Evaluation of Horizontal Displacement of Long Piles Subject to Lateral Loading in Sandy Soil

Transcription

1 195 ; ; ; Evaluation of Horizontal Displacement of Long Piles Subject to Lateral Loading in Sand Soil J Keshavarz J Bolouri Bazaz Abstract In man structures, the applied lateral loads are comparable with gravit loads These tpes of piles which are subject to high lateral load are usuall divided into two categories including long and short piles The general methods to estimate lateral bearing capacit of short and long piles are based on ultimate bearing capacit and allowable horizontal displacement respectivel In the present research, in order to evaluate lateral bearing capacit of piles subjected to horizontal loads, steel pipes which were embedded in sand soil to simulate piles in the laborator A wide range of laborator tests were performed to investigate the behavior of long piles with different lengths and diameters The test results were compared with three different theories including Modulus of Subgrade Reaction, Elastic and k hmax approaches The experimental results reveal that k hmax approach is more suitable for determination of horizontal displacement and also estimation of lateral bearing capacit for long piles Ke Words Long piles, Lateral load, Horizontal displacement, Cohesionless soil 9/2/ 9/2/1 bolouri@umacir :

2 66 Christensen[11] Prasad and Chari [8] 1 12 : 1/8 1 2 Zhang et al [12] [1] (Fix Head Kumar et al [1] (Free Head p- [2-8] Murugan et al [1] [1] [9] [1] 195

3 67 (kpa E s (m [19] 2 n h (kn/m [1] 1 L/T L/T 2 [ ] 1 K K r > 1-2 r < 1-2 [1] 2 ( L/B>6 S H > 5 L/B<6 [] S H < 5 [16] L > BK 6 L < BK 6 [17] 5 L > L C L > L C / [18] 6 k h k h p d EI p dx : (6 T K S r (E 2 P I P / n h (E I / E B P P 25 H (L / B(E P / E s K L (E / E P s 25 c (E PI P / Es s T ( ( (5 d dx kh EI EI x p (7 (5 ( (K ( (S H K r (L c [16] (9 I P (kpa L n h (m E P B (m (kn/m

4 68 n h Q T (9 T (kn (m Q E s g N x h [1] Q N h (18 g L 2 E s N h =n h (I ph F p e I L pm ( k h I pm / F p N h E s I ph (17 n h (18 X A g : EI Q T g BEI 2 M T x Z T L T k T h EI A Z max B A B B (x (1 : ( B A (1 (11 (12 (1 (1 ( A g e Qg : M g Z max Q g (1 (12 Z (11 (x [2] x A Q T g EI B M T g EI 2 (16 /2 k h [9] B A 1/62 2/5 (z= =2 k h [21-2] k hmax k h 52 k h max 8 (19 EI

5 Q g k hmax [2] 1667B ( (2 [2] k hmax k hmax (ksf ( [25] k h (21 n h =k h Q g EI A T Q g T (21 A =25 k hmax [9] 1 (kn/m 18 (% ( E s (MPa 16 (

6 7 6 8 ( (kg/m (GPa (mm (mm [1] [26] 2 [26] 27 [26]

7 K hmax 71 Al-L*D* Ga-L*D* Al Ga L D (cm (16-21/7 (mm Ga-L-D kn/m kn/m ( 8 6 (9 ( (7 Sub-Re (9 Elastic Sub-Re(nh ( 27 2

8 72 Test No: Ga-L8-D Kh max (min Method Kh max (max Method = kn/m Displacement (mm (9 Test No: Ga-L8-D217- Elastic Method Sub-Re Method Sub-Re (nh Method ( 6 2 = kn/m Displacement (mm 5 ( ( Test No: Ga-L8-D217-1 Kh max (min Method Kh max (max Method = kn/m Displacement (mm 6 Test No: Ga-L8-D27- Elastic Method Sub-Re Method Sub-Re (nh Method (6 (5 21/7 2 = kn/m Displacement (mm (5

9 7 Test No: Al-L8-D22- Kh max (min Method Kh max (max Method (6 7 8 (7 22 Test No: Al-L8-D28- Elastic Method 25 Sub-Re Method Sub-Re (nh Method 1/ = kn/m Displacement (mm 9 (8 2/8 6 8 (1 (9 =18 kn/m 1 7

10 7 6 ( (1 (1 8 6 (16 ( = kn/m Test No: Al-L8-D28-5 Test No: Al-L6-D28- Test No: Al-L-D Displacement (mm kn/m ( ( (12 2/8 27

11 /8 kn/m = kn/m 6 (19 1/8 ( Test No: Ga-L8-D27- Test No: Ga-L8-D Displacement (mm kn/m /8 ( = kn/m Test No: Al-L6-D28 F= (Vertical position F=12 N F=2 N F=28 N Horizontal displacement (mm 21/7 6 16

12 76 2 Ga- Ga-L-D217 Ga-L6-D27 Ga-L-D27 L6-D (7 1/8 6 Test No (kn/m (mm Al-L-D22 1 Al-L6-D Al-L8-D22 17 Al-L-D28 1 Al-L6-D28 Al-L8-D28 1 Ga-L Ga-L8-D Label Ep Es Broms Poulos & Davis Bierschwale Dobr Davies & Budhu Poulos & Hull kn/m GPa MPa L/T Kr L/B SH BK 6 Lc Ga-L-D Ga-L6-D Ga-L8-D Ga-L-D Ga-L6-D Ga-L8-D Al-L-D Al-L6-D Al-L8-D Al-L-D Al-L6-D Al-L8-D

13 77 ( ( (11 (9 6 (

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