Pile foundations_Advanced Construction TechnologyA Makwana
Pile foundation is that type of deep foundation in which the loads are taken to a low level by means of vertical members which may be of timber, concrete or steel.
Pile foundations_Advanced Construction TechnologyA Makwana
Pile foundation is that type of deep foundation in which the loads are taken to a low level by means of vertical members which may be of timber, concrete or steel.
OUTLINE:
Introduction
Shoring Process
Effective Beam Flange Width
Shear Transfer
Strength Of Steel Anchors
Partially Composite Beams
Moment Capacity Of Composite Sections
Deflection
Design Of Composite Sections
Sheet Piles; Advantages, Types and Methods - Sheet piles are commonly used for retaining walls, land reclamation, underground structures such as car parks and basements, in marine locations for riverbank protection, seawalls, cofferdams, and so on
• A retaining wall construction method in which walls are constructed with small gaps between adjacent piles. The size of the space is determined by the nature of the soils.
• الخوازيق الساندة بيتم تنفيذها قبل حفر الموقع لأن وظيفتها سند جوانب الحفر
ولايتم الحفر قبل مرور 28 يوم على تنفيذ آخر خازوق ساند
• وبيتم استخدام الخوازيق البنتونيت فى حالة وجود مياة جوفية بمنسوب أعلى ممنسوب الحفرن
• وبيتم تنفيذ الخوازيق البنتونيت أولا ثم بين كل خازوقين بنتونيت يتم تنفيذ خازوق خرسانى بحيث يتداخل بالخوازيق البنتونيت أثناءالتنفي ولا تأثير انشائي له سواء الاملاء وسند التربة
Design elevated tanks Dynamic Analysis
Response spectrum Spring mass model
Examples solved according to
Egyptian - European -Code
Models High tanks – floor-design
Roofed - exposed - concrete - metal
1. High-tank reinforced concrete roofed propped on a framework (4) columns
2. - High-roofed reinforced concrete tank propped on a framework (6) columns
3 - High-roofed reinforced concrete tank propped on Core Reinforced Concrete
4 - Ground-roofed metal circular tank propped directly on the soil
5 - Ground tank Exposed reinforced concrete circular propped directly on the soil
6. - Ground tank Exposed reinforced concrete rectangular propped directly on the soil
OUTLINE:
Introduction
Shoring Process
Effective Beam Flange Width
Shear Transfer
Strength Of Steel Anchors
Partially Composite Beams
Moment Capacity Of Composite Sections
Deflection
Design Of Composite Sections
Sheet Piles; Advantages, Types and Methods - Sheet piles are commonly used for retaining walls, land reclamation, underground structures such as car parks and basements, in marine locations for riverbank protection, seawalls, cofferdams, and so on
• A retaining wall construction method in which walls are constructed with small gaps between adjacent piles. The size of the space is determined by the nature of the soils.
• الخوازيق الساندة بيتم تنفيذها قبل حفر الموقع لأن وظيفتها سند جوانب الحفر
ولايتم الحفر قبل مرور 28 يوم على تنفيذ آخر خازوق ساند
• وبيتم استخدام الخوازيق البنتونيت فى حالة وجود مياة جوفية بمنسوب أعلى ممنسوب الحفرن
• وبيتم تنفيذ الخوازيق البنتونيت أولا ثم بين كل خازوقين بنتونيت يتم تنفيذ خازوق خرسانى بحيث يتداخل بالخوازيق البنتونيت أثناءالتنفي ولا تأثير انشائي له سواء الاملاء وسند التربة
Design elevated tanks Dynamic Analysis
Response spectrum Spring mass model
Examples solved according to
Egyptian - European -Code
Models High tanks – floor-design
Roofed - exposed - concrete - metal
1. High-tank reinforced concrete roofed propped on a framework (4) columns
2. - High-roofed reinforced concrete tank propped on a framework (6) columns
3 - High-roofed reinforced concrete tank propped on Core Reinforced Concrete
4 - Ground-roofed metal circular tank propped directly on the soil
5 - Ground tank Exposed reinforced concrete circular propped directly on the soil
6. - Ground tank Exposed reinforced concrete rectangular propped directly on the soil
SOIL-SHEET PILE INTERACTION - PART II: NUMERICAL ANALYSIS AND SIMULATIONIAEME Publication
This study investigates the interaction between soil and the embedded sheet pile wall at the interface which is not generally well captured in the conventional theoretical and design methods. This was implemented by carrying out numerical analysis to study the behavior and response of the
two contacting materials using incremental loading technique. The effects of the interaction were investigated in terms of deformations and stress distributions, all based on Finite Element technique. Numerical analyses of sheet pile wall embedded in homogenous and heterogeneous soil strata were
performedindependently. The results showed variation between the theoretical conventional design approach and that of the numerical analysis for both anchored and cantilevered sheet pile walls
Coupling Beams
in High-Rise Core-Wall Structures
Shear wall structures are most important lateral-force-resisting-systems that have been shown to be
very efficient in resisting seismic loads. But previous earthquake damages showed that the coupling
beams were easily damaged in the earthquake and it was often used as an energy dissipation part in structures.
Design and Structural Excel sheet programs
Topics and articles in Structural Engineering
In design - and public safety local and international
engineering codes And maintain the integrity of
building and the lives of vacancies
Abstract --- Graspless manipulation is easily interfered by external disturbances because the manipulated object is not completely held by a robot hand and supported by an environment such as a floor. Thus it is important to ensure the manipulation
is executed robustly against some disturbances. In our works, we have proposed a rigid-body-based analysis of indeterminate contact forces for quasi-static graspless manipulation, and also joint torque optimization for robotic hands. The joint torques
of the robot is determined in consideration of some robustness of manipulation against disturbances, which include changes or estimation errors of friction. In the analysis of contact forces in quasi-statics, we consider a kinematic constraint on static friction to exclude infeasible sets of frictional force, with considering treatment of kinetic friction. We also propose new objective functions for computing optimal joint torques in both static and quasi-static graspless manipulation. Some numerical samples of both applications are shown to verify our proposed methods.
الأبنية المعلقة بكبلات وشدادات الى اعلى جدران كور بيت الدرج المركزي
اعمدة على محيط الواجاهات فقط
مقاومة الرياح والزلال بجدران كور الخرسانة فقط
cable suspended building-
p- delta analysis - تحليل اعمدة الاطارات لمقاومة عزوم الانتقال الافقي من الزل...Dr.youssef hamida
P- DELTA ANALYSIS
- تحليل اعمدة الاطارات لمقاومة عزوم الانتقال الافقي من الزلازل P - دلتا
نحتاج تحليل p - دلتا عندما الأعمدة لا تشارك في مقاومة الزلازل فقط الجدران القصية تقاوم كامل قوى القص القاعدي والأعمدة تقاوم حمولات شاقولية فقط والعزم الناج من انتقال افقي لاطارات الأعمدة
Techniques for the Seismic Rehabilitation of Existing Buildings - طرق تاهيل ...Dr.youssef hamida
Techniques for the Seismic Rehabilitation of Existing Buildings - طرق تاهيل وتدعيم الابنية القديمة لمقاومة الزلازل.
تدعيم كل انواع الابنية الخرسانة واالستيل والخشب لمقاومة الزلازل
د. يوسف حميضة-حلب تصميم المباني لمقاومة الزلازل - -محاضرة تأهيل- نقابة المهن...Dr.youssef hamida
Designing Buildings to Resist Earthquakes. Lecture for Qualification of Engineers, Syrian Engineers Syndicate - Aleppo Branch
د. يوسف حميضة - تصميم المباني لمقاومة الزلازل محاضرة تأهيل المهندسين نقابة المهندسين السوريين - فرع حلب
امثلة محلولة وفق الكود السوري
support in bridges - مساند الجسور والكباري- د حميضة.pdfDr.youssef hamida
support in bridges- انواع مساند الجسور والكباري د حميضة
مساند الجسور والكباري د حميضة أنواع المساند هي:
المسند الثابت: يتحمل القوى الأفقية والقوى الرأسية
المسند المنزلق: يتحمل القوى الرأسية فقط، وهذا يعني أنه إذا أثرت عليه قوة أفقية يتم إزاحته أفقياً
ا المسند الموثوق: يتحمل القوى الأفقية والقوى الرأسية والعزوم
الكود الأمريكي وتباعد فواصل التمدد مع او دون حساب جهود الحرارة
ومتى تحتاج الى حساب تأثير الحرارة على الهيكل و التباعدات الأعظمية المسموحة مع حساب الحرارة فقط مع فواصل حرارية او بدون
ACI 2243r-95-Expansion Joint Spacing- Dr hamida.pdf
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
CW RADAR, FMCW RADAR, FMCW ALTIMETER, AND THEIR PARAMETERSveerababupersonal22
It consists of cw radar and fmcw radar ,range measurement,if amplifier and fmcw altimeterThe CW radar operates using continuous wave transmission, while the FMCW radar employs frequency-modulated continuous wave technology. Range measurement is a crucial aspect of radar systems, providing information about the distance to a target. The IF amplifier plays a key role in signal processing, amplifying intermediate frequency signals for further analysis. The FMCW altimeter utilizes frequency-modulated continuous wave technology to accurately measure altitude above a reference point.
28. 28
Steel sheeting provides resistance during installation stresses. The sheets must be
driven into the ground and they have high resistance to the force of being driven
down.
It is extremely light weight and makes it easier to lift and handle.
Steel sheeting is reusable and recyclable.
There is a long life for it both above and under water. It only requires light protection
to keep it maintained.
The pile length is easily adaptable and can be welded or bolted to make it work.
They have stronger joints that can withstand the force of being driven into place.
29. 29
Steel Sheet Piling Construction Steps
First, lay out the sheets in sections to make sure that the piles will interlock
correctly.
Drive each sheet to the depth that has been mapped out.
Then drive the second sheet that has the interlocks between the first sheet and
the second locked sheet.
Repeat until the wall is completed.
If the wall requires complex shapes use connector elements to ensure that the
integrity of the wall is maintained.
Vibratory hammers are used for the installation of steel sheet piles. An impact
hammer is used if the soil is too dense for the vibratory hammer.
At sites where vibrations are not recommended the sheets are pushed into place
using hydraulics.
38. 38
-----------------------------
Sheet Pile Walls...
Sheet pile walls are another method for construction of basements and temporary
excavations, however they are increasingly being used as permanent structures with
the correctly specified surface coating.
الخوازيق,واألوتادالساندةالحفر جوانب سند وظيفتها ألن الموقع حفر قبل تنفيذها بيتم
مرور قبل الحفر واليتم82ساند خازوق آخر تنفيذ على يوم
التأسيس تربة لمنسوب واليصل الحفر بقيمة مرتبط طوله الساند والخازوق
.
41. 41
For free earth support method
the soils at the lower part of piling is incapable of inducing effective restraint so that it
would not result in negative bending moments. In essence, the passive pressures in front
of the sheet piles are insufficient to prevent lateral deflection and rotations at the lower
end of piling. No passive resistance is developed on the backside of the piling below the
line of excavation.
For fixed earth support method
, the piling is driven deep enough so that the soil under the line of excavation provides the
required restraint against deformations and rotations. In short, the lower end of piling is
essentially fixed.
42. 42
Anchored sheet pile wall
Anchored sheet pile wall in cohesionless soil
Anchored sheet pile wall in cohesive soil
Design using free earth support method
1. Sheet pile is rigid, and lateral deflection is small.
2. The lateral pressure distributes according to Rankine’s or Coulomb’s theories
3. The tie back is strong, and sheet pile rotate about the tie rod anchor point at failure
4. Bottom of sheet pile is free to move.
43. 43
embedded depth can be determined by summarizing horizontal earth pressures and moments about
the anchor.
Fx = 0 [1]
Mo = 0 [2]
the lateral earth pressure is a function of embedded depth. Both equations are highly nonlinear. A
trial and error method has to be used to determine the root.
r structural design, the sheet pile needs to be able to withstand maximum moment and shear from
lateral pressure. A structural analysis needs to be done to determine maximum moment and
shear.
44. 44
Anchored sheet pile wall in cohesionless soil
Design length of sheet pile
Calculating active earth pressure
The method for calculating active earth pressure is the same as that in cantilever sheet pile wall. The
lateral forces Ha1 is calculated as
Ha1= Ka h2
/2+q Ka h
The depth a can be calculated as
a = pa / (Kp-Ka)
The lateral forces Ha2 can be calculated as
Ha2=pa*a/2
Calculating passive earth pressure
The slope from point C to E in the figure above is (Kp-Ka). The passive earth pressure at a depth Y
below a is calculated as
Pp = (Kp-Ka) Y
45. 45
The passive lateral force
HCEF = (Kp-Ka) Y2
/2
Derive equation for Y from Mo = 0
Mo = Ha1*y1 + Ha2* y2 – HCEF* y3 = 0
Where
y1 = (2h/3-b)
y2 = (h+a/3-b)
y3 = (h+a+2Y/3)
The equation needs to be determined by a trial and error process.
Determine anchor force T from Fx = 0
Fx = Ha1+ Ha2– HCEF-T = 0
Then,
T = Ha1+ Ha2– HCEF
Design size of sheet pile
The structural is the same as cantilever sheet piles in cohesionless soil.
Maximum moment locates at a distance y below T where shear stress equals to zero.
T- Ka (y+b)2
/2=0
Solve for y, we have, y = -b+2*T/( Ka)
The maximum moment is
Mmax = T y - Ka (y+b)3
/6
The required section modulus is S = Mmax / Fb
The sheet pile section is selected based on section modulus
46. 46
Design of tie rod and soldier beam
sheet pile design above is based on a unit width, foot or meter. The tie back force T calculated from
sheet pile design is force per linearly width of sheet pile. The top of sheet pile often supported with
soldier beams and tie rods at certain spacing.
Assume the spacing of tie rod is s, the tension in the rod is T times s. The required area of tie rod is
A = T s / Ft
Where Ft is allowable tensile stress of steel and is equal to 0.6Fy in AISC ASD design.
oil beam is designed as a continuous beam that subjected to tie back force T. The maximum moment
in the soldier beam is calculated from structural analysis. The required section modulus is equal to S
= Mmax / Fb.
Design procedure
1.Calculate lateral earth pressure at bottom of excavation, pa and Ha1.
pa = Ka H, Ha1=pa*h/2
2.Calculate the length a, and Ha2.
a = pa / (Kp-Ka), Ha2=pa*a/2
3.Assume a trial depth Y, calculate HCEF.
HCEF = (Kp-Ka) Y2
/3
4.Let R = Ha1*y1 + Ha2* y2 – HCEF* y3
y1 = (2h/3-b)
y2 = (h+a/3-b)
47. 47
y3 = (h+a+2Y/3)
Substitute Y into R, if R = 0, the embedded depth, D = Y + a.
If not, assume a new Y, repeat step 3 to 4.
5.Calculate the length of sheet pile, L = h+F.S.*D, FS is from 1.2 to 1.4.
6.Calculate anchored force T = Ha1+ Ha2– HCEF
7.Calculate y = -b+2*T/( Ka)
8.Calculate Mmax = T y - Ka (y+b)3
/6
9.Calculate required section modulus S= Mmax/Fb.
10. Select sheet pile section.
11. Design tie rod
12. Design soldier beam.
48. 48
Example 3. Design anchored sheet pile in cohesionless soil.
Depth of excavation, h = 10 ft
Unit weight of soil, = 115 lb/ft3
Internal friction angle, = 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
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
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
49. 49
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
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 in3
.
Use ¾” diameter tie rod, A = 0.442 in3
.
Design soldier beam:
The maximum moment of a continuous beams with 3 or more span is
M = 0.1*T s2
= 0.1*1326*122
=19.1 kip-ft
Required section modulus, S = M / (0.6*Fy) = 19.1*12/(0.6*36) = 6.4 in3
.
Use W6x15, S = 9.72 in3
.
50. 50
Anchored sheet pile wall 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
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
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.
51. 51
Determine anchor force T from Fx = 0
Fx = Ha1– HBCDF-T = 0
T = Ha1+ Ha2– HCEF
Design size of sheet pile
Maximum moment locates at a distance y below T where shear stress equals to zero.
T- Ka (y+b-d)2
/2=0
Solve for y, we have, y = -b+d+2*T/( Ka)
The maximum moment is
Mmax = T y - Ka (y+b-d)3
/6
The required section modulus is S = Mmax / Fb
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 cohesionless soil.
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.
Where
y1 = 2(h-d)/3-(b-d)
y3 = h-b+D/2
If R is not close to zero, assume a new D, repeat steps 5 and 6
7.The design length of sheet pile is L=h+D*FS, FS=1.2 to 1.4.
8.Calculate anchored force T = Ha – HBCDF
9.Calculate y = -b+d+2*T/
10. Calculate Mmax = T y - (y+b-d)3
/6
11. Calculate required section modulus S= Mmax/Fb. Select sheet pile section.
12. Design tie rod
52. 52
13. Design soldier beam.
Example 4: Design anchored sheet pile in cohesive soil.
Depth of excavation, h = 15 ft
Unit weight of soil, = 115 lb/ft3
Cohesion of soil, C = 500 psf
Internal friction angle, = 0 degree
Allowable design strength of sheet pile = 32 ksi
Yield strength of soldier beam, Fy = 36 ksi
Location of tie rod at 2 ft below ground surface, spacing =12 ft.
Requirement: Design length of sheet pile and select sheet pile section
Solution:
Design length of sheet pile:
The free standing height, d = 2C/ = 2*500/115 = 8.7 ft
The lateral pressure at bottom of sheet pile, pa = (h-d)=115*(10-8.7)=150 psf
Total active force, Ha=pa*h/2 = 150*10/2 = 750 lb/ft
p1=4C-h = 4*550-115*15 = 275 psf
Assume D = 11.5 ft,
HBCDF = p1*D = 3163 lb/ft
y1 = 2(h-d)/3-(b-d) =2 (15-8.7)/3-(2-8.7) = 10.9 ft
y3 = h-b+D/2 = 15-2+11.5/2 = 18.75 ft
R= Ha*y1 – HBCDF* y3 = 5438*10.9-3163*18.75 = -36 lb Close to zero
The length of sheet pile, L = 15 + 1.2*11.5 = 28.8 ft Use 29 ft
Anchored force per foot of wall, T = Ha – HBCDF = 5438 – 3163 = 2275 lb/ft
53. 53
Calculate location of maximum moment,
y = -b+d+2*T/ = -2+8.7+2*2275/115 = 13 ft
Maximum moment,
Mmax = T y - (y+b-d)3
/6 = 2275*13 – 115*(13+2-8.7)3
/6 = 24770 lb-ft/ft
Required section modulus of sheet pile, S= Mmax/Fb = 22.47*12/32 = 8.4 in3
/ft
Use PDA 27 section modulus 10.7 in3
/ft
Design tie rod
Cross section of tie rod required, A = T*s/(0.6*Fy) = 2.275*12/(0.6*36) = 0.91 in2
.
Diameter of tie rod, d = 4*A/ = 1.08 in
Use 1-1/8” diameter tie rod.
Design soldier beam
Maximum moment in solider beam, Mmax = 0.1*T*s2
= 0.1*2275*122
= 32760 lb-ft
Required section modulus, S= Mmax/Fb= 32.76*12/(0.6*36) = 13.1 in3
.
Use W 8x18, section modulus S = 15.2 in3
.
54. 54
types of deep support systems
are commonly used in metropolitan cities.
(i) Diaphragm walls
(ii) Pile walls (Contiguous, Tangent or Secant)
(iii) Soldier pile w
ith wooden lagging walls
(iv) Sheet pile walls
(v) Composite supporting systems – that is, any of the retaining
systems
Retaining systems like
diaphragm wall, contiguous pile walls;
and soldier piles with wooden lagging
escribed in this article has been successfully used. Case studies of their use indicate that
adequate quality control measures and instrumentation monitoring of these systems go a
long way in ensuring their safeand economic deployment at sit
60. 60
Contiguous Pile Walls General – Piled Retaining Systems
Abstract
Providing space for parking, public amenities,etc in multi-storey buildings at
own centres has created a need to go deep excavationsinto ground. Deep excavations are
supported by systems like conventional retaining walls, sheet pile walls, braced walls,
diaphragm walls and pile walls. This article describes various excavation supporting
systems that are in vogue essentially contiguous pile wall and its advantages. A detailed
design methodology of an excavation supporting system is furnished in this study.
There are different types of pile walls
(Fig.4).Diameter and spacing of the piles is
decided based on soil type, ground water level and magnitude of design pressures.
Large spacing is avoided as it can result in caving of soil through gaps. In
iguous bored pile construction, center to center spacing of piles is kept slightly greater thanthe pile
diameter.
Secant bored pilesre formed by keeping this spacing of piles less
than the diameter.Tangen
61. 61
Fig. 4: Schematic Arrangement of Contiguous Piled Retaining System.
Contiguous piles serving as retaining walls
are popular since traditional piling equipments can be resorted for their construction. They are considered
more economical than diaphragm wall in small to medium scale excavations due to reduction in cost of site
operations. Common pile diameters adopted are 0.6, 0.8 and
1 .0m. These piles are connected with a Capping beams at the top, which assists equitable pressure
distributions in piles. These retaining piles are suitable in areas where water table is deep or where soil
permeability is low. However, some acceptable amount of water can be collected at the base and pumped
out.
ARRANGEMENT OF CONTIGUOUS PILe
64. 64
cant Pile Walls are formedby constructing intersecting piles. Secant bored pile walls
are formed by keeping spacing ofpiles lessthan diameter. Secant pile walls are used
tobuild cut off walls for the control of groundwater inflow and to
minimizemovement in weak and wet soils. Secant Wall constructed in the form of
hard/soft or hard/firm and Secant Wall Hard/hard wall. Secant Wall-hard- softs or
hard/firm is similar tothe contiguous bored pile wall
68. 68
Soldier Piles and Wooden Lagging supported system
The supporting system comprised soldier piles
ed at 1.8m c/c and with a closer spacing of 1.6m c/c near the launching shaft (Fig.8).
Wooden laggings of thickness 100mm to 120mm were supported between the soldier
piles.Three levels of Struts were provided at depths 3.285, 7.285, and 10.831m below the
established ground level (EGL-209.80m). Additional level of Waler beam with pre-stressed
rock anchors were provided 2m above the excavation level. Rock anchors with capacity of
86.4T,spaced at 3.6m c/c, were embedded 6m into the quartzitic bedrock to meet the
bond strength consideration