慢裂型水泥稳定碎石基层材料的设计方法

在传统的、以强度为设计指标的基础上,提出了水泥稳定碎石的新设计指标——抗裂指数,并认识到在进行混合料组成配合比设计时,在满足强度要求的前提下,如能控制抗裂指数接近于或小于1,则能明显提高水泥稳定碎石混合料的缓裂或抗裂性能,从而设计出缓裂型的水泥稳定碎石。在室内试验研究的基础上,通过试验路的铺筑,提出原材料及其用量控制:在苏南及水环境、温度条件类似的地区宜控制水泥用量小于等于5%;宜控制集料中4.75mm筛的通过量在29%～39%之间。

Design Method of Slow Cracking Cement-stabilized Aggregates

Based on the traditional strength index used in design,a new design index-anti-cracking index was brought forward for the design of cement-stabilized aggregate.If strengths were sufficient and furthermore anti-cracking indexes were close to or less than 1,the performances of cement-stabilized aggregates in slowing or resisting crack growth would be improved obviously,when the mixture ratio of cement-stabilized aggregate materials was designed.Therefore,a kind of cement-stabilized aggregate to delay the cracking could be designed.Based on the test and research in laboratory,the field test road was constructed,and accordingly it brought forward the controlling of original materials and their dosages: In the South of Jiangsu Province and areas with the similar water environment and temperature condition,the cement dosage of the cement-stabilized aggregate ought to be controlled at 5% or less and the percentage passing through 4.75 mm's sieve of aggregate gradations ought to be controlled over 29%~39%.