A nine pile group consists of 0.30m diameter friction concrete piles 12m long. The piles are driven into clay having an unconfined compressive strength of 180kPa and the unit weight of clay is 18kN/m3. The spacing of piles is 0.75m center to center. Assuming a bearing capacity factor of Nc = 9, a= 1.0. Which of the following most nearly gives the allowable group pile capacity based on individual pile failure using a factor of safety of 3.

A nine pile group consists of 0.30m diameter friction concrete piles 12m long. The piles are driven into clay having an unconfined compressive strength of 180kPa and the unit weight of clay is 18kN/m3. The spacing of piles is 0.75m center to center. Assuming a bearing capacity factor of Nc = 9, a= 1.0. Which of the following most nearly gives the allowable group pile capacity based on individual pile failure using a factor of safety of 3.

Principles of Foundation Engineering (MindTap Course List)

9th Edition

ISBN:9781337705028

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter12: Pile Foundations

Section: Chapter Questions

Problem 12.12P

See similar textbooks

Similar questions

A nine pile group consists of 0.30m diameter friction concrete piles 12m long. The piles are driven into clay having an unconfined compressive strength of 180kPa and the unit weight of clay is 18kN/m3. The spacing of piles is 0.75m center to center. Assuming a bearing capacity factor of Nc = 9, a= 1.0. Which of the following most nearly gives the minimum pile spacing in order to achieve 100% efficiency?
A square pile group of 16 piles penetrates through a filled up soil of 3 m depth. The pile diameter is 250 mm and pile spacing is 0.75 m. The unit cohesion of the material is 18 kN/m² and the unit weight of the soil is 15 kN/m². Compute the drag down force on the group.
A group of 9 friction piles are arranged in a square grid maintaining equal spacing is all direction. Each piles is of diameter 300 mm and length 7 m. Assume that the soil is cohesionless with effective friction angle = 32°. What is the centre to centre spacing of the piles (in m) for the piles group efficiency of 60%? 100
A group pile has a section of 4 x 4 with each having a diameter of 305 mm are embedded in clay. The length of the piles are 12 m and the spacing between the piles (d) are 1.0 m. The recorded soil profile for the ground is shown in Table 1. Propose the allowable load bearing capacity of the pile with a factor of safety of (FS) of 3. (b) TABLE 1 : Soil type and soil parameter Depth Soil parameter 0.0 m to 2.0 m | Unit weight = 17.5 kN/m³ Cohesion = 20 kN/m? 2.0 m to 8.0 m Unit weight = 18.5 kN/m³ Cohesion = 60 kN/m? 8.0 m to 15.0 m Unit weight = 20.1 kN/m³ Cohesion = 80 kN/m?
A group pile has a section of 4 x 4 with each having a diameter of 305 mm are embedded in clay. The length of the piles are 12 m and the spacing between the piles (d) are 1.0 m. The recorded soil profile for the ground is shown in Table 1. Propose the allowable load bearing capacity of the pile with a factor of safety of (FS) of 3. (b) TABLE 1: Soil type and soil parameter Depth Soil parameter Unit weight = 17.5 kN/m³ = 20 kN/m2 0.0 m to 2.0 m Cohesion %3D 2.0 m to 8.0 m Unit weight = 18.5 kN/m³ %3D Cohesion = 60 kN/m? 8.0 m to 15.0 m Unit weight= 20.1 kN/m³ %3D Cohesion = 80 kN/m2
The section of 4*5 group pipe pile, each 15 m in long, embedded in clay layer, the diameter of pile = 403 mm, the center to center spacing of the piles is 700 mm. The clay layer properties, Cu = 60 kN/m2, saturated unit weight = 18.33 kN/m3 Solve the questions 5 - 8. Find the empirical adhesion factor (a) * 1 0.92 0.82 0.74 0.62 None of the above.
A nine-pile group composed of 0.30 m diameter pipe piles is embedded 15 m in clay soil with conditions indicated by the sketch. 1. Det the total capacity if piles act individually 2. Find the total capacity if piles act as a group 3. Det the design load if factor of safety is 3. C = 42.81 kpa a = 0.85 6m C = 57.46 kpa a = 0.75 6m C = 95.76 kpa a = 0.5 Nc = 8 3m 0.75m 1-8 0.75m 上tt 0.75m 0.75m
Figure P12.36 shows a 3 5 pile group consisting of 15 concrete piles of 400 mm diameter and 12 m in length. What would be the maximum load that can be allowed on the mat with a factor of safety of 3? The piles have a center-to-center spacing of 1200 mm.
Determine the maximum load that can be allowed on the 450 mm diameter pile shown in Figure P12.9, with a factor of safety of 3. Use the α method and Table 12.11 for determining the skin friction and Eq. (12.20) for determining the point load.
A group of piles as shown on the figure has a cross section of 0.30 m x 0.30 m. It has a total length of 15 m. The piles are embedded in a homogeneous saturated clay with Cu = 70 kPa. Unit weight of clay is 18.8 kN/m³ and the ground water table is located at a depth of 18 m. below the ground surface. Factor of safety = 4. Compute the allowable load- bearing capacity of the group of pile acting as individual piles. Qall Clay Cu70 kPa 70 15m 56 m- LI-2.74 m -Lz=3,96- Ans. 2816.10 kN
The vertical static load of single pile is tested in a project, the bearing capacity of the three piles is 880KN, 860KN, 890kN respectively. According to the code of the pile foundation, the characteristic value of bearing capacity of the single pile is R. which value is closest to the R? () A 438 kN; B 498 KN; C 588 kN; D 638 KN.
A group of 16 piles of 50 cm diameter in arranged with a centry to centre sporing of 1.0 m. The piles are 9 m long and are embedded in soft stay with cohesion 30kN / (m^5) Bearing resistance may be neglected for the piles-Adhesion factor is 0.6. Determine the ulti mate Load capacity of the pile group.