水泥土物理力学性质试验研究Water soil physical and mechanical properties of the experimental research摘要：基于山东省济菏高速公路软基加固试验资料的分析，探讨了水泥土的物理力学性能及其变化规律。
结果表明，影响水泥土抗压强度的主要因素有水泥掺量、龄期和含水率，水泥土抗压强度随水泥掺量的增大而增大，两者呈幂函数关系，随龄期的增长而增大，随土样含水率的增加而迅速降低。
其应力-应变关系呈非线性关系，表现为弹塑性材料的性质。
另外水泥土的压缩系数随水泥掺量的增加而减小，变形模量、抗拉强度和抗剪强度都随抗压强度的增大而增大。
关键词：水泥土；强度；变形；水泥掺量；龄期；含水率Abstract: based on the shandong province He highway has soft foundation reinforcement test data analysis, probes into the soil water of physical and mechanical performance and the changing laws. The results showed that soil water influence the compressive strength of cement content is the main factors, and moisture content of cement, water the compressive strength of the cement soil with the mixed quantity increases, both a power function relation between, along with the growth of the age increases with the increase of the moisture content of the soil sample lowers quickly. The nonlinear stress-strain relationship, for the performance of the elastic-plastic material properties. In addition of cement-treated soil cement mixed quantity compression coefficient with the increase and decrease, elastic modulus, tensile strength and shear strength as the compressive strength increases.Keywords: water soil; Strength; Deformation; Cement mixed quantity; ); Moisture content1引言济菏高速公路地处黄河下游东部黄泛冲积平原，沿线为第四纪覆盖区，出露地层主要为第四纪粉土、粘性土、砂土等，厚度150m-400m。
根据野外地质钻探及室内土工试验等勘察资料综合分析，部分路段属于软土地基需进行加固处理，经多方案比较，决定采用水泥土搅拌法。
水泥土搅拌法是加固软弱地基的一种新型技术，是以水泥作为固化剂，通过特制的深层搅拌机械，在地基深处就地将软土和水泥强制搅拌，利用水泥和软土之间所产生的一系列物理化学反应，使软土硬结成具有整体性、水稳定性和一定强度的优质地基［1］。
目前这项技术的发展仅经历三十年，无论从加固机理到设计计算方法或者施工工艺均存在有待完善的地方，有些还处于半理论半经验的状态，再加上施工的隐蔽性，因此对水泥土进行室内试验研究是保证地基加固效果的重要途径。
本文结合济菏高速公路工程水泥土搅拌法软基加固实例，通过室内试验，探讨水泥土的物理力学性能及其变化规律，为高速公路软土地基加固提供理论依据。
1、IntroductionJackie He highway is located in the lower Yellow River alluvial plain of the eastern yellow, for covering area along the quaternary, the open country layer mainly for quaternary powder soil, cohesive soil, sandy soil, thickness of 150 m-400 m. According to the field geological drilling and indoor substation survey data such as comprehensive analysis, the partial road section belong to the soft soil foundation reinforcement to, the more alternatives, decided to use of mixing method. Mixing method is the weak foundation reinforcement of a new technology, is the cement as curing agent, through the special deep mixing machine, in deep foundation shortcut to soft soil and the compulsory mixing cement, cement and use of soft soil generated between a series of physical and chemical reaction, make soft soil with integrity, hard to form water stability and a certain intensity of high quality foundation [1]. Now the technology development experience only thirty years, no matter from strengthening mechanism to the design calculation method of construction technology or there are to be the perfect place, some still at half the state of experience and a half theory, plus the concealment of the construction, so the water the indoor test research foundation reinforcement effect is to ensure that the important way. This paper has He highway engineering of mixing method of soft foundation reinforcement example, through the laboratory test, this paper discusses the physical and mechanical properties of soil water and its change rule, for highway soft foundation improvement to provide the theory basis.2原材料物理力学性质试验2.1原状土原状土取自济菏高速公路K133+000-K136+000路段2.2m以下，按《公路土工试验规程》［2］，土层主要物理力学指标见表1。
从表1可以看出，1、2、3、4土层含水率、孔隙比较大，承载力不大于100kPa，土质较差，当上部荷载较大时，必须进行加固处理。
2、physical and mechanical properties test raw materials2.1 undisturbed soilPrimary state soil has taken from He highway K133 + 000-K136 + 000 sections 2.2 m the following, by "highway soil test code" [2], soil mainly the physical and mechanical indexes see table 1. Can be seen from table 1, 1, 2, 3, 4 soil moisturecontent and pore is bigger, bearing capacity is not more than 100 kPa, soil is poorer, when the upper loads bigger when, the need for reinforcement.采用山东水泥厂生产的32.5普通硅酸盐水泥，物理力学指标见表2。
2.2 CementThe shandong cement plant production of 32.5 ordinary Portland cement, the physical and mechanical indexes in table 2.Table 2:32.5 the physical and mechanical properties of ordinary portland cement3水泥土物理力学性质试验试验按照《公路土工试验规程》和《公路工程无机结合料稳定材料试验规程》进行。
3.1重度由于拌入软土中水泥的重度与软土的重度相近，所以水泥土的重度与天然软土的重度也相近。
水泥土的重度试验结果见表3。
3 water soil physical and mechanical properties of testTest according to the highway soil test procedures "and" the highway engineering inorganic material with stable material experiment rules ".3.1 severeBecause mix in the soft soil in the severe and soft soil cement severe similar, so the soil water with severe natural soft soil near the severe also. The severe water soil test results to table 3.由表3可见，水泥土的重度与天然软土的重度相近，水泥掺量为20%，水泥土的重度仅比天然软土增加3%。