Imrul, who played a match-winning knock of 144 runs in Sunday’s series opener, shared 148 runs with Liton Das in the opening stand, Bangladesh’s best ODI start in 2018.
Liton chipped in with 83 off 77 balls after being reprieved on naught by the third umpire, who overturned a leg-before decision in the very first over of the innings following a television replay.
Off-break bowler Sikandar Raza dismissed Liton to break the stand and then also had number three Fazle Mahmud in his next over, but Imrul stood firm to deny Zimbabwe further momentum.
Raza also removed Imrul, who hit only seven fours in his 111-ball innings, before finishing with 3-43.
Bangladesh skipper Mashrafe Mortaza acknowledged dew in the field made their job easier.
“I think winning the toss was crucial. We knew about the dew, but it was not as much as we expected,” Mortaza said.
Mushfiqur Rahim and Mohammad Mithun were unbeaten on 40 and 24 runs respectively.
Mithun clinched Bangladesh’s 12th successive win over Zimbabwe in style, hitting left-arm spinner Cephas Zhuwao for a six over deep square leg.
Sent into bat first, Zimbabwe earlier lost skipper Hamilton Masakadza (14) quickly but Brendan Taylor hit 75 off 73 balls while Raza (49) and Sean Williams (47) played two useful knocks to give them a competitive score.
Taylor added 52 and 77 runs for the second and third wicket respectively with Zhuwao (20) and Williams before Bangladesh stalled Zimbabwe’s progress.
Taylor, who hit nine fours and a six in his eighth fifty against Bangladesh, the highest by any cricketer, also benefited from a television replay as he was reprieved on 42 after being given out leg before wicket initially.
Zimbabwe’s Masakadza lamented their inability to capitalise on a good start.
“We didn’t manage to kick on after the kind of start. Credit to Bangladeshi bowlers for starving us at the death,” he said.
Rookie all-rounder Mohammad Saifuddin finished with the most impressive figures of 3-45 for the home side and was named man of the match.
The third and final match of the series will also be held at the same ground on Friday.