Foundation Treatment Method Selection Principle

Foundation Treatment Method Selection Principle

 The soft foundation treatment project must ensure the quality of the project, economic rationality and advanced technology. China has a vast territory, and the engineering geological conditions are ever-changing. The construction machinery conditions, technical level, experience accumulation, and the variety and price of construction materials vary greatly. When selecting the ground treatment method, it must be adapted to local conditions. Specific project analysis should give full play to local advantages. Use local resources. There are many ground treatment methods, each of which has a certain scope of application, limitations, advantages and disadvantages. No ground treatment method is omnipotent. According to the specific project conditions, the appropriate ground treatment method should be determined according to local conditions. Blindness should be overcome when referring to a method of a foreign or external unit, paying attention to regional characteristics. Adapting to local conditions is an important selection principle for the selection of ground treatment methods such as pvd wick drains.

 First, it is determined whether the soft foundation improvement needs to be treated according to the various requirements of the foundation (structure) and the natural foundation conditions. If the natural foundation can meet the requirements of the foundation of the building (structure), natural foundation should be used as much as possible. If the natural foundation does not meet the requirements of the building (structure) to the soft clay foundation, then the scope of the natural formation to be treated and the requirements for foundation treatment need to be determined by vacuum preloading.

       When the natural foundation cannot meet the requirements of the foundation of the building (structure), the superstructure, soft foundation should be considered together. When considering a ground treatment plan, attention should be paid to the interaction of the superstructure, foundation and foundation. It is not only possible to consider the reinforcement of the soft foundation, but also consider whether the upper structure is reasonable and whether the overall rigidity is sufficient. When determining the ground treatment plan, the scheme of treating only the foundation should be considered at the same time, or the combination of strengthening the rigidity of the superstructure and the treatment of the foundation should be selected, otherwise it will not only cause unnecessary waste but may bring about adverse consequences.

       Before the specific soft ground treatment plan is determined, the feasibility study of the ground treatment plan should be carried out according to the conditions of the natural formation, the principle of the foundation treatment method, the experience of the past application, the equipment and the material conditions, and various technically feasible solutions are proposed; Then, the technical, economic, and progress aspects of the proposed multiple schemes are compared and analyzed, and the environmental protection requirements are considered. One or several ground treatment methods are determined. This is also the optimization process of the ground-based treatment plan. Finally, based on the pre-determined ground treatment plan, decide whether to conduct a small field test or conduct a supplementary survey as needed. Then carry out the construction design and then carry out the foundation treatment construction. During the construction process of soft ground improvement, monitoring and testing should be carried out. If necessary, reverse analysis should be carried out. The design can be modified and supplemented according to the situation. The detailed understanding of the natural geological conditions of natural foundations in actual projects is often neglected. Many engineering accidents caused by foundation problems or soft ground treatments fail to achieve the intended purpose, often due to insufficient understanding of the engineering geological conditions. Detailed engineering geological survey is one of the important basis for judging whether the natural foundation can meet the requirements of the foundation of the building (structure). Detailed engineering geological survey data is one of the main basic data for determining a reasonable foundation treatment method if ground treatment is required.

       Through engineering geological survey, investigate the topography and geomorphology of the building site, and identify the geological conditions, including the nature of the rock and soil, the genetic type, geological generation, thickness and distribution range. It is necessary to understand whether there are alums, dark scorpions, ancient rivers, ancient wells and ancient tombs in the foundation. 

For the layer, the degree of weathering and the contact relationship of the stratum should also be ascertained, the geological structure of the natural stratum should be investigated, and the hydrological and engineering geological conditions should be ascertained to determine whether there are any unfavorable geological phenomena: such as landslides, collapses, karst, soil caves, gullies, Debris flow, shore scouring and earthquakes. The physical and mechanical properties of the foundation soil are determined, including: natural gravity, relative density, particle analysis, plasticity index, permeability coefficient, compression coefficient, compression modulus, shear strength, and the like. 

Finally, according to the requirements, the stability and suitability of the site, the uniformity of the foundation, the bearing capacity and the deformation characteristics are evaluated. In addition, it is necessary to emphasize the comparison of multiple schemes for ground treatment. For a specific ground improvement project, there are often several technically feasible ground treatment schemes. The comprehensive analysis of the technology, economy, and schedule, as well as the impact on the environment, should be carried out to optimize the ground treatment plan to obtain a better ground treatment plan.

vacuum preloading

vacuum preloading soft soil treatment work site