求翻译：4面层踢脚空鼓：面层空鼓主要原因是基层清理不净，浇水不透，早期脱水所致；另一个原因是上人过早，粘结砂浆未达到强度受到外力振动，将块材与粘结层脱离成空鼓，解决办法是加强清理及施工前基层的检查，注意控制上人施工的时间，加强养护，踢脚空鼓的原因是墙面基层清理不净，是什么意思？

4 surface layer kicked feet empty drum: surface layer empty drum main causes is grassroots cleanup not net, watering not through, early dehydration caused by; another causes is people prematurely, bond mortar not reached strength was forces vibration, will block material and bond layer detachment into empty drum, solution approach is strengthening cleanup and the construction Qian grassroots of check, note control people construction of time, strengthening conservation, kicked feet empty drum of causes is wall surface grassroots cleanup not net,