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 foundation is important for construction of foundation where bearing capacity of soil is poor. Pile foundation is use for distribution of uneven load of superstructure.There are so many type of pile are use for construction. Here i present some of pile with suitable condition for construction and methods for construction.
Thank you.
information on types of beams, different methods to calculate beam stress, design for shear, analysis for SRB flexure, design for flexure, Design procedure for doubly reinforced beam,
A foundation is the lowest part of the building structure. It is the engineering field of study devoted to the design of those structures which support other structures, most typically buildings, bridges or transportation infrastructure. It is at the periphery of Civil, Structural and Geo-technical Engineering disciplines and has distinct focus on soil-structure interaction.
Pile foundation is important for construction of foundation where bearing capacity of soil is poor. Pile foundation is use for distribution of uneven load of superstructure.There are so many type of pile are use for construction. Here i present some of pile with suitable condition for construction and methods for construction.
Thank you.
information on types of beams, different methods to calculate beam stress, design for shear, analysis for SRB flexure, design for flexure, Design procedure for doubly reinforced beam,
A foundation is the lowest part of the building structure. It is the engineering field of study devoted to the design of those structures which support other structures, most typically buildings, bridges or transportation infrastructure. It is at the periphery of Civil, Structural and Geo-technical Engineering disciplines and has distinct focus on soil-structure interaction.
Pile foundation are essential in case where SBC is low or the load coming from superstructure is too heavy,
Topics covered includes Materials used for making piles, Type of piles, load transfer mechanism, factors affecting selection of piles, Installation methods, load carrying capacity of piles, different load tests performed and the behavior of piles as a group.
Caissons_Advanced Construction Technology (Semester-6), Civil EngineeringA Makwana
It’s a prefabricated hollow box or cylinder.
It is sunk into the ground to some desired depth and then filled with concrete thus forming a foundation.
Most often used in the construction of bridge piers & other structures that require foundation beneath rivers & other bodies of water. This is because caissons can be floated to the job site and sunk into place.
Attributes affecting success of the residential projects – a reviewA Makwana
Construction industry is complex in nature and construction projects in India face many challenges and complex issues, such as time, cost, safety, quality and stakeholder satisfaction. According to Construction scenario there are various factors that affecting the residential project. These review paper shows the selection of criteria based on by giving the importance to other researcher’s research. The criteria were curtailed down according to literature review studied in this paper, interaction with stakeholder which are Engineers, Project managers, Architects, Consultants, Developers and educational experts, of Surat and Vadodara city in Gujarat.
A Review on Thin-shell Structures: Advances and TrendsA Makwana
This paper provides a review of research advances and trends in the area of thin shell structures. The art of building thin-shell structures has been with us since ancient times. In practical civil engineering, the necessity of covering large column free open areas with shell surfaces is often an issue. Over the course of time, this shell form became very popular to engineers due to a number of advantages it offers, and started drawing the attention of a number of researchers. A thin shell is a term not in itself as readily understandable by the layman as the terms dome or vault would be. It is in a sense a word coined on the basis of its structural connotations, as exhibited in the artifacts it creates. There are many interesting aspects of the use of shells in engineering, but one alone stands out as being of paramount importance: it is the structural aspect. At the beginning of this century, under the influence of the art movement and the dominance of industrialized building materials, any remnants of curvilinear architecture were mercilessly banished. Within that period avant-garde art emphatically proclaimed a total repudiation of the traditions and classical revivals that in architecture were symbolized mostly by arches and vaults. Ready-to-use rectilinear steel beams and columns and easy-to build rectilinear concrete forms struck a lethal blow to the curvilinear approach in architecture. Rectilinearity became synonymous with rationality, while curvilinearity came to symbolize decadence. Remember, for instance, the negative stigma given to the baroque for its assumed pomposity in glorifying curves. In practical terms such an attitude in design is clearly manifested in the present cityscapes that are totally free of arches, domes, shells, and any other form that is not rectilinear. With today‟s almost unlimited computer technology and the knowledge that can be gained from understanding the domes and vaults built both in the past and present, it is hoped that this research work on the review aspects of curvilinear forms will contribute to further exploration and encourage the application of thin shells by the engineers and architects to whom it is addressed. Masonry domes, concrete shells, and large steel contemporary domes are presented in historical terms as case studies and in conceptual terms from the architectural and structural point of view.
Soft Computing: Autoclaved Aerated Concrete Block using Chi-Square Test throu...A Makwana
Achieving an economy in Construction nowadays takes a lot of effort. Various researches are being made to improve the quality of Concrete block so that it can achieve high strength in low weight. One such product was invented known as an Autoclave Aerated Concrete (AAC) block. Autoclave Aerated Concrete (AAC) block is attributed with properties such as a load-bearing, lightweight, high-insulating, and durable. Autoclaved Aerated Concrete (AAC) block consists of basic materials that are widely available including Sand, Cement, Fly Ash, Lime, Gypsum, Aluminium Powder Paste, Water and an Expansion agent. The major volume in Autoclave Aerated Concrete (AAC) is covered by silica sand and it is one of the world’s most abundant natural resources. The finished product is up to five times the volume of the raw materials used, with an air content of 70% to 80% which makes them lightweight. The effort is made to fulfil the framed objective of this analytical research is to study, Engineer, Consultants and Trader’s perceptions towards the use of Autoclaved Aerated Concrete (AAC) block in construction projects and to analyse, the data collected as per questionnaire survey of targeted respondents study. This objective was achieved by a deriving conclusion about whether the AAC blocks are much better than clay bricks or not, by soft computing. The soft computing was done using one of the Statistical Packages for the Social Science (SPSS) method. i.e. Chi-square test. Required data for the study was collected through questionnaires that were distributed among the respondents who work at various construction projects. Mainly Engineers, Consultants, Traders and Contractors were selected as a respondent to getting efficient and reliable technical data. Result of the survey proved that the AAC block are better compare to the clay bricks.
Poster Presentation: An Integrated Approach for Enhancing Ready Mixed Concret...A Makwana
An Integrated Approach for Enhancing Ready Mixed Concrete utility using Analytic Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS)
FACTORS CONTRIBUTING TO THE RISING IMPORTANCE OF MODULAR CONSTRUCTION ADOPTIO...A Makwana
In recent times, the trend of modular construction adoption is increasing very fast due to
availability of latest tools and technology, efficient technical manpower and skilled labour
why mainly focus of this area is taken into
consideration through management approach with the help of Relative Importance Index
technique. Modular construction is one type of construction in which modular units are
produced in factory and then delivered to site and assembled as large volumetric
components. The modular units can be produced in any form; it may be service units such as
toilets, lifts, parts of rooms and complete rooms. The existing modular construction approach
is based on survey in Rajkot city. For survey work, Questionnaires is designed and distribute
to Consultants and Contractors. After data collection, rank has been given to the selected
factors of modular construction.
EXPANSION JOINT TREATMENT: MATERIAL & TECHNIQUESA Makwana
Although buildings are often constructed using flexible materials, roof and
structural expansion joints are required when plan dimensions are large. It is not possible to
state exact requirements relative to distances between expansion joints because of the many
variables involved, such as ambient temperatures during construction and the expected
temperature range during the life of a building. Expansion joints are periodic breaks in the
structure of the buildings. An expansion joint is a gap in the building structure provided by
an architect or engineer to allow for the movement of the building due to temperature
changes. An expansion joint is an assembly designed to safely absorb the heat-induced
expansion and contraction of various construction materials. They are commonly found
between sections of slabs, bridges, and other structures. The “assembly” can be as simple as
a caulked separation between two sections of the same materials. More recently, expansion
joints have been included in the design of, or added to existing, brick exterior walls for
similar purposes. In concrete and concrete block construction, the term applied is “control
joint,” but serves similar purposes. Throughout the year, building faces and concrete slabs
will expand and contract due to the warming and cooling of our planet through the seasons.
The structures would crack under the stress of thermal expansion and contraction if
expansion joint gaps were not built into the structures. Even today the expansion joint gaps
are often neglected during the design process, and simple caulking is used to fill these gaps
to complete a project. This simple caulking cannot handle the thermal expansion due to the
changing seasons, ultimately leaving a leak point in the structure. This expansion joint
becomes the main source of leakages in the structure which can ruin the interiors of the
building if not sealed or treated confidently. Waterproofing these joints often an overlooked
aspect of waterproofing design and detailing.
DEMOLITION OF BUILDINGS: INTEGRATED NOVEL APPROACHA Makwana
Every civil engineering structure is designed for a certain life period generally 100 years. After that the existence of a structure is very dangerous and unstable, which may cause a severe impact and be a cause of many deaths. So removal of such structures with proper safety measures has got great importance. Before any demolition of any type is employed in an area, it is vital that the rescue phase has ended completely. The rescue teams must have given clear information to the contractors that their rescue phase is finished in the selected area, since any demolition work carried out may reveal survivors. Such situations are highly sensitive and must be respected. A major disaster has an economic effect on the local region since the loss of buildings, lifelines and infrastructure results in a slump in the local economy. It is therefore important to boost the economy by employing as much local expertise and workforce as possible. This creates a unity in rehabilitation in the community and results in a more stable recovery. Due to this scenario, the demolition work should be carried out by a consortium, especially set up to do the work rather than commissioning the work to individual companies. This consortium must be set up in regions of high seismic risk to ensure rapid formation after a disaster. This will combat the eventual competitiveness of the large financial investors in the community which could result in a monopoly controlled by certain individuals. It would therefore be preferable to have a local demolition joint-venture to generate the needed local income after a disaster. There will, however, be a certain need for outside managerial and consultancy aid, especially in the developing countries, and this must be acknowledged and respected. The cooperation with the outside aid must be extensive and at a high level in conjunction with the local representatives so as to maintain as much of the local culture and style as possible. The outside consultants must be cautious when introducing major resources, such as machinery, into the post-disaster phases since this may be seen as taking work away from local resources.
ANTI-TERMITE TREATMENT: NEED OF CONSTRUCTION INDUSTRYA Makwana
Termites popularly known as white ants cause considerable damage to wood works,
furnishing etc. of buildings. The Latin name Isoptera means "equal wing" and refers to the
fact that the front set of wings on a reproductive termite is similar in size and shape to the hind
set. Termites are social and can form large nests or colonies, consisting of very different
looking individuals (castes). There are more than 2,500 different types of termites in the world.
In some country the loss caused due to termites is estimated to be as high as 10% of the capital
outlay of the building. Anti-termite treatment is therefore necessary so that damages are either
reduced or stopped together. Through regular inspections, a termite specialist can help
identify common hot spots for activity and warning signs for a termite infestation, plus share
tips to help keep termites at bay. Termites can fit through cracks as thin as an average business
card (1/32 inch) so proper maintenance is crucial to seal up any gaps around the foundation
and roof/eaves. To identify the termite and its uniqueness, the life cycle of termite is necessary
to understand. Anti- termites are used to combat the problem. There are combinations of
methods depending on what sort of damage is done by the termites. The treatment has to be
implemented at the time of construction for effective and permanent solution.
INTELLIGENT BUILDING NEW ERA OF TODAYS WORLDA Makwana
A building that uses both technology and process to create a facility that is safe,
healthy and comfortable and enables productivity and well-being of its occupants. With lots
of energy crisis in today‟s world now it‟s important for architects, engineers and construction
managers to make buildings which are energy efficient and intelligent by its functions and as
well as its usage, too. Technologies applied in intelligent buildings will improve the building
environment and functionality for occupants, while reducing operational costs. Smart or
clever buildings, perhaps focus on control systems, but intelligent buildings go far beyond
this. An intelligent building has an implicit logic that effectively evolves with changing user
requirements and technology, ensuring continued and improved intelligent operation,
maintenance and optimization. It exhibits key attributes of environmental sustainability to
benefit present and future generations. An intelligent building system concept recognizes that
the true cost of the building is not its cost of construction; it must include the operating and
maintenance costs over the structure‟s life span. Intelligent buildings yield cost reductions
over all these areas by optimizing energy use through automated control, communication and
management systems. They also guard against repair costs, employee time, productivity loss,
revenue loss and the loss of customers to competitors. Now a day, all heard of „sickbuilding‟
syndrome and the misery this can inflict in the workplace in terms of poor health
and lost production. The notion of the Intelligent Building is the modern civil engineer's Big
Idea in tackling these and other such deficiencies. The intelligent building can adapt itself to
maintain an optimized environment. An intelligent building must be smart enough to vary the
environment to suit the users and also to provide various means of communication or
network regardless of whether it is internal or external. At an even more fundamental level
intelligent buildings can cope with social and technological change and also are adaptable to
human needs. This paper provides a review of research era in the area of Intelligent Building
with case studies.
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.
Automobile Management System Project Report.pdfKamal Acharya
The proposed project is developed to manage the automobile in the automobile dealer company. The main module in this project is login, automobile management, customer management, sales, complaints and reports. The first module is the login. The automobile showroom owner should login to the project for usage. The username and password are verified and if it is correct, next form opens. If the username and password are not correct, it shows the error message.
When a customer search for a automobile, if the automobile is available, they will be taken to a page that shows the details of the automobile including automobile name, automobile ID, quantity, price etc. “Automobile Management System” is useful for maintaining automobiles, customers effectively and hence helps for establishing good relation between customer and automobile organization. It contains various customized modules for effectively maintaining automobiles and stock information accurately and safely.
When the automobile is sold to the customer, stock will be reduced automatically. When a new purchase is made, stock will be increased automatically. While selecting automobiles for sale, the proposed software will automatically check for total number of available stock of that particular item, if the total stock of that particular item is less than 5, software will notify the user to purchase the particular item.
Also when the user tries to sale items which are not in stock, the system will prompt the user that the stock is not enough. Customers of this system can search for a automobile; can purchase a automobile easily by selecting fast. On the other hand the stock of automobiles can be maintained perfectly by the automobile shop manager overcoming the drawbacks of existing system.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
2. PRESENTATION
OUTLINE…
• Introduction
• Uses of Piles
• Factors affecting selection of type of piles
• Types of Piles
• Pile Spacing
• Group of Piles
• Efficiency of Group of Piles
• Pile Cap and Pile shoe
Prof. Ashish Makwana 2
3. PRESENTATION
OUTLINE…
• Load tests on piles
• Pile driving
• Pulling of piles
• Loads on piles
• Causes of failure of piles
• Pile driving formulas
Prof. Ashish Makwana 3
4. INTRODUCTION
• When the depth of foundation is more than the
width of foundation then it is termed as deep
foundations.
• The deep foundations are classified as below :
– Pile foundations
– Cofferdams
– Caissons
Prof. Ashish Makwana 4
7. PILE FOUNDATION
• 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.
Prof. Ashish Makwana 7
8. Pile applications
Soft to
Firm Clay
Large Distributed
Weight
Very Large Concentrated
Weight
Strong Rock
Low
Weight
Prof. Ashish Makwana 8
9. USES OF PILES
• (i) Pile foundation is generally used, when simple
spread foundation at a suitable depth is not possible
either because the stratum of required bearing
capacity is at a greater depth or steep slopes are
encountered.
• (ii) In compressible soil or water-logged soil or soil of
made-up type, piles are used with advantage for
providing safe foundation for any type of structure.
• (iii) Piles are used for foundation for buildings,
trestles, bridges and water front installations (piers,
docks, etc.) Prof. Ashish Makwana 9
10. • (iv) The load coming from the structure is very heavy
and the distribution of load on soil is uneven.
• (v) They are also used in normal ground conditions
to resist heavy uplift forces or in poor soil conditions
to resist horizontal loads.
• (vi) The pumping of subsoil water is too costly for
keeping the foundation trench in dry condition.
• (vii) The timbering of excavations is too difficult to
maintain the sides of foundation trench.
Prof. Ashish Makwana 10
11. FACTORS AFFECTING SELECTION OF
TYPE OF PILES
Location & type of
structures
Ground conditions
Durability Cost consideration
Prof. Ashish Makwana 11
12. Factors affecting pile capacity
(cont’d)
Surrounding soil
Installation technique (like driven or bored).
Method of construction (like pre cast or cast in
situ)
Location of pile in a group
Spacing of piles in a group
Symmetry of the group
Shape of pile cap
Location of pile cap (like above soil or below soil)
Drainage condition in soil
Prof. Ashish Makwana 12
13. Classification of piles based on
function
End bearing pile Friction pile Compaction pile
Tension /
uplift pile
Anchor pile
Fender pile /
Dolphin
Sheet pile Better pile
Prof. Ashish Makwana 13
17. LOAD BEARING PILES
• The load bearing piles bear the load coming from
structure above. The load bearing piles may resist
the load by directly resting on the firm stratum or by
friction developed at their sides.
• The frictional resistance can be increased by taking
various measures, such as :
– (i) By increasing the diameter of the pile.
– (ii) By driving the pile to a greater depth.
– (iii) By making surface of the pile rough.
– (iv) By placing the piles closely.
– (v) By grouping the piles.
Prof. Ashish Makwana 17
18. Materials used in construction of
load bearing piles
SteelTimber
ConcreteTimber Steel H Composite
Pre-cast
Concrete
Concrete
1. Cast-iron piles 4. Steel piles
2. Cement-concrete piles 5. Timber piles
3. Sand piles 6. Wrought-iron piles
Steel Pipe
Prof. Ashish Makwana 18
19. 1. Cast-iron piles
• cast-iron piles: hollow
• Inside diameter of pile: 30 cm
• Thickness: 25 mm
• length of pile: 3 to 4 meters
• cast-iron: brittle, not possible to drive the piles into
the ground by means of a hammer
Prof. Ashish Makwana 19
21. 1.1 (a) Cased Cast-in-situ concrete piles:
– Raymond piles
– Mc-Arthur cased pile
– Union metal Monotube pile
– Sewage piles
– Western button bottom pile
1.1 Driven Piles
1. CAST-IN-SITU CONCRETE PILES
Prof. Ashish Makwana 21
22. Raymond piles
Mac-Arthur piles
• used primarily as friction
piles
• length of piles: 6 to 12 m
• diameter of piles: 40 to 60
cm. at the top & 20 to 30
cm. at the bottom
• Diameter: uniform
• Pile: uses an additional
steel casing of heavy
gauge
2 types:
- Raymond standard concrete pile
- Raymond step-taper concrete pile
Prof. Ashish Makwana 22
23. Monotube Piles
• Consists of tapered fluted steel shell without mandrel.
• Pile shells are driven to the required depth.
• Then interior of the shell is inspected.
• The shell is then filled with concrete.
• These piles are suitable for a wide variety of soil conditions
ranging from end-bearing to friction-load-carrying soils.
Prof. Ashish Makwana 23
24. Sewage piles
Button-bottom piles
• 1st: Thin steel shell is placed on a
precast concrete plug with steel core.
• 2nd: Steel pipe is driven over the plug.
• 3rd: Steel pipe is driven to a specified
depth.
• 4th: Steel shell has reached the desired
depth and then core is removed.
• Final: Steel pipe is filled with concrete.
conical shape
• 1st: Set up the steel pipe.
• 2nd: Steel pipe and button is driven
upto the required depth.
• 3rd: Corrugated steel shell is inserted
inside the steel pipe.
• Final: The steel pipe is withdrawn,
leaving the button (25 mm
diameter) in place and shell is filled
with concrete.
• Pile length: 23m, and load carrying capacity upto 50 tonnes
Prof. Ashish Makwana 24
25. 1.1 (b) Uncased cast-in-situ concrete piles:
• These piles are comparatively cheap, as no casing will
be left in the ground. But, great skill is required in
this case to achieve the desired results.
• The common types of uncased cast-in-situ concrete
piles are :
(i) Simplex piles (ii) Franki piles
(iii) Vibro piles (iv) Pedestal piles
Prof. Ashish Makwana 25
26. Simplex piles
• A steel tube is fitted with cast-iron shoe.
• Reinforcement is placed in the tube.
• Tube is slowly withdrawn after filling concrete.
cast-iron shoe
Prof. Ashish Makwana 26
27. Franki piles
• The pile has an enlarged base of mush-room shape, which
give the effect of a spread footing.
20 to
30 kN
• Franki pile diameter
is 50 to 60 cm while
enlarged base
diameter is 90 cm
• The pile has a
carrying capacity of
60 to 90 tonnes.
Prof. Ashish Makwana 27
28. Standard Vibro piles
Vibro-expanded piles
• Vibro piles is formed
by driving a steel tube
and a cast-iron shoe,
filling with concrete.
• Extracting the tube
using upward
extracting and
downward tamping
blows alternatively.
• Vibro-expanded piles: the
bearing capacity of soil is
increase by enlarging its
diameter at the bottom
• Dia. 35, 45, 50 cm
• Load 60 to 70 tonnes
• Length 25 m
cast-iron
shoe
Prof. Ashish Makwana 28
29. • In the first stage of
this pile, a casing tube
with a core is driven
upto required depth.
• In the second stage,
the core is withdrawn
and a layer of concrete
is deposited in the
casing.
• In the third stage, the
core is placed again in
the tube. The pressure
is applied on the
concrete through the
core and at the same
time, the casing is
withdrawn.
Pedestal piles
1st stage 2nd stage 3rd stage
Prof. Ashish Makwana 29
30. 1.2 Bored Piles
• Bored piles are those which are formed by forming a
bore hole in the ground and then concreting it, either with
the help of a casing tube or without a casing tube.
• Their procedure of construction is thus different than the
cast-in-situ driven pile where a heavy pile driving
equipment is required.
• These piles have advantage over the driven piles, in
those locations and those situations where the vibrations
and noise caused by driving of piles are to be avoided or
the strata of adequate bearing capacity is so deep that
they are difficult to reach by driven piles.
Prof. Ashish Makwana 30
31. 1.2 (a) PRESSURE PILES
1.2 Bored Piles
Pressure Piles
• Steel casing 1.2 to 1.8 m
long, 400 mm dia.
Prof. Ashish Makwana 31
32. • They are formed with the help of a casing tube, boring
auger and compressed air equipment.
• These piles are especially suitable for those congested
sites where heavy vibrations and noise are not
permissible, and also where heavy pile driving
machinery can not move in.
Procedure:
• 1. Steel casing is sunk in the ground, while a boring tool,
such as an auger, working inside it, excavates the soil.
• 2.Further section of steel casing are screwed
successively and sunk in the ground.
Prof. Ashish Makwana 32
33. • 3. A charge of concrete is placed in the tube, and the
upper end of the tube is closed with the help of pressure
cap. Compressed air is introduced through the air pipe of
the pressure cap, thus forcing the concrete down and out
against the surrounding soil. Simultaneously, the tube is
slowly extracted with the help of a winch.
• 4. Fresh charges of concrete are placed in the tube,
before the end of the tube comes above the previous
charge of concrete, and the process of compressed air
application is repeated, till the complete pile is cast and
tube is completely taken out.
• If it is required to increase the bearing value of the pile,
an enlarged base is formed by introducing cement grout
after the tube is sunk, and forcing is by air pressure into
the adjacent soil.
Prof. Ashish Makwana 33
34. • The under-reamed piles are provide an ideal solution
to foundations in black cotton soil.
• Diameter of an under-reamed piles: 20 cm. to 50 cm
• Diameter of the bulb 2 to 3 times the diameter of
pile.
• Under-reamed piles: reinforced with 10 to 12 mm.
dia. longitudinal bars and 6 mm. dia. of rings.
• A clear cover of 4 cm. is provided.
• The under-reamed piles are connected by a
reinforced concrete beam, known as capping beam.
1.2 (b) UNDER-REAMED PILES
Prof. Ashish Makwana 34
38. • Modification of under-reamed piles
• One type of cast-in-situ pile which combine the
advantages of both bored and driven pile
• Method of boring the piles and concreting the pile is
same as that for under-reamed pile, except that the
reinforcement cage is not placed in the bore hole before
concreting. After the concreting is over, the
reinforcement cage is driven through the freshly laid
concrete.
• Due to this feature, the compaction of surrounding soil
as well as concrete are effected and the load-carrying
capacity is increased by 1.5 to 2 times over normal
under-reamed piles.
• These piles are particularly suitable in loose to medium
dense sandy and silty strata.
BORED COMPACTION PILES
Prof. Ashish Makwana 38
39. Procedure:
• Prepare the bore hole with the help of spiral auger, using
guides, and then under-ream it with the help of under-reaming
tool. Concrete the pile, without placing the reinforcement
cage.
• Place of reinforcement cage, enclosing a hollow driving pipe,
on the top of freshly laid concrete. A cast iron conical shoe,
with a iron cleat welded to it, attached to the reinforcing cage.
• Drive the driving assembly through the freshly laid concrete to
the full depth by means of suitable drop weight (about 5kN),
operated with the help of mechanical winches. As the cage is
driven into the concrete, soil and concrete gets compacted.
This would result in increase in the diameter of the bore hole.
Extra concrete is simultaneously poured to keep it level with
the ground.
• After driving through the full depth of concrete, fill concrete in
the hollow drive pipe also. The pipe is then gradually
withdrawn leaving the cage and concrete behind.Prof. Ashish Makwana 39
40. Precast Concrete Piles
• Pre-cast pile: moulded in circular,
square, rectangular or octagonal
form
• Piles: cast and cured in casting
yard and then transported to the
site for driving
• size of the pile:
- diameter 30 to 50 cm.
- length may be 4.5 m. to 30 m.
• Steel bars: 20 to 40 mm
• 4 to 8 nos. with lateral ties of 5 to 10
mm wire spaced at 10 cm c/c for top
and Bottom 1 m length and 30 cm c/c
for middle length, concrete cover 50
mm
2. PRECAST CONCRETE PILES
Prof. Ashish Makwana 40
41. 3. Sand Piles
• Sand piles is spaced at 2 to 3
metres, usually under the
columns of the structure.
• A properly constructed sand pile
can take up a load of 100 tonnes
per sqmt. or more.
• Dimensions of sand pile is
determined from the load
coming upon it.
• Length: 12 times its diameter
Sand Piles
Prof. Ashish Makwana 41
42. 4. Steel Piles
H-beam Piles
Box Piles
Tube Piles
• H-beam piles: wide flange section
• Most common variety of steel piles in
general use
• Box piles: rectangular or octagonal in
shape
• Formed by suitable combinations of
steel sections.
• In this type of steel piles, the tubes
are driven into the ground.
• The pipes are driven either with
open end or with closed end.Prof. Ashish Makwana 42
43. 5. Timber Piles
Timber Piles
• Timber piles: prepared from
trunks of trees
• Common Indian timbers used for
piles: Babul, Chir, Deodar, Jarul,
Poon, Sal, Semul, Teak, White siris
and Khair
• Timber piles: circular or square
• Diameter of circular timber piles :
30 to 50 cm. and the side of a
square timber piles varies from 30
to 50 cm.
• Length of timber pile should not
exceed 20 times to its top width.
Prof. Ashish Makwana 43
44. 6. Wrought-iron piles
• These piles are generally made solid. The diameter varies
from 80 mm to 200 mm and the length is usually about 4
meters to 6 meters. The wrought-iron piles have suitable
devices for lengthening and sinking. These piles are mostly
used for shafts of screw piles.
• The wrought-iron piles are most suitable for use under sea
water. But as these piles are expensive, they are now replaced
by the steel piles.
Prof. Ashish Makwana 44
46. • This type of piles are used as separating members
below ground level and they are not generally
designed to take any vertical load. They are usually
sheet piles.
NON-LOAD BEARING PILES
Concrete sheet piles Steel sheet piles Timber sheet piles
Prof. Ashish Makwana 46
47. Pre-cast RCC sheet piles
1. Concrete sheet piles
• Piles: always pre-cast
• Reinforcement: provided as per design
• Piles: square or rectangular in cross-section
• Width of precast RCC piles : 50 to 60 cm.
• Thickness: 20 to 60 mm.
Prof. Ashish Makwana 47
48. 2. Steel sheet piles
Arch web steel sheet piles
Built-up type &
Corrugated steel sheet piles
• Offsets are provided in
the Centre so as increase
the moment of inertia
• Greater resistance to
bending
• Offer greater resistance
to bending
• Similar to arch web type
• Depth of offset:
increased considerably
• Offer greater stiffness
Deep arch web steel sheet pilesProf. Ashish Makwana 48
49. Straight web
steel sheet piles
Universal joist steel sheet piles
• Simplest form of steel sheet
pile
• Width: 40 to 50 cm.
• Thickness from 10 to 12 mm
• Piles: consists of I-
beams connected by
standard clutches
Z-type steel sheet piles
• Z-type steel sheet
piles: difficult to roll
and to drive
• Possesses highest
beam strength
• Used for heavy work
Prof. Ashish Makwana 49
50. 3. Timber sheet piles
Timber sheet piles
• Wooden sheet piles are commonly used for temporary works,
such as cofferdams.
• Wooden boards 80 – 150 mm thick, 200 – 300 mm wide, 2 – 4
m long Prof. Ashish Makwana 50
51. Butt joint
Built up tongue and
groove joint
Built up dovetail joint
VARIOUS JOINTS OF
TIMBER SHEET PILES
• Butt joint: formed by Placing
timber boards in a single line
• Used for shallow excavations
• Pieces of timber: attached
to wooden boards to form
tongues and grooves
• Practically no wastage of
timbers when this is adopted
• superior to ordinary
dovetail joint
Prof. Ashish Makwana 51
52. Ordinary dovetail joint
Lapped joint
Ploughed and
tongued joint
Splayed joint
• better than tongue and groove joint
• Adopted when wooden pile consists
of two boards
• better than tongue and groove joint
• Two boards are cut at ends in such
a way that when they are placed
together, a groove is formed.
• Requires more labour but it forms
an excellent joint
• Used for ordinary works
Prof. Ashish Makwana 52
53. Ordinary tongued and
grooved joint
Vee joint
Wakefield joint
• Used for work of superior
nature
• Used for ordinary works
• Used where more strength and
water tightness are required.
• Consists of three boards which
are bolted together
Prof. Ashish Makwana 53
54. Composite Piles
• Advantages:-
• Economical
• Easy to construct
• Suitable for ground conditions
in which other types of piles
will be unsuitable Prof. Ashish Makwana 54
55. Composite Piles
• A composite pile is formed when it is a combination either of a
bored pile and a driven pile or of driven piles of two different
materials.
• Process:
– A hollow steel tube is driven just below the lowest ground
water level.
– The tube is cleaned out.
– The timber pile is lowered into the steel tube and driven to
the required level.
– The tube is then filled with concrete and it is extracted by a
succession of upward extracting and downward tamping
blows.
Combination of materials:
wood and concrete
steel and concrete
Prof. Ashish Makwana 55
56. Screw Piles
Shaft Dia. 80-250 mm
Blade
Dia. 500-1500 mm
Screw pile with gimlet point
Screw pile with blunt point Screw pile with hollow conical point
Screw pile with serrated point
Prof. Ashish Makwana 56
57. Screw Piles
• A screw piles consists of a hollow cast-iron or steel cylinder
with one or more blades at the bottom.
• Types:
– Screw pile with blunt point
– Screw pile with gimlet point
– Screw pile with hollow conical point
– Screw pile with serrated point
• Situations when screw piles are used:
– To avoid shocks.
– To construct pile foundation of existing structures.
– To provide piles at places where it is not possible to install
heavy pile machinery.
– To provide foundations of marine structures, light bridges
etc.
Prof. Ashish Makwana 57
58. Disc pile
Disc Pile
• Disc Pile: A steel pile having a disk on its lower end to give
increased supporting power.Prof. Ashish Makwana 58
59. Disc Pile:
• Consists of hollow cast-iron pipe with a disc
• Diameter of the disc: 60 – 130 cm
• To facilitate jetting of harder strata and tough soils
• Discs supported by a number of radial ribs
• Piles most useful in subsoil consisting of sands / sandy
silt
• Most useful for marine structures
Prof. Ashish Makwana 59
60. PILE SPACING
• The spacing of pile is the center to center distance
between two piles.
• The factors to be considered while deciding the pile
spacing are as :
– The nature of soil through which the pile is driven
– The obstructions during pile driving
– The type of pile
– The depth of penetration
– The area of cross-section of the pile
– The center to center distance of piles in a group
– The manner in which the pile supports the load, i.e. whether the
pile acts as an end bearing pile or a friction pile or it acts both
ways
– The material of pile
– The damage to adjacent piles during pile driving operationProf. Ashish Makwana 60
61. PILE SPACING
Spacing criteria
- 2 times the diagonal dimension for square pile
- 2.5 times the diameter for circular or octagonal pile
Prof. Ashish Makwana 61
62. GROUP OF PILES
• The piles forming the group of piles may be arranged in
square, rectangular, triangular or circular as per the
requirement.
• In case of friction piles, the center to center distance
between successive piles should be 105 cm. or the
perimeter of the pile, whichever is greater.
• In case of end-bearing piles, the center to center
distance between successive piles should be 75 cm. or
twice the width of the pile, whichever is greater.
Prof. Ashish Makwana 62
65. EFFICIENCY OF GROUP OF PILES
• The efficiency of a pile group is taken as the ratio of the
average load per pile, when failure of the group occurs to
the load at failure of a comparable single pile.
• The efficiency of pile group depends upon the various
factors, such characteristics of pile (i.e. length, diameter,
material, etc.), space of pile, total number of piles in a
row and number of rows, etc.
• Two rules used to find out efficiency of group of piles:
– Converse Labbore equation
– Feld rule
Prof. Ashish Makwana 65
66. 1. Converse Labbore equation:
2. Feld rule:
• The efficiency of a single pile is 100%
• If piles are arranged in group, there is reduction of 6% in
efficiency for each direction.
• Overall efficiency of group of piles is obtained by dividing
total efficiency of all the piles with the total number of piles.
Prof. Ashish Makwana 66
67. PILE CAP AND PILE SHOES
Various types of piles
• When the RCC column or any load carrying structural
member is supported on more than one pile, the no. of
piles are connected through a pile cap to distribute the
load to the individual piles.
Prof. Ashish Makwana 67
68. Pile Cap and Pile Shoe
Square pile shoe Wedge-shaped pile shoe
Round pile shoe
Steel strap pile shoe for
timber piles
Closed-end shoe for
pipe piles
Socket type shoe for
timber piles
Prof. Ashish Makwana 68
69. Pile Cap
• Pile Cap should be extended beyond exterior piles by
10-15 cm.
• The pile should be embedded by at least 15 cm in the
pile cap.
• Reinforcement should be placed at least 10 cm above
pile head. Prof. Ashish Makwana 69
70. LOAD TESTS ON PILES
• The load tests on piles can be carried out by Pile load
method for determining the load carrying capacity of a
pile.
• The test load is applied with the help of a calibrated jack
plat; over a rigid circular or square plate, which may be
placed on the head of the pile projecting above ground
level. The reaction of the jack is borne by a truss or
platform, which may have gravity loading in the form of
sand bags, etc. or alternatively, the truss can be
anchored to the ground with the help of anchor piles.
• The load is applied in equal increments of about one-fifth
of the estimated allowable load. The settlements are
recorded with the help of three dial gauges of sensitivity
0.02 mm, symmetrically arranged over the test plate and
fixed to an independent datum bar.Prof. Ashish Makwana 70
71. • The test piles are loaded until ultimate load is reached.
Ordinarily, the test load is increased to a value 2.5 times
the estimated allowable load or to a load which causes a
settlement equal to one-tenth of the pile diameter,
whichever occurs earlier.
• The results are plotted in the form of load-settlement
curve. The ultimate load is clearly indicated by the load-
settlement curve approaching vertical.
• If the ultimate load cannot be obtained from the load
settlement curve, the allowable load is taken as follows :
– One-half to one-third the final load which causes settlement
equal to 10% of the pile diameter.
– Two-thirds of the final load which causes a total settlement of 12
mm or
– Two-thirds of final load which causes a net settlement (residual
settlement after the removal of load) of 6 mm.
Prof. Ashish Makwana 71
72. a) Jack loading: Reaction by loaded platform
Prof. Ashish Makwana 72
76. 1. Pile frames
• Mounted on standard tracked crane base machines for
mobility on land sites
• Light and easily transportable frames of tubular
construction
• All type of pile frames consists of leaders
• Ensure that the pile frame remains in its correct position
throughout the driving of a pile
Prof. Ashish Makwana 76
77. 2. Piling Winches
• Mounted on the base
• powered by steam, diesel or petrol engines or electric
motors
• Light winches: single drum, double and triple drum
winches
3. Helmet, driving cap, dolly and packing
• cast-steel helmet - placed over the top of a concrete pile,
to hold the dolly and packing
• Helmet should fit loosely around the pile.
• Dolly is placed in a square recess in the top of the
helmet.
Dollies are used for
- to moderate driving
- for hard driving a hard wood, such
as oak, green heart is usedProf. Ashish Makwana 77
79. Pile drive-cap / helmet
Hammer driving pile
• used to protect the heads of steel bearing piles
Prof. Ashish Makwana 79
80. 4. Jetting Piles
• water jetting - used to aid the penetration of a pile into a
sand / sandy gravel stratum
Pile with central jet pipe
Prof. Ashish Makwana 80
81. 5. Pile driving by Vibration
• Vibratory methods of driving sheet piles are best suited
to sand or gravel soil.
• Vibrators will drive steel piles through loose to medium
dense sands and gravels.
• Vibrators can also be used for extracting piles.
Prof. Ashish Makwana 81
82. various types of pile
hammers
Drop hammers
Single — acting
steam hammers
Double — acting
steam hammers
Diesel hammers
Hydraulically
operated hammers
6. Piling hammers
The function of a piling hammers is to impart energy required
to drive a pile.
Prof. Ashish Makwana 82
83. Variousfactors-
typeofpilehammers:
• Cost of purchase or hiring charges
• Available steam pressure
• Available head room
• Presence or absence of water
• Nature of work
• Material used for piles to driven
• Position of piles, i.e. vertical or inclined
Prof. Ashish Makwana 83
84. 1. Drop hammers:
- simplest form of hammer
Advantages:
(i) It is simple to operate.
(ii) Energy per blow can be varied by varying the height of
fall.
(iii) The initial cost is less.
Disadvantages:
(i) It is not easy to control the height of drop with any
accuracy.
(ii) There is danger that the operator will use too great a drop
when driving becomes difficult, it will increase the risk of
damage to the pile.
Prof. Ashish Makwana 84
85. Fig.23 Pile driving with Drop hammer
(a) Side elevation (b) Front elevation
Prof. Ashish Makwana 85
86. 2. Single-acting steam hammers :
– consists of a massive weight in the form of a cylinder
– steam or compressed air admitted to the cylinder raises it up
the fixed piston rod
– At the top of the stroke, the steam is cutoff and the cylinder
falls freely on to the pile helmet.
– height of drop: 1.37 m and rate of 60 stroke per minute
Advantages :
(i) If the height of drop is limited to 1.2 m., the damage to the
pile can be avoided.
(ii) A blow delivered by a heavy hammer with a short drop is
much more effective and much less damaging to the pile.
Disadvantages :
(i) The concrete piles are liable to be shattered by a blow from
too great a height.
(ii) Special care is needed, when seating a pile on to a hard
bearing stratum, such as rock.Prof. Ashish Makwana 86
87. 3. Double-acting steam hammers:
– used for sheet pile driving
– designed to import a rapid succession of blows to the pile
– rate of driving: 100 blows to 300 blows per minute
– mass of the ram: 2300 kg to 2700 kg. per blow
– driven by steam or compressed air
– drive under water to depths of 25 m.
Advantages :
• Pile frame is not required in this type of hammers. The
hammer is attached to the pile by leg-guides and a
timber framework is provided to guide the pile.
• It can be fitted with a chisel point for demolition and rock
breaking for extracting piling.
Disadvantages :
• Care is needed in their maintenance and lubrication and
during driving they must be kept in alignment with the
pile and prevented from bouncing.Prof. Ashish Makwana 87
88. 4. Diesel hammers :
– The diesel hammers provide an efficient means of pile driving
in favorable ground conditions.
– It consists of a cylinder, an impact block, a piston, a fuel-tank
and simple fuel injection system.
– In this type of hammer, the falling ram compresses the air in
the cylinder and the impact atomize a pool of diesel oil, which
ignites with the compressed air and the resulting explosion
imparts an additional kick to the pile.
Advantages :
– These hammers can be economical as they dispense with
steam or compressed air plant and are entirely self contained.
Disadvantages :
– Diesel hammers are ineffective in soft or yielding soils, when
the impact of the blow is insufficient.
– These hammers may also cause breakage of precast concrete
piles, while driving through soft ground.
Prof. Ashish Makwana 88
89. 5. Hydraulically operated hammers :
• This type of hammers produce less noise and vibration.
• The ram is raised by hydraulic fluid and it falls freely on
to the pile.
• The operation of the hammer is by a valve which allows
either single-stroke working by manual control or
automatic striking.
• The B.S.P. hydraulic hammers have a striking rate of 40
blow min. and ram weights in the range of 3 to 7 tonnes.
Prof. Ashish Makwana 89
90. PULLING OF PILES
The various reasons of pulling out of piles from their
positions are as follows :
(i) The piles are removed or pulled out, which are driven
temporarily, as in case of a cofferdam.
(ii) To replace the piles damaged during the driving
operations.
(iii) To prepare the data of the strata through which piles
are to be driven by carrying out pulling tests.
(iv) To reuse the existing piles, when the structure above
the pile is demolished or when the design of
arrangement of piles is changed.
Prof. Ashish Makwana 90
91. • The methods adopted for pulling of piles may depend upon
the equipment available, type of pile, etc.
• The concrete piles cannot be pulled successfully without
damage and therefore they cannot be reused.
• On the other hand, the steel piles can be pulled out without
damage and they can be reused at other places.
• The water jet or compressed air or a combination of both may
be adopted to reduce the skin friction during pulling
operations.
The methods adopted are as follows :
1. Use of double-acting steam hammers :
The double-acting steam hammers are worked in a reverse
manner. It becomes necessary to apply a steady pull of 4
tonnes per cm2. in this method of pulling the piles.
2. Use of vibrators :
The vibrators are employed to pull out the piles. Due to the
vibrations, the soil surrounding the piles becomes loose and it
facilitates the removal of the pile.Prof. Ashish Makwana 91
92. 3. Use of pile extractors :
– In this method, the specially designed pile extractors are
employed. The extractor can be put up into use immediately and
it does not require any special fitting.
4. Use of electricity :
– This method of pulling the piles is suitable for steel piles. A
direct current voltage is applied to steel pile for a short duration.
– The water present in the ground will be attracted towards the
surface of steel pile and thus it will lubricate the steel pile. The
skin friction will thus be reduced, resulting in easy removal of the
pile.
5. Use of tongs :
– The piles can be pulled by specially designed tongs. It is
suspended from a frame and with a pull of 50 tonnes or so, piles
can be pulled out.
Prof. Ashish Makwana 92
93. LOADS ON PILES
• While designing a pile, the loads to be taken into account are as
follows :
– The direct vertical load to be transmitted by the pile.
– The stresses developed during handling operations.
– The bending stresses developed due to eccentricity of loads
coming on the pile.
– The bending stresses developed due to curvature of the pile.
– The lateral forces due to wind, waves, currents of water, etc.
– The forces due to impact of ships, in case of marine
structures.
– The impact stresses developed during the process of pile
driving.
– The impact forces due to ice sheets or bergs.
– The forces due to uplift pressure, if any.
– The earthquake forces, etc.Prof. Ashish Makwana 93
94. CAUSES OF FAILURES OF PILES
The most common causes of failures of piles are as follows :
– The actual load coming on the pile may be more than
the designed load.
– The bad workmanship in case of cast-in-situ cement
concrete piles.
– The attack by insects, etc. on wooden piles, causing
the decay of timber piles.
– The breakage due to overdriving especially in case of
timber piles.
– The damage due to abrasion resulting from the
absence suitable protective covering.
Prof. Ashish Makwana 94
95. – The buckling of piles due to removal of side support,
inadequate lateral support, etc.
– The absence of statistical data regarding the nature of
strata through which piles are to be driven.
– The improper classification of soils.
– The improper choice of the type of pile.
– The improper choice of the method of driving the pile.
– The presence of soft strata just below the tips of piles.
– The lateral forces not being taken into the design of
the pile.
– The wrongful use of pile formula for determining its
load bearing capacity.
– The mis-interpretation of the results obtained during
test loads.
Prof. Ashish Makwana 95
96. PILE DRIVING FORMULAS
1. Dynamic formulae :
– These are used for precast concrete piles. When a pile-
hammer hits the pile, the total driving energy is equal to
the weight of hammer times the height of stroke.
– In case of double acting hammers, some energy is also
imparted by the steam pressure during the return stroke.
– The total downward energy is consumed by the work
done in penetrating the pile and by certain losses. The
various dynamic formulae are essentially based on this
assumption. It is also assumed that soil resistance to
dynamic penetration of pile is the same as the
penetration of pile under static loading.
Prof. Ashish Makwana 96
97. The following are some of the commonly used dynamic formulae.
(a) Engineering New Formula :
• The Engineering News Formula was proposed by AM
Wellington (1818) in the following general form :
Prof. Ashish Makwana 97
98. The above formula reduces to the following forms :
(i) For Drop Hammers :
(ii) Single-acting steam Hammers:
(iii) Double-acting steam Hammers:
where, a = effective area of piston (cm2)
p = mean effective steam pressure (kg/cm2)
Prof. Ashish Makwana 98
99. (b) Hiley's Formula (IS Formula) :
• Indian Standard IS : 2911 (Part-I) 1964 gives the
following formula based on original expression by Hiley :
Prof. Ashish Makwana 99
101. 2. Static Formulae
• The static formulae are based on the assumption that the
ultimate bearing capacity Qf of a pile is the sum of the total
ultimate skin friction Rf and total ultimate point or end bearing
resistance Rp.
• As = surface area of pile upon which the skin friction acts
• Ap = area of cross-section of the pile on which bearing
resistance acts
• For tappered piles, Ap may be taken as the cross-sectional
area at the lower one-third of the embedded length
• rf = average unit skin friction, which may be taken equal to
unit cohesion for cohesive soils
• rp = toe resistance
Prof. Ashish Makwana 101