Because the best grade limits does not vary with material property , firstly , we can confine material grade to the best grade limits when doing subbase mixture design , secondly , after systematic temperature contraction test , aridity contraction test and compressive strength correction test , we can determine the best cement percentage which has the best crack resistance property 因為最佳級配范圍是與粒料的粒徑大小有關(guān)的,所以在基層材料配合比設(shè)計時可首先將材料級配限制在最佳級配范圍以內(nèi),然后通過系統(tǒng)的溫縮、干縮性能試驗以及抗壓強度校核試驗,最終確定抗裂性較好的合理水泥劑量。