【摘要】 水泥稳定砂砾在多年冻土地区路面基层应用中普遍出现了板体性差、强度低等问题,通过模拟多年冻土地区实际温度变化和单一恒温的强度试验,与标准养生条件对比分析了特殊温度条件对水泥稳定砂砾混合料强度形成的影响。研究得出,多年冻土地区特殊的低温和负温条件将明显延缓混合料强度的形成速度;养生温度对混合料强度形成的影响存在临界状态,当第二天养生温度达到研究得出的临界温度分界点7℃后,只通过提高养生温度来进一步提高强度或加快强度增长的效果并不明显。结果表明,多年冻土地区特殊的温度条件是基层出现板体性差和强度低等问题的主要原因,解决问题的关键在于采取提高混合料设计强度、掺入外加剂、保温和封闭施工等技术措施,保证和提高早期强度,降低负温和低温影响程度。更多还原

【Abstract】 Some problems, for example unformed harden or low strength, appear widely in the cement stabilized gravel base in permafrost areas. By strength test simulating the actual temperature of permafrost area and the single constant temperature, the influence of the special temperature on strength formed in cement stabilized gravel are contrastively analyzed with the standard conditions. It is pointed that low temperature and minus temperature of permafrost areas evidently retard the strength forming speed of the cement stabilized gravel mixture. There is a critical effect state of curing temperature on the mixture strength formed. When the temperature of the second day has reached 7 ℃, to increase curing temperature only has no evident effect on advancing mixture strength or fasting strength formed. The results indicate that the special temperature of the permafrost areas is the main cause of the base problems. The key to solving the problems is to assure and improve the early strength of the mixture to reduce the influence of low temperature and minus temperature by taking some technical measures, such as increasing design strength, mixing into the addition agents, preserving temperature or closing construct and so on.更多还原