矿渣与水泥固化广州南沙软土试验研究

EXPERIMENTAL STUDY OF NANSHA SOFT SOIL IN GUANGZHOU REINFORCED BY SLAG AND CEMENT

利用矿渣与水泥混合固化剂对广州南沙软土进行固化处理。通过直剪试验、无侧限抗压试验对固化土样进行了力学性能研究,得出固化土体的内摩擦角、黏聚力、无侧限抗压强度随固化剂中矿渣掺入比及龄期的变化关系。通过电子显微镜观测和X射线衍射技术研究不同配比下固化土样的矿物组成及微观结构特征。研究结果表明:固化土的内摩擦角、黏聚力和无侧限抗压强度均随矿渣占固化剂比例的增大而增大,其中黏聚力增长最明显;混合固化剂的最优配比为矿渣占固化剂比例为60%;矿渣占固化剂比例越高,固化土的后期强度增长越快。这与加固土体的微观结构和矿物组成成分中的水化产物有关。

In this paper, soft soil reinforced by slag and cement in Nansha （ Guangzhou） was studied.Through conventional soil test including direct shear test and unconfined compression test, reinforced soil ’ s mechanical property was researched and the correlation among its internal friction angle（ IFA） , cohesion, unconfined compressive strength（ UCS） and mix ratio or curing age were studied.Scanning electron microscope observation（ SEM） and X-ray diffraction technique（ XRD） were used to study different microstructure characteristics and the mineral composition of different reinforced soil samples.The results showed that the IFA, cohesion and UCS of reinforced soil were raised increasing with the ratio of slag in curing agent, and cohesion was increased most obviously.The optimum was application of 60%slag, and the higher the ratio of slag be adopted, the faster the later strength of reinforced cement soil was raised.All of that were related to the microstructure and hydration products of reinforced soil.