PS材料加固西北干旱区土遗址试验研究

土遗址是大遗址中最难保护的一类,而防风化加固是其中的难点,也是目前国际上普遍关注和攻关的课题,PS材料用于西北干旱区土遗址的防风化加固已获得了初步的成功.室内单轴抗压强度、抗剪强度研究发现,强度提高幅度满足要求,材料具有可重复使用性;通过对PS材料加固土遗址的微观结构特征进行研究,加固后X衍射图谱中部分矿物衍射强度降低和密集低矮的非晶体物相峰群的出现,定性说明,非晶质物相的生成加强了矿物间胶结作用;加固前后的红外谱图基本吻合,没有新晶质物相出现,仅是化学健间结合力略有提高;SEM图像显示骨架颗粒胶结状态由点状接触向胶结接触转变.研究表明PS材料与土作用后加强了土骨架颗粒的连结强度,而土的结构基本保持不变,宏观上改善了遗址土的水稳定性,增强了工程力学性能,满足文物保护的特殊要求.图10,表2,参13.

Study on the Soil Micromechanics of Consolidating the Earth Site Using PS Material in the Arid Region of Northwest China

The earth site is most difficult to protect in the Site.protecting the earth sites from weathering is the international difficult point and had caused wide attention.The PS material was applied to consolidating the earth site in the Northwest arid region and was succeeded in use.Through the compression test and the shear strength test,the results indicate that the compression strength and the shear strength are increased with the PS material consistency and the reinforcement times,and that the PS meterial can be multiple application.By adopting many multi-disciplinary techniques such as the X-ray,the IR,the SEM and the BET technique,studied the soil micromechanics which was consolidated by the PS material.In the X-ray spectrogram,some mineral diffract intensity of consolidated soil depressed,and there appear dense diffraction peak of uncrystalline phase.Above phenomena show cementation is increased and the structure becomes more stable.The infrared spectrum indicated that no new crystalline phase is produced and just the chemical bond increased a little.The SEM photo show the consolidated soil cementation changed from schistose cementation to silicic acid cementation.The outcome indicated that the connection between particles consolidated by PS was apparently strong and the soil structure doesn't change and will become more stable.On the whole,the engineering performance of the soil consolidated by the PS improved.10figs.,2tabs.,13refs.