A clamping plate dimensioned to secure an associated flexible spring member to an associated end member for forming an associated gas spring assembly (AS1; AS2), said clamping plate comprising: a clamping plate wall having a longitudinal axis and extending radially outward from along said longitudinal axis, said clamping plate wall including: a first end surface portion disposed along a first side of said clamping plate; a second end surface portion disposed along a second side of said clamping plate that is spaced longitudinally from said first side and facing opposite said first end surface portion; an outer peripheral surface portion extending between and operatively connecting said first and second end surface portions (404, 406), said outer peripheral surface portion at least partially defining an outermost cross-sectional dimension of said clamping plate and dimensioned to abuttingly engage the associated flexible spring member (200; 200') for urging at least the associated flexible spring member (200; 200') into a substantially fluid-tight seal with the associated end member for forming the associated gas spring assembly (AS1; AS2); a first opening extending into said clamping plate wall and being fluidically accessible from along said first end surface portion; a second opening extending into said clamping plate wall and being fluidically accessible from along said second end surface portion; and, a passage surface portion at least partially forming an elongated damping passage extending through said clamping plate wall, characterised in that said elongated damping passage extends in a spiral configuration disposed within a plane oriented transverse to said longitudinal axis and through said clamping plate wall in fluid communication between said first and second openings (418, 420) such that said elongated damping passage has an overall length substantially greater than said outermost cross-sectional dimension of said clamping plate. a clamping plate wall having a longitudinal axis and extending radially outward from along said longitudinal axis, said clamping plate wall including: a first end surface portion disposed along a first side of said clamping plate; a second end surface portion disposed along a second side of said clamping plate that is spaced longitudinally from said first side and facing opposite said first end surface portion; an outer peripheral surface portion extending between and operatively connecting said first and second end surface portions (404, 406), said outer peripheral surface portion at least partially defining an outermost cross-sectional dimension of said clamping plate and dimensioned to abuttingly engage the associated flexible spring member (200; 200') for urging at least the associated flexible spring member (200; 200') into a substantially fluid-tight seal with the associated end member for forming the associated gas spring assembly (AS1; AS2); a first opening extending into said clamping plate wall and being fluidically accessible from along said first end surface portion; a second opening extending into said clamping plate wall and being fluidically accessible from along said second end surface portion; and, a passage surface portion at least partially forming an elongated damping passage extending through said clamping plate wall, characterised in that said elongated damping passage extends in a spiral configuration disposed within a plane oriented transverse to said longitudinal axis and through said clamping plate wall in fluid communication between said first and second openings (418, 420) such that said elongated damping passage has an overall length substantially greater than said outermost cross-sectional dimension of said clamping plate. a first end surface portion disposed along a first side of said clamping plate; a second end surface portion disposed along a second side of said clamping plate that is spaced longitudinally from said first side and facing opposite said first end surface portion; an outer peripheral surface portion extending between and operatively connecting said first and second end surface portions (404, 406), said outer peripheral surface portion at least partially defining an outermost cross-sectional dimension of said clamping plate and dimensioned to abuttingly engage the associated flexible spring member (200; 200') for urging at least the associated flexible spring member (200; 200') into a substantially fluid-tight seal with the associated end member for forming the associated gas spring assembly (AS1; AS2); a first opening extending into said clamping plate wall and being fluidically accessible from along said first end surface portion; a second opening extending into said clamping plate wall and being fluidically accessible from along said second end surface portion; and, a passage surface portion at least partially forming an elongated damping passage extending through said clamping plate wall, characterised in that said elongated damping passage extends in a spiral configuration disposed within a plane oriented transverse to said longitudinal axis and through said clamping plate wall in fluid communication between said first and second openings (418, 420) such that said elongated damping passage has an overall length substantially greater than said outermost cross-sectional dimension of said clamping plate.