Construction Planning, Equipment, CHAPTER GEOTECHNICAL ...

1 1 A. J. Clark School of Engineering Department of Civil and Environmental EngineeringSixth EditionCHAPTER4bConstruction planning , equipment , and MethodsGEOTECHNICAL MATERIALS, GEOTECHNICAL MATERIALS, compaction , AND STABILIZATIONCOMPACTION, AND STABILIZATIONByByDr. Ibrahim AssakkafDr. Ibrahim AssakkafENCEENCE420 420 Construction equipment and MethodsConstruction equipment and MethodsSpring 2003 Spring 2003 Department of Civil and Environmental EngineeringDepartment of Civil and Environmental EngineeringUniversity of Maryland, College ParkUniversity of Maryland, College ParkCHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No.

2 75 Same weight but different volume. MATERIAL PROPERTIESMATERIAL PROPERTIES2 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 76 Example 4 Example 4 The soil borrow material to be used to The soil borrow material to be used to construct a highway embankment has a construct a highway embankment has a mass unit weight lb per cu ft (mass unit weight lb per cu ft (pcfpcf) ) and water content of 8%, and specific and water content of 8%, and specific gravity of soil solids is The gravity of soil solids is The specifications require that the soil be specifications require that the soil be compacted to dry unit weight of 112 compacted to dry unit weight of 112 pcfpcfand that the water content be held to and that the water content be held to 13%.

3 13%. CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 77 Example 4 (cont d)Example 4 (cont d)a)a)How many cubic yards of borrow are How many cubic yards of borrow are required to construct an embankment required to construct an embankment having a 250,000having a 250,000--cucu--yd net section yd net section volume?volume?b)b)How many gallons of water must be How many gallons of water must be added per cubic yard of borrow material added per cubic yard of borrow material assuming no loss by evaporation and one assuming no loss by evaporation and one gallon of water equals lb?gallon of water equals lb?c)c)If the compacted fill becomes saturated at If the compacted fill becomes saturated at a constant volume, what will be the water a constant volume, what will be the water content and mass unit weight of the soil?

4 Content and mass unit weight of the soil?3 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 78 Example 4 (cont d)Example 4 (cont d)Borrow:Borrow:Embankment: , ,ftlb +=+==== dsG () ( ) , ,ftlb +=+=== dd CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 79 Example 4 (cont d)Example 4 (cont d)(a):(a):(b):(b):ydcu 315,000yd)cu (250,0 Required Borrow of Unit WBank eightDry Unit W CompactedFactor Shrinkage=====()lb 000,280,98yardft 27yard 000, needed Water ofWeight :embankmentin neededWater 33333= == = d 4 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No.

5 80 Example 4 (cont d)Example 4 (cont d) CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 81 Example 4 (cont d)Example 4 (cont d)(b) continued:(b) continued:()borrow ydcu gal lb/gal lb120 ydcu lb120yard 315,000lb 450,809,37 WaterdReq' of Gallonslb 450,809,37550,470,60000,280,98 Required Water Additional ofWeight lb 550,470,60yardft 27yard 000, Borrow from Water ofWeight :borrow fromWater 333333===== == == = d 5 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 82 Example 4 (cont d)Example 4 (cont d)(c):(c):If the fill becomes saturated all voids between the solid soilIf the fill becomes saturated all voids between the solid soilparticles are filled with water.

6 Therefore, the total weparticles are filled with water. Therefore, the total weight is ight is increased by the added weight of water:increased by the added weight of water:WaterAIRSoilWeight air = 0 Weight water = WwTotal weight WWeight soil solids WsVolume air VaVolumesoil solidsVsVolumewater VwVolumevoids VvTotalvolumeVAdditionalWater to replace AirCHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 83 Example 4 (cont d)Example 4 (cont d)Total volume includesTotal volume includesAirAirWaterWaterSolids Solids 6 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 84 Example 4 (cont d)Example 4 (cont d)(c): (c): continuedcontinuedWeight of extra waterWeight of extra water::333ft ) ( ======= =vwwwwssswsssVWVGWVVWG ) (lb ) ( ++===+===== swwwwWWVWCHAPTER 4b.

7 GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 85 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROL7 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 86 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROLThe engineering properties of most soils can be improved by is the art of mechanically 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 87 NON-COHESIVESMALL GRAINED <#200 MESH SIEVECOHESIVESOIL TYPESSOIL TYPES8 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 88 ORGANIC SOILSWill usually have to remove before TYPESSOIL TYPESCHAPTER 4b.

8 GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 89 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROLB efore the specifications for a Before the specifications for a project are prepared project are prepared representative representative soil samplessoil samplesare are usually collected and tested in usually collected and tested in the laboratory to determine the laboratory to determine material properties. material properties. 9 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 90 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROLSOIL CLASSIFICATION SOIL CLASSIFICATION ((AtterburgAtterburgLimits)Limits)LL - Liquid limitPL - Plastic limitPI - Plasticity IndexCHAPTER 4b.

9 GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 91 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROLSOIL LIMITSSOIL LIMITS10 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 92LL - Liquid limitis the water content of a soil when it passes from the plastic to liquid CLASSIFICATIONSOIL CLASSIFICATIONCHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 93LL - Liquid limitNon-cohesive or sandy soils have low LLs -- less than soils have LLs ranging from 20 to CLASSIFICATIONSOIL CLASSIFICATION11 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No.

10 94PL - Liquid limitis the lowest water content at which a soil remains diameter threadSOIL CLASSIFICATIONSOIL CLASSIFICATIONCHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 95PI - Plastic IndexPI = LL - PLThe higher the PI the more clay that is present in the CLASSIFICATIONSOIL CLASSIFICATION12 CHAPTER 4b. GEOTECHNICAL MATERIALS & COMPACTIONENCE 420 AssakkafSlide No. 96 compaction SPECIFICATION compaction SPECIFICATION AND CONTROLAND CONTROLN ormal testing would include Normal testing would include graingrain--size analysissize analysisbecause the because the size of the grains and the size of the grains and the distribution of those sizes are distribution of those sizes are important properties, which important properties, which affect a soil's a soil's 4b.