7 2 ok CW2C DRIVEN PILE

Welding machine set 04After fabrication of RC pile at yard and approval from Engineer, the driving pile construction flow chart is as below: Mobilization of driving equipments to site De

CONSTRUCTION METHOD OF

DRIVEN RC PILE

TABLE OF CONTENTS

I SITE ORGANIZATION CHART

II MAIN EQUIPMENT

III CONSTRUCTION FLOW CHART

IV CONSTRUCTION METHOD

I SITE ORGANIZATION CHART

The site organization chart is shown as below

II MAIN EQUIPMENT

Equipment

Description Specificatio n Unit Quantit y

Driven hammer 4.5 ton ea 01 Driven hammer 3.5 ton ea 01 Crawler crane 40~60 ton ea 02 Hydraulic Crane 30 ton ea 02

Safety Manager Project Manager

Deputy Project Manager Construction Manager

Quality Manager Site Manager

Surveyor Site Engineer

Driven Pile Construction

Team

Welding machine set 04

After fabrication of RC pile at yard and approval from Engineer, the driving pile construction flow chart is as below:

Mobilization of driving equipments to site Delivery of RC piles to site

Setting out precise location of piles by total station

1 Driving piles

2 Pile rest (about 6 days)

3 Re-driving pile to decide refusal of pile

Decide the length of pile

IV CONSTRUCTION METHOD

1 Preparation work

Prior to the commencement of the driving pile works, the site area will

be cleaned The access road will be prepared to support the work of mobilization of pile and equipment

2 Mobilization

Equipment will be mobilized by the road way and water way into construction area and temporary road

3 Fabrication and delivery of piles

RC piles will be fabricated in casting yards near construction areas Piles are not lifted or transported until the grade of concrete is reached 100% compressive strength So, the Contractor has to use admixtures in order

to reach 100% compressive strength within 7 days from the time of casting if it had been approved by the Engineer

4 Driving platform

Before commencement of driving work, driving platform will be executed

by filling sand It will be leveled and compacted to ensure that driving machine can work safely

5 Setting out

The setting out for the piles is to be completed prior to commencement

of driving All main setting out points are to be maintained safe and undisturbed until the work is completed

A temporary benchmark will be defined at the strong foundation Total station will be used to set out location of the piles

For vertical piles, move driving machine to correct coordinate of each pile, use total station to check straightness and drive piles

For inclined piles, calculate elevation, dimension, sloped angle And then, move driving machine to locate position and drive piles

6 Selection of hammer

Hammers are selected base on:

Kind of hammer: Diesel – single acting steam

Dimension of Piles

Length of pile

Required pile capacity

Driving hammer will be used as below:

Piles 45x45 cm: selecting driving hammer of 4.5 ton

Piles 30x30 cm: selecting driving hammer of 3.5 ton

7 Controlling groundwater

Driving works will be done on land, if ground level is higher than groundwater level about 0.5 to 1 m, driving works is possible

Water pump will be used to control groundwater

8 Controlling ground

Ground vibration: Driven piles will be worked on empty ground and soft soils where do not affect to any structures Water glass method will be used for visual of vibration

Ground movement: Piles will be driven that follow best sequence, this sequence is shown in attach drawing

Avoiding damage to adjacent piles: All piles will be driven in underground After finishing driving each pile, fill pile hole and driving next piles

9 Pile splicing

The splice joint will be using connecting box

Install splicing box in accordance with the design drawing End of two segments must be in full contact and with the same center line thru hole with guiding rod at the center of two connecting pile In order to assure good contact of two segments, the upper pile segment will be press with 10 – 15

% of the design load And if not in full contact and will have gap or clearance

in one side of the two segments, it will be filled with filler plate that is equal

or depending to the size of gap or clearance and weld to each end of the two connecting segments After setting two segments in the same center line and welding completed as well as painting of Bitumen in 2mm Driving

of pile continue

10 Driving RC pile

10.1 Preparation for driving pile

Prior the commencement, the working drawing will be submitted and approved by the Engineer

Bassically, Follower will not be used But depending on the actual condition in the Site, the contractor will pick up suitable driving method Placing a wood cushion on pile top to absorb shock in order to prevent broken pile head and reduce noise during driving Before starting R.C pile driving, certificate of crane and hammer will be checked

10.2 Handling, pitching

Handling

Piles will be lifted up by crane at lifting hook and chocking at 2 position for each pile (2 lifting hook position shown on the drawings) by wooden

on Barge After that piles come to the site, it will be lifted by crane After driving piles to design elevation, piles will be rest (about 6 days), re-driving to decide actual refusal, RC pile length will be decided

Pitching

Pile will be pitched accurately at all positions and driven to the instructions on the Drawings or the Engineer’s decision Piles deflected from the vertical or proper line will, where order by Engineer, be withdrawn and re-pitched until the correction of the position or line of

any pile is permitted Any pile damaged by reason of improper driving or driven out of its proper location or driven below the elevation fixed by Drawing or the Engineer, will be corrected

The pile will be withdrawn and replace by other longer pile if necessary Any holes created from the withdraw piles will be packed with approved non-plastic material before re-driving takes place, or a second pile will

be driven adjacent to the defective

All inclined piles made by driving machine or by any causes will be withdrawn and driven again

10.3 Determination of bearing capacity

2

P

S 0.1

E



 for all other hammers(P: posunds;E: foot/pounds;S: inches)

Where :

P = bearing capacity in pounds

W = weight , in pounds ,of striking parts of the hammer

H = height of fall in foot

E = energy produced by the hammer per blow in foot/pounds.Value based on actual hammer stroke or bounce chamber pressure observed (double acting diesel hammer )

S = the average penetration in inches per blow for the last 5 to 10 blows for gravity hammers and the last 10 to 20 blows for all other hammers The above formulas are applicable only when:

The hammer has a free fall (gravity and single - acting hammers only ) The head of the pile is not broomed , crushed ,or otherwise damaged The penetration per blow may be measured either during initial driving

or by redriving with a warm hammer operated at full energy after a pile set period,as determined by the Engineer

In case water jets are used in connection with the driing ,the bearing capacity will be determined by the above formulas from the results of driving after the jets have been withdrawn

10.4 Driving

Use crane to lift and move RC pile, adjust pile position in accordance to design, arrange two steel angles L75x75x10 at the two sides of the pile

to keep and guide the pile during driving works

Piles will be supported in line and position with leads while driving Pile drive leads will be constructed so as to afford free movement between pile and hammer, and they will be held firmly in position to ensure rigid lateral support to the pile during driving Except where piles are driven underwater, the lead will be sufficient length to make the use of a follower unnecessary, and will be designed to permit the proper placing

of batter pile when driving pile will start

After delivery piles, pile markings are required at every 500 mm to check length and for blow count as shown in below

Checking the penetration of pile during driving Stop driving in case of sudden stand or fast penetration and find solution for the case

Driving in very hard soil base, in this case Pre-Boring will be selected

Pre-Boring method: Pre –Boring method at pile location will be followed

to facilitate the driving pile The depth of hole must be terminate at elevation 1.5m above design elevation of pile toe After boring work had finished, pile will be place in to the hole and drive with hammer to design length

Driving in extremely soft soil

Pile will be anchored to slide lead guide of hammer by cable to prevent initial slip of pile from slide lead guide

Install hammer with smaller energy than actual hammer (Hammer with preferable energy to driving pile to design load) on pile cap Let the pile penetrated into the soft soil layer by self-weight of pile and small hammer When the pile can not penetrated into the soil base, install the actual hammer on pile cap and continue driving pile to obtain the design length

Maintaining pile alignment:

Pile will be kept in right position During driving pile, pile will be maintained vertical by plumb bob by two directions Plumb bob is hang

up simple system steel frame and is placed out of pile from 3-5m Piles deflected from vertical will be adjusted immediately

The top elevation of RC piles is lower than the existing elevation of platform Thus, using the dolly pile when driving normal piles, for test piles, RC pile will be extended over platform elevation

The driving machine is automotive machine; it can change the angle of gradient of pile but do not use instruction frame

Cushion is made by timber or cement packet if necessary, checking pile head during driving time and prepare the sufficient cushions

10.5 Record driving information

In the beginning driving state:

For single acting air hammer: Record number of impulse and drop height

of impulse part of hammer when pile penetrated each of 1m soil

For Diesel hammer and double acting air hammer: Record number of impulse and times of driving when pile penetrated each of 1m soil

When the driving close to design refusal value:

For Diesel hammer and double acting air hammer: Record number of refusal and pile penetration for every minutes

Besides, pile numbers, positions, types, sizes, actual lengths, dates driven, lengths in footings, penetration under final blows of the hammer, striking energy of the hammer, length cut off, and final pay lengths we will keep the record also

All the necessary information will be shown in the driving record and submitted to Engineer

10.6 Driving criteria to terminate

Define the refusal

Record the number of hammer blow for each meter of pile that penetrates into foundation when driving and record the total blow For last meters, record the number of blow for each 10cm of pile Driving pile to the design elevation

Stand by the pile driving:

+ 3 days when driving in sand or clay sand

+ 6 days when driving in clay or clay loam or other soil

Continue driving 45 blows, in which 10-15 first blows is beginning stage, the refusal will be determined by average value of last 30 blows

For the piles that driving to the design elevation but not yet meet the required refusal, waiting for 12-24 hours and continue driving until reach the calculated refusal

For the piles that not yet drove to the designed elevation but the refusal have already meet for over 10 blows, stop driving The continuous driving will be approved by the Engineer

Condition to terminate the test pile

Pile reaches the design refusal The penetration must satisfy the formula as mentioned above

In case the test pile does not reach the design refusal, inform the involve

parties to solve each other

Figure of getting data for pile refusal

11 Cut of

All RC piles are cut off as indicated on the Drawings or as directed by the Engineer at elevation that the reinforcement will extend into and connect with the cap or footing

12 TEST PILE

According to drawings and carry out driving test pile for final decision on permanent pile length

13 QUALITY CONTROL

All the works will be carried out following the established Project Quality Control Plan

Sequence of acceptance the quality of piles :

Piles at the site: acceptance piles and document of piles

Setting out centerline of lines: Using total station

Mobilizing equipment: checking equipment certificates

Driving piles: Using theodolite for checking vertical direction and incline angle before driving piles

Conditions for termination driving piles:

Driving piles to designed elevation and refusal confirm to calculation Sufficient acceptance documents and site documents

Cases of termination of driving pile:

Driving piles to elevation is higher than designed elevation but that pile cannot drive down or refusal is smaller than calculation that can cause breaking piles

Driving piles to designed elevation and refusal is bigger than calculation

Marking site reports have signature of the Engineer and displaying sequence of driving pile After that, submitting to authority to check and have opinion about it

Pile driving records:

Records of pile driving will be submitted to the Engineer within two day after each driven pile Form of pile driving records see attached files

General

All of workers should put on their safe shoes, helmet, and leggings Welding worker have specialize mask, gloves, gearing and other working wears

Before starting the works, operators and labors should memorize the method, contents, scope of work through the training

Labors must keep out of the safety radius for piling rig

The team will be mixed experts with beginners

The condition of climate such as temperature, rainfall etc., will be recorded, researched The Contractor will look for the countermeasure of the climate Installation of safe passageway for labors to move in excavated places

Labor will be reminded about the communication, signal when emergency occur

Whenever team work, to make sure the scope of work and working conditions

on site

To check the excavation depth, slope compare with Drawings

To reinforce or replace the damaged facilities before starting the work

Do not place the heavy equipments near the edge of higher place.

Checking the water flow line such as river and stream, to prevent the flood water from inflow in the working area

To use the equipment in stable capacity

During the operation of heavy equipment, prohibit the workers to come into the working area

When more than one equipment operates in working area, should keep the working space against each equipment

To observe and check the earth deflection in shape

Wear life jacket when working on river

15 Safety management plan

Daily Check 1 time/day Safety Engineer, SiteEngineer Site inspection Weekly Check 1time/week Safety Engineer, SiteEngineer Site inspection

Prior and during the construction, basic safety precautions will be implemented to work efficiently and to prevent any accident or casualties

During the process of construction, installation, the Contractor’s construction teams in the site will be:

Not to cause pollution exceed the permissible limit for the environment surrounding the site:

Discharge harmful elements such as dust, toxic gas, noise etc.; Discharge water, mud, wasted materials, soil, sand in the population area, roads, ponds and lakes, planting field surrounding the site that cause bad impact on life and production of the resident near construction site

Not to cause danger for the population living surrounding the site

Not to cause sagging, sliding, cracks, collapse for the surrounding houses, buildings and technical infrastructure (cable system, underground pipeline, sewer, ditches…)

Not to cause obstructing to traffic activities by encroaching roadway, sidewalk

Not to let happen events of fire, explosion

After construction completion, all construction equipment must put the site in order, neat and clean; remove all excess materials, demolish temporary facilities, repair damaged parts of surrounding road, sidewalk, sewer and trench, technical infrastructure, houses and buildings etc caused by the construction process strictly in accordance with initial agreement or current regulations issued by the Government The best