PS加固土遗址土体的红外热像检测试验研究

红外热像技术作为一门新兴的无损检测技术,是基于被测对象温度场的变化规律而进行的,目前广泛应用于检测物体表面的结构状态、性质和内部缺陷等。为了探讨土遗址加固土体的无损检测方法,以新疆交河故城遗址现场采取的扰动土制作了模型。模型的1/2用浓度为10%PS(PS为一种高模数的硅酸钾溶液)加固,1/2不加固,将加固后的模型室温静置30 d,自然风干后进行了红外热像室内模型试验。试验表明,PS阻碍了土体的热传导过程,加固前后的土遗址土体在红外热像上会出现差异,为进行土遗址加固效果的无损检测提供了一种途径。最后进行了PS加固遗址土体的热传导率测定试验和微型贯入仪现场试验,结果表明加固土体与未加固土体的热传导性能产生差异的原因与经PS加固减小了土体的热传导率、提高了土体的力学强度有关。

Experimental study of infrared imaging technology detecting earthen ruins soil reinforced by potassium silicate(PS)

As a new type of newly arisen nondestructive testing technology, the conduction of infrared imaging technique is based on changes of the objects’ temperature field, which is widely used in the detection of objects’ structure state, properties, internal defects, etc. at present. In order to explore nondestructive testing method for potassium silicate(PS) reinforced earthen ruins soil, adopting the disturbed soil collected from site of Jiaohe Ruins to make soil models, halves of which are reinforced by 10% PS; and the others are untreated. And to keep the PS reinforced soil models standing for 30 d under the condition of room temperature until being naturally air-dried. And then, a laboratory model test detecting the reinforcement effect of PS through infrared imaging is conducted. It is shown that the PS hinders the heat transfer process of soil; besides, there is difference in the infrared thermal images for the PS reinforced soil and the PS untreated soil, which provides a possible method to carry out the non-destructive inspection of the reinforcement effect for earthen ruins soil. Finally, field test that micro-penetrometer detected the PS reinforcement effect and the determination test of the thermal conductivity are conducted; and the test results show that the reason for the difference in the heat conduction performance of the reinforced soil and the untreated soil is that PS reinforcement decreases the thermal conductivity and enhances the mechanical strength of earthen ruins soil