The elements affecting total settlement during vacuum preloading consolidation were discussed . the principle that defined the coefficient of total settlement correction by the magnitude of combined loadings was suggested . the mechanism and compone 分析了真空预压加固地基总沉降的组成，对各部分沉降计算做了分析，并建议按联合堆载量大小来总结真空预压加固地基沉降修正系数。
In recent years , vacuum preloading is extensively used to treat soft clay ground , whereas the development of the theoretic study in vacuum preloading cannot follow the progresses in engineering , which has limited the progress and application in engineering practice 目前有关真空预压加固地基的理论研究落后于工程实践，制约了该工法的进一步发展和工程应用，有必要对此进行系统的研究。
We can reduce settlement in two ways : one is to reduce the weight of the road embankments using lightweight filling . and the other is to improve the soil ground such as forming composite ground to enhance the bear weight of the ground and reduce the settlement 减小沉降可以从两个方面入手：一是减小路堤的荷载，即采用轻质路堤填料；二是加固地基即形成复合地基，通过提高地基的承载力来达到减小沉降的目的。
How many pumps were turned on should be based on the dynamic design according to project target . and how many pumps should be in operation in standard shut off procedure . it was approved that although the theoretical boundary of decline of groundwater level is 10m , the actual boundary is only about 6m 提出了一些与真空预压加固地基设计相关的概念和处理方法，如定义真空预压加固区场地形状系数，提出按加固土体体积来确定射流泵数量、根据工程需要动态设计开泵量、增加停泵标准中对开泵量的规定等设计思想等，论证了真空预压加固地基时地下水位下降的理论极限深度为10m ，而实际极限深度约为6m 。
Some key subjects of numeric analysis were discussed such as : selecting principles of constitutive equations of soft clay , the equivalent theory of vertical drains ground , the definition of load step , the determination of vertical drains as well as the treatment methods of the decline of groundwater level , sealing wall and nearby water source 着重论述了真空预压加固地基数值分析中对土体本构方程的选择、砂井地基等效转换、分析荷载步的确定、竖向排水体的界定、地下水下降的处理、密封帷幕的处理、附近补充水源的处理等问题。
In order to search after its applying to expressway roadbed improvement , this paper studied consolidation characteristic and distortion law hi soft soil under positive and negative action , introducing parse explain and numerical calculation theory . additionally , based on locale experimentation , the design and construction method of vhlcp was implemented and its reinforce effect and economical character was estimated . testing indicated that the groundwork ' s intensity have increased 97 % , silt soil have vanished and outlay have saved 39 % 根据现场试验，确定了适合于高速公路工程要求的真空堆载联合预压的设计和施工方法，并分析评价了其加固效果和经济性，试验表明：应用真空堆载联合预压后，地基强度平均提高了97 ，地基中淤泥质土已消失；与粉喷桩加固地基相比，节省经费39 。
The mechanics of vacuum preloading was discussed by contrast of vacuum preloading and heaped preloading . the factors affecting the result of vacuum preloading for ground consolidation were as follows : the geological conditions of site , the intensity of vacuum pumping , the condition of underground water and installation of vertical drainage line . through analysis of these factors , some conceptions and design principles were proposed for vacuum preloading 在此基础上，通过堆载预压与真空预压的对比阐述了真空预压加固地基机理，分析了影响真空预压加固地基最终加固效果的各个因素：场地地质条件、抽真空作用强度、地下水赋存情况及竖向排水体的设置等。
Jet grouting is a foundation treatment method that a high - velocity grout , which is forced under high pressure out of a nozzle , cuts into the soil to form a cylindrical soil - cement solidification , and with the result of that the bearing capacity of the foundation is enhanced and the settlement and the differential settlement are reduced . this process is widely used in constructional engineering , highway bridge , coal mine and railway bed 旋喷注浆法可在地层深处将水泥浆液等以高压旋转冲切土体,形成水泥土圆柱加固体,构成旋喷桩复合地基,以达到加固地基,提高承载力和减少建筑物的沉降和不均匀沉降的目的,在我国建筑工程、公路桥梁、煤矿和铁路路基等建设工程中应用极为广泛。
Based on the results from both laboratory test and field application of vacuum preloading it can be concluded that soil is water - saturated in the processes of vacuum consolidation or vacuum preloading . thus , the consolidation properties in negative - pressure area cannot be calculated by using the theory based on non - saturation soil . negative pore - water pressure and suction were specified 在室内试验及现场试验基础上，证明真空预压加固地基过程中，负压区土体仍是饱和的，不能用非饱和土理论来计算负压区的固结性状，并辨析了负压与吸力的概念。
The characteristics of high pressure gyratory sprayed pumping discusses is presented , which is applicable in wide range of scope and ground layers , convenient for construction , long durability , wide source of materials . mechanism for subgrade strengthening : complex foundation of cement solid and earth between piles was formed by pulsant load of flowing pressure and spraying flow , water wallop , cavitation phenomenon , water wedge effect , extrusion force and air flow agitation etc so as to enhance foundation bearing force and reduce settlement and deformation 高压旋喷注浆技术具有适用范围、适用地层较广，施工方便，耐久性好，材料广阔等特点；其加固地基机理主要是通过流动压、喷射流的脉动负荷、水块的冲击力、空穴现象、水楔效应、挤压力、气流搅动等效应形成水泥固结体与桩间土的复合地基，从而提高地基承载力，减少沉降变形。
