Parameter maps where either silicate grains’ runaway pile-ups (labeled “RPU” in red color), icy pebble runaway pile-ups (labeled “RPU” in blue color) or steady state without runaway pile-ups (labeled “S” in black color) occurs for different α_tur and F_p/g (α_acc = 10⁻²). If the midplane dust-to-gas ratio of silicate grains is larger than unity for the case of “S”, the label is highlighted in red color. If the midplane dust-to-gas ratios of pebbles as well as those of silicate grains are larger than unity for the case of “S”, the label is highlighted in blue color. Left, middle and right panels: cases of K = 0, K = 1 and K = 2, respectively.