二灰钢渣碎石路面基层材的设计与使用性能

Design and Performance of Lime and Fly-ash Stabilized Steel-slag and Crushed-stone Pavement Base Materials

通过实验室试验,研究了路面基层用石灰粉煤灰稳定钢渣碎石集料混合料的使用性能.试验结果及分析显示:二灰稳定钢渣碎石混合料无侧限抗压强度随钢渣质量分数增加而显著增加,掺钢渣可以减少二灰结合料的用量.钢渣碎石合成集料遇水累计膨胀率可以通过改变钢渣的掺量控制,必须在材料设计时予以考虑.钢渣可以提高二灰稳定材料间接抗拉强度与抗压回弹模量,集料中掺50%钢渣可以分别提高材料的抗拉强度与抗压回弹模量最高24%与21%,减小设计路面结构层厚度.钢渣可以减小二灰稳定材料总干缩系数,集料中掺50%钢渣可以减小材料的干缩系数最多27%,减缓路面基层由于失水导致的开裂.钢渣的存在对二灰稳定材料抗冲刷特性影响不大,材料设计时可以不必考虑.

Laboratory tests were carried out to investigate the performance of lime and fly-ash inorganic binder stabilized steel-slag and crushed-stone aggregate mixtures for pavement base. The test results and analyses indicate that the unconfined compressive strengths of the mixtures increase significantly with the increase of slag content. In other words, the slag can reduce the use of the inorganic binder. The moisture induced expansion rate of combined aggregate can be controlled by changing steel-slag content, which must be considered in the material design. The slag can increase the indirect tensile strengths and compressive moduli of the mixtures. A content of 50% slag in the aggregate can increase the strength and modulus by up to 24~ and 21~, respectively, resulting in layer thickness reduction in the designed pavement struc- ture. The slag can decrease the dry-shrinking coefficient of the mixtures. A content of 50% slag in the ag- gregate can decrease the coefficient by up to 270/6, resulting in moisture loss induced cracking alleviation in pavement base. The existence of slag has little effect on the water scouring properties of the mixtures, which does not have to be considered in the material design.