytical　framework　for　calculating　earth　pressure　in　narrow　soils　under　RT　displacement　mode.　The　proposed　analytical　method　is　validated　through　favorable　agreement　with　finite　element　analysis　results.　Additionally,　sensitivity　analyses　are　performed　to　evaluate　the　effects　of　soil　strength　parameters,　interface　friction　angles,　and　aspect　ratios　on　earth　pressure　distribution,　earth　pressure　coefficients,　and　the　location　of　the　resultant　thrust.