前言在工程实践中,经常会遇到一种具有特殊变形性质的粘性土,它的体积随含水量增加而膨胀,随含水量减少而收缩。具有这种膨胀和收缩特性的土,一般称之为膨胀土。当利用这种土作为房屋和构筑物的地基时,如果在工程地质勘察过程中,忽视了对它的胀缩性的注意和研究,或在设计和施工时没有采取必须的相应措施,把这种特殊的地基土误认为一般的粘性土来对待,结果会给建筑物造成危害。尤其对于低层轻型的房屋和构筑物带来的危害更大。反之,如果掌握和控制了它的胀缩特性,并采取了适当的设计 Foreword In engineering practice, there is often encountered a kind of cohesive soil with special deformation properties, its volume expands with the increase of water content, and shrinks with the decrease of water content. Soils with this kind of expansion and contraction characteristics are generally called expansive soils. When such soil is used as the foundation of houses and structures, if during the engineering geological survey, the attention and research on its deflation is neglected, or the necessary corresponding measures are not taken during design and construction, put this Special ground soils are mistaken for general clay soils, which can cause damage to buildings. Especially for lower-level light houses and structures, the harm is even greater. On the other hand, if you grasp and control its expansion and contraction characteristics, and take the appropriate design