Sheet pile presentation
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This document outlines the use and design of sheet piles in civil engineering, detailing their applications, advantages, and disadvantages. It covers construction methods, types of sheet piles, and provides specific design calculations for cohesive and cohesionless soils. Practical examples and design procedures for anchored sheet piles are also included, highlighting the necessary calculations and considerations for effective implementation.
![SOLUTION
Design length of sheet pile:
Calculate lateral earth pressure coefficients:
Ka = tan (45-/2) = 0.333
Kp = tan (45-/2) = 3
The lateral earth pressure at bottom of excavation is
pa = Ka h = 0.333*115*10 = 383.33 psf
The active lateral force above excavation
Ha1 = pa*h/2 = 383.33*10/2 = 1917 lb/ft
The depth a = pa / (Kp-Ka) = 383.3 / [115*(3-0.333)] =1.25 ft
The corresponding lateral force
Ha2 = pa*a/2 = 383.33*1.25/2 = 238.6 lb/ft
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Sheet pile presentation
- 1. 1
- 2. Course Instructor Md. Hishamur Rahman Faculty, Department Of Civil Engineering, IUBAT 2
- 3. GROUP: 03 GROUP MEMBERS GROUP MEMBERS 3 SL# NAME ID 01 NOOR E JANNAT 13106166 02 NUR AHMED ZUBAIR SHATU 13206064 03 MINTU MIAH 13206095 04 MD. ABDUL ALIM 13206097 05 MD. MAHADI NAWAZ 13206109 06 S. M. MEHEDI HASAN 13206112 07 MD. SHAMIM REZA 13206010 08 PIAS ROY CHOWDHURY 13306089 09 MD. OSMAN GONI 13306120 10 ATIQUR RAHMAN 13306127 11 MOTIUR RAHMAN 13306008
- 4. 4 SHEETPILE
- 5. PRESENTATION OUTLINE 1. Introduction 2. Use of sheet piles 3. Advantages 4. Disadvantages 5. Types of sheet piles 6. Construction methods 7. Design of sheet pile in cohesive soil 5
- 6. SHEET PILE 6
- 7. Sheet piling is an earth retention and excavation support technique that retains soil, using sheet sections with interlocking edges. Sheet piles are installed in sequence to design depth along the planned excavation perimeter or seawall alignment. Sheet pile is act as a temporary supportive wall that been driven into a slope or excavation to support the soft soils collapse from higher ground to lower ground. 7
- 8. Use of sheet piles * Retaining walls * Bridge abutments * Tunnels * Pumping station * Water treatment plants * Basements * Underground car parks * Port facilities * Locks and dams * Waterfront structures * Piled foundations * Excavations and trenches * Cofferdams * Ground water diversion * Barrier for ground water treatment systems * Containment walls * Flood protection * Coastal protection * Tunnel cut and cover * Bulkheads and seawalls * Weir walls * Slope stabilization * Landfill
- 9. ADVANTAGES 1. Provides high resistance to driving stresses. 2. Light weight. 3. Can be reused on several projects. 4. Long service life above or below water with modest protection. 5. Easy to adapt the pile length by either welding or bolting. 6. Joints are less apt to deform during driving 9
- 10. DISADVANTAGES 1. Sections can rarely be used as part of the permanent structure. 2. Installation of sheet piles is difficult in soils with boulders or cobbles. In such cases, the desired wall depths may not be reached. 3. Excavation shapes are dictated by the sheet pile section and interlocking elements. 4. Sheet pile driving may cause neighborhood disturbance. 5. Settlements in adjacent properties may take place due to installation vibrations 10
- 11. TYPES OF SHEET PILE Several types of sheet piles are commonly used in construction a) Wooden sheet piles b) Precast concrete sheet piles c) Steel sheet piles d) Aluminum sheet piles 11
- 12. 12 Various types of wooden and concrete sheet piles
- 13. Construction method Sheet pile may be divided into two basic categories. 1. Cantilever 2. Anchored Construction methods generally can be divided into two categories. a) Backfilled structure b) Dredged structure 13
- 14. CONSTRUCTION METHODS Sequence for backfilled structure: step 1: Dredged the situ soil in front and back of the proposed structure. step 2: Drive the sheet piles Step 3: Backfill up to the level of the anchor and place the anchor system. Step 4: Backfill up to the top of the wall 14
- 15. CONSTRUCTION METHODS Sequence for dredged structure Step 1: Drive the sheet piles Step 2: Backfill up to the level of the anchor and place the anchor system. Step 3: Backfill up to the top of the wall Step 4: Dredged the front side of the wall 15
- 16. DESIGN OF SHEET PILE IN COHESIVE SOIL
- 17. Design of sheet pile in cohesive soil Calculating active earth pressure Calculation of active earth pressure above excavation is the same as that of cantilever sheet pile in cohesive soil. The free-standing height of soil is d = 2C/ The lateral earth pressure at bottom of excavation, pa = h – 2C, where is unit weight of soil. The resultant force Ha=pa*h/2
- 18. Design of sheet pile in cohesive soil Calculating passive earth pressure For cohesive soil, friction angle, = 0, Ka = Kp = 1. The earth pressure below excavation, p1= p-a= 2C-(h-2C) = 4C-h Assume the embedded depth is D, the resultant force below bottom of excavation is HBCDF = p1*D 18
- 19. Design of sheet pile in cohesive soil Derive equation for D from Mo = 0 Mo = Ha1*y1 – HBCDF* y3 = 0 Where y1 = 2(h-d)/3-(b-d) y3 = h-b+D/2 The equation can be determined with a trial and error process. 19
- 20. Design of sheet pile in cohesive soil Determination of anchor force: 1. Determine anchor force T from Fx = 0 2. Fx = Ha1– HBCDF-T = 0 3. T = Ha1+ Ha2– HCEF Design size of sheet pile: 1. Maximum moment locates at a distance y below T where shear stress equals to zero. 2. T- Ka (y+b-d)2/2=0 3. Solve for y, we have, y = -b+d+2*T/( Ka) 4. The maximum moment is 20
- 21. 5. Mmax = T y - Ka (y+b-d)3/6 6. The required section modulus is S = Mmax / Fb 7. The sheet pile section is selected based on section modulus Design of tie rod and soldier beam Design of tie rod and soldier beam is the same as that of anchored sheet pile in cohesion less soil 21 Design of sheet pile in cohesive soil
- 22. Design procedure 1) Calculate free standing height, d = 2C/ 2) Calculate pa=(h-d) 3) Calculate Ha=pa*h/2 4) Calculate p1=4C-h, 5) Assume a value of D, and calculate HBCDF = p1*D 6) Calculate R= Ha*y1 – HBCDF* y3. 7) Where 8) y1 = 2(h-d)/3-(b-d) 9) y3 = h-b+D/2 22
- 23. Design procedure 10. If R is not close to zero, assume a new D, repeat steps 5 and 6 11. The design length of sheet pile is L=h+D*FS, FS=1.2 to 1.4. 12. Calculate anchored force T = Ha – HBCDF 13. Calculate y = -b+d+2*T/ 14. Calculate Mmax = T y - (y+b-d)3/6 15. Calculate required section modulus S= Mmax/Fb. Select sheet pile section. 16. Design tie rod 17. Design soldier beam. 23
- 24. Design anchored sheet pile in cohesionless soil. Given: Depth of excavation, h = 10 ft Unit weight of soil, g = 115 lb/ft3 Internal friction angle, f = 30 degree Allowable design stress of sheet pile = 32 ksi Yield strength of soldier beam, Fy = 36 ksi Location of tie rod at 2 ft below ground surface spacing, s = 12 ft Requirement: Design length of an anchored sheet pile, select sheet pile section, and design tie rod 24
- 25. SOLUTION Design length of sheet pile: Calculate lateral earth pressure coefficients: Ka = tan (45-/2) = 0.333 Kp = tan (45-/2) = 3 The lateral earth pressure at bottom of excavation is pa = Ka h = 0.333*115*10 = 383.33 psf The active lateral force above excavation Ha1 = pa*h/2 = 383.33*10/2 = 1917 lb/ft The depth a = pa / (Kp-Ka) = 383.3 / [115*(3-0.333)] =1.25 ft The corresponding lateral force Ha2 = pa*a/2 = 383.33*1.25/2 = 238.6 lb/ft 25
- 26. Assume Y = 2.85 ft HCEF = (Kp-Ka) Y2/3 = 115*(3-0.333)*2.852/3 = 830.3 lb/ft y1 = (2h/3-b) = (2*10/3-2)=4.67 ft y2 = (h+a/3-b) = (10+1.25/3-2)=8.42 ft y3 = (h+a+2Y/3) = (10+1.25+2*2.85/3) = 13.15 ft R = Ha1*y1 + Ha2* y2 – HCEF* y3 = 1917*4.67+238.6*8.42-830.3*13.15 = 42.5 lb R closes to zero, D = 2.85+1.25 = 4.1 ft Length of sheet pile, L = 10 + 1.2* 4.1 = 14.9 ft =>Use 15 ft 26
- 27. Calculate anchor force, T = Ha1+ Ha2– HCEF = 1917+238.6-830.3 = 1326 lb/ft Calculate location of maximum moment, y = -b+2*T/( Ka) = -2 ft + 2*1326/(115*0.333) = 6.32 ft Mmax = T y - Ka (y+b)3/6 = 1326*6.32 – 115*0.333*(6.32+2)3/6 = 4.7 kip-ft/ft The required section modulus S= Mmax/Fb = 4.7*12/32 = 1.8 in3/ft Use PS28, S = 1.9 in3/ft Design tie rod, the required cross section area, A = T s / (0.6*Fy) = 1.326*12/(0.6*36) = 0.442 in2. Use1@ ¾” diameter tie rod, A = 0.442 in2. 27
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