Chapter 3 Improving Site Soils for Foundation Use
Chapter 3 Improving Site Soils for Foundation Use
3.1 Introduction This chapter will focus on several of the more widely used methods of improving soils for bearing capacity. ■ An extremely large number of methods have been used and /or reported in the literature. ■ At an individual site one may use a mix of several methods to achieve the desired result. Means to obtain a significant increase in the bearing capacity of a soil-can be achieved by altering the soil properties of cohesion c or density p
3.1 Introduction ▪ This chapter will focus on several of the more widely used methods of improving soils for bearing capacity. ▪ An extremely large number of methods have been used and /or reported in the literature. ▪ At an individual site one may use a mix of several methods to achieve the desired result. ▪ Means to obtain a significant increase in the bearing capacity of a soil-can be achieved by altering the soil properties of Φ,cohesion c or density ρ
Approaches to soil property modification Mechanical stabilization Compaction ■Preloading ■.Drainage Densification using vibratory equipment Use of the situ reinforcement-sometimes called composite ground ◆ Grouting Use of geotextiles Chemical stabilization
Approaches to soil property modification ▪ Mechanical stabilization ▪ Compaction ▪ Preloading ▪ Drainage ▪ Densification using vibratory equipment ▪ Use of the situ reinforcement-sometimes called composite ground ▪ Grouting ▪ Use of geotextiles ▪ Chemical stabilization
3.2 Lightweight and Structural Fills A method that allows construction of relatively light structures on very soft base soil is to use either a lightweight fill or a carefully placed structural fill onto which the foundation is placed. Lightweight fills may use expanded shale, certain industrial slags,and fly ash.These 淘 materials may be mixed with sand and/or gravel to produce a fill of the desired density and durability. EPS (expanded polystyrenc)fill can be used for embankment in highway engineering. 超
3.2 Lightweight and Structural Fills ▪ A method that allows construction of relatively light structures on very soft base soil is to use either a lightweight fill or a carefully placed structural fill onto which the foundation is placed. ▪ Lightweight fills may use expanded shale, certain industrial slags, and fly ash. These materials may be mixed with sand and/or gravel to produce a fill of the desired density and durability. ▪ EPS (expanded polystyrenc) fill can be used for embankment in highway engineering
