Micropiles from

• The piling solution for difficultground conditions

• Can be installed in confined spaces

• Caseless micropile with capacity inexcess of 3660 kN

Advantages overconventional piles

• Works in compression and tension

• Does not require temporary casing

• Improved mechanical ground/grout interactionreduces overall depth

• Dramatically increased production rates

• Lightweight rotary percussive drilling equipment

• Installed in confined spaces

• Permits top down jet grouting in saturated claysand silts complete with re-bar

• Perfect as pali radice for invisible structuralrepairs

• Bayonet fixing eliminates pile trimming andfacilitates remote de-coupling

• Self drilling micropiles provide a range ofworking loads from 110kN to 3,660 kN

• Minimal noise

• Low vibration

• Minimal spoil

2

Micropiles

Ischebeck Titan injection piles are ideal for use astension piles, mini piles and root piles (pali radice) inmicropiling situations.

Ischebeck Titan micropiles consist of a continuouslythreaded, hollow stem steel reinforcement tendoncombined with an OPC grout body of a minimum 25 N/mm2 strength. The profiled surface of the groutbody transfers tension and/or compression forcesinto the ground.

Ischebeck Titan micropiles comply with the newEuropean standard DIN EN 14199.

3

Micropiles

Coupling

Spacer

Coupling

Spacer

Titan hollow micropile

Grout cover > 25mm

Continuous drilling and grouting

Sacrificial drill bit

Flushing through hollow bar

4

Micropiles for basement construction

The Little Boltons

The owners of this exclusive propertydecided to build a new basement and totallyrebuild the interior of the existing structure.The new six metre deep basement wouldextend under the front and rear gardens aswell as beneath the house itself, a total areaof around 315m2.

The rebuilding of the interior required theremoval of all internal elements from groundfloor to roof level, including floors, ceilingsand stairs. Front, rear and side elevationswere retained and temporarily supportedduring construction.

Access to the site was only possible fromthe front of the property and so largeopenings were formed through the front andrear walls with sway frames being installed tofacilitate plant access.

Before demolition and constructioncommenced in earnest, Ischebeck Titanmicropiles with reinforced concrete pile capswere installed at the four corners and twosets in the centre of the property to supportthe sway frames. The piles were temporarilybraced at intervals as the basement’sexcavation progressed to assure stability ofthe support.

Zero piles were installed adjacent to party andgarden boundary walls.These were used toprovide temporary support to the existingretained structure and to provide lateralrestraint for the Ischebeck Titan micropiles.

Ground conditions comprised approximatelyfive metres of sandy silts overlying threemetres of medium-dense sandy gravelswhich, in turn, overlaid the London Clay.Ground water level was at approximately 6metres below existing ground level.

5

Micropiles for basement construction

Prior to excavation, and following asuccessful early testing programme toassure feasibility, Ischebeck Titan self-drillingmicropiles, designed to work in tension andcompression, were installed to enable thebasement floor to withstand gravitational anduplift forces.

In what was the first use of a bayonetcoupling in the UK, the micropiles wereinstalled from the original ground level, some6 metres above the intended finished depthof the basement.Rather than leaving the entire pile in place,as would be required using temporary casedpiles, the 6 metre drill string is uncoupled atthe bayonet fixing by simply reversing thedrilling direction, leaving the slab’s reinforcingmicropile in place at the 6 metre depth andbelow, but enabling the drill string to beremoved, and re-used, from the slab toground level.

This method of micropile installationdelivered huge benefits to both theexcavation and concrete substructureprogramme, and also for health and safetyissues. Other benefits include; no trimmingdown of the piles, no risk of pile damagefrom plant impact and no obstructions toexcavation plant. Lorry movements areminimal, which offers environmental benefits,as there is very limited spoil created duringinstallation and the cement grout is delivereddry and mixed on site. The method ofinstallation is very quick and was ideal forthese ground conditions, as conventionalpiles would have required temporary casing.

6

Micropiles for basement construction

Cruikshank Street

The construction of a 3.5m deep basementat a private residence in London made fulluse of Ischebeck Titan micropiles. Some150No. 6m long 73/45 micropiles wereinstalled using a cross-cut drill bit. Themicropiles formed an integral part of thesubstructure with the base and groundfloors.

• 150No. 6.5m 73/45 micropiles• 175mm cross-cut drill bit• Gravels over sand overlying stiff clay

Tregunter Road

Construction of a double basement to thefront and rear of the garden and under theexisting house. Ischebeck Titan micropileswere used as temporary works in two forms;Firstly for soil retention and then for supportto stabilise the sway frames to allow for plantaccess. Approximately 50No. 8m 127/111piles were installed using a 220mm drill bitfor the soil retention and 30No. 9m 40/20piles were installed for the sway frames.

• 40/20 and 127/111 micropiles installed intodense gravels

• Confined access• 127/111 tendon exposed and used as part

of permanent works

7

Micropiles for underpinning

Sellwood Terrace

Redevelopment and conversion of twoadjoining properties into a single prestigiousresidence.To accommodate a new basementthe end property had to be demolished andrebuilt, but this left the problem of excavatingthe 4.5m deep basement adjacent to theneighbouring property and garden/boundarywall on the other side.Traditionalunderpinning would have proved a costly andrisky operation and bored piling was ruled outas the client wanted to maximise thebasement’s footprint.

• 7.5m 127/111 micropiles installed• Piles installed both vertically and raked• Grout broken off front of piles to maximise

footprint

Arthur Road

Construction of basement to the rear ofgarden to accommodate a swimming pool.Ischebeck Titan micropiles were used astemporary works for soil retention as analternative to traditional underpinning.127/111 piles used in conjunction withtemporary 30/14 ground anchors installedunder the existing house. This eliminated theneed to prop internally, thus freeing upworkspace, allowing improvement on theprogramme. Approximately 40No. 9m127/111 piles were installed using a 220mmdrill bit for the soil retention and 20No. 9m30/14 ground anchors.

• 127/111 micropiles plus 30/14 groundanchors

• Quicker and safer than traditional methodsof soil retention

• Micropiles raked under the house tomaximise basement footprint

8

Arenas de Barcelona

This impressive project to create a newcommercial centre with underground parkingwithin the historic façade of Barcelona’s mainbullring admirably demonstrates the potentialof Ischebeck Titan micropiles. Consultationat the early stages of project design was thekey to its success..

In order to retain the original structure’simposing and symbolic façade, it wassupported by micropile columns installed atintervals around the structure. Parallel in-situconcrete beams were used inside andoutside to distribute the weight of thefreestanding façade. The interior of thestructure was removed and excavationcommenced to create the five levels ofunderground parking.

• 21m 73/53 Micropiles• Underpinning Roman bullring• Historic façade retained

Micropiles for underpinning

9

Micropiles for new build

Stratford Road

Private housing development to build eco-friendly home. Micropiles used to anchorhouse's split-level base slab. Total of 36No.vertical and raked 30/11 combi-coatedmicropiles installed through boulder clay andsandstone to 9m depth. Restricted accessrequired mini Marini Voyager drilling rig withMA100 rotary percussive head.

• Restricted access• Anchor split-level base slab• 30/11 combi-coated micropiles

Crossflats

Collapsed retaining wall very close to thewing wall of a house required stabilisation.A concrete block initially poured to preventfurther collapse of the road edge. Schemecombined 40/16 micro piles and 30/11 soilnails to stabilise road whilst spoil materialexcavated. Piles installed at 0.5m intervalsthrough concrete block to about 12m in theunderlying soft material and then intosandstone, creating contiguous piled wall.As spoil material excavated in front of verticalwall rows of soil nails were installed toprevent any lateral movement. Soil nailsinstalled to 9m into sandstone.

• Combined micropile/soil nail solution• 40/16 micropiles to 12m. 30/11 soil nails to

9m• Contiguous piled wall

Micropiles for new build foundations

Charlestown of Aberlour

Housing development constructed using mass concrete strip foundationsdirectly onto the rockhead. Area of the final two houses, however, hadapproximately 6m of fill overlying the rockhead, requiring an alternativesolution.

A working pile load of 170kN was established by the consulting engineersand a pile length of 7m was agreed. The micropiles were drilled throughthe overlying fill and 1m into the rockhead using a 70mm button typesacrificial drill bit.

26No. Ischebeck Titan 40/20 micropiles were installed in one 9-hour shift.

• 40/20 black micropiles• 170kN working load• 7m piles drilled through to rockhead

Broomhead Park

Private housing development comprisingtwo-storey flats of timber frame construction.Ground conditions of made ground and clayover sandstone dictated that foundations bestabilised. A total of 29No. 30/16 blackmicropiles installed to depth of 9m using95mm hardened clay drill bit. Piles used incompression to vertical load of 75kN.

• 30/16 black micropiles• Vertical pile load 75kN in compression• Made ground and clay over sandstone

Dufftown

Private housing development of fourteennew timber framed homes constructed onformer quarry site. Ground conditions of upto 15.5m of made ground on very stronglimestone demanded that foundations bestabilised. A total of 52No. 40/20 blackmicropiles installed to depths of 17m and10.5m using 70mm button drill bit. Piles usedin compression to vertical load of 170kN.

• 40/20 black micropiles• Vertical pile load 170kN in compression• Made ground on very strong limestone

10

11

Micropiles for tower bases

Micropiles for telecommunicationsmast foundations

Once permission has been granted for atelecommunication mast, it is important to get themast operational as soon as possible.

Typically 4No. 12m long Ischebeck Titan 40/20micropiles are installed to form part of the mast’sfoundation. This eliminates the need for a reinforcedconcrete base.

As there is a limited import of material, there isminimal disturbance to the surroundingenvironment.

The four micropiles are usually installed on themorning of day one. The increased production rateshelp to allow operational activity within three days ofentry to the site.

• Ideal for remote sites• Top detail of pile adapted to fit direct to cabin• Rapid production rates allow early operational

activity

Micropiles for tower cranebase

Demonstrating the versatility of theIschebeck Titan solution, this retailconstruction project utilised 40/16 micropilesto anchor the base of a tower crane onground consisting of clay overlying gravellyclay. The micropiles were installed as groupsof four in several locations throughout thedevelopment site.

• 40/16 micropiles• 150mm hardened clay drill bit• Clay overlying gravelly clay

12

Micropiles for gantry base foundations

Highway

MS4 signal gantry bases and foundations for signalupgrade on M40 between junctions 9 and 11.Ischebeck Titan provided micropile foundationswhere bases were situated over harder/rockymaterial which would prevent installation ofcontractor’s auger piles. Eleven bases installed,each with 8No. 10m long 40/16 micropiles withultimate load carrying capacity of 660kN. Drillmounted on excavator arm and drilled mostly fromhard shoulder which enabled crash barriers toremain in place. The work was successfully carriedout under a single lane closure and has led tofurther contracts.

• Motorway signal upgrade• 40/16 micropiles• Single lane closure

Rail

Approximately twenty GSRM bases have beenconstructed for Network Rail as part of theemergency communications network which allowsthe driver to talk to the control station. The baseshave been constructed using 40/20 micropiles to anaverage of 12m depending on underlying groundconditions. Each base has between 4No. and 8No.micro piles depending on size of the antennarequired.

• 40/20 micropiles• Network Rail communications antennae• Average 12m depth

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Micropiles in tension & compression

Project Omega

This scheme was part of a waste watertreatment works upgrade, which involvedinstalling tension micropiles through theconcrete slab of a new filter tank. They weredesigned as anti-flotation piles due to theproximity of the sea, with an ultimate load of900kN. A washer plate with a spherical collarnut above and below the plate was cast intothe slab. The 13m long 52/26 IschebeckTitan micropiles were installed through theoverlying clay into weathered sandstone.

• 115mm button type drill bit• 13m 52/26 black tension micropiles• 56No. permanent micropiles

Ormont

Project involved demolition of an existingbungalow and subsequent construction of amuch larger bungalow on same site. Part ofthe scheme involved the construction of alarge basement beneath the dwelling toaccommodate a gym and cinema. Some77No. micropiles were installed, working intension and compression to secure thereinforced basement floor slab. Workingloads of up to 450kN were required, usingdrill bit diameters of up to 280mm in theLondon Clay.

• Permanent works using black tendons• 40/16, 52/26 and 73/53 micropiles installed• Bearing plate with dual spherical collar nuts

cast into slab

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Drilled and pressure grouted micropiles

Titan micropiles are installed using a standard,rotary percussive drill rig in a one visit drillingoperation. The installation procedure uses a groutflush to stabilise the annulus, consequentlyeliminating the use of casings. This type ofinstallation is free from vibration and has a low noiselevel. Titan micropiles require smaller holes andwork with small rigs which means less drill spoil andlower mobilisation costs.

The grout body takes care of the radial friction in thesoil, the stiffness against buckling and the corrosionprotection. By using spacers (centralisers) at eachcoupler, a minimum grout cover of 20mm isachieved. The soil mechanics of the Titan micropiles,in comparison to standard reinforced concrete piles(DIN 4014), show very little settlement due to theirvery good soil friction (typical settlement less than5mm under design load). Due to excellentmechanical bond between the grout body and thesoil, the movement required to activate the friction isin the range of just a few millimetres.

The hollow steel section is far superior to a solidrod of the same cross section and steel quality withrespect to bending, shear and surface friction.

The material for the production of Titan micropiles isapproved micro alloy constructional steel.

In the thread production process, the materialstrength of the micro alloy steel is increased by coldforming without causing brittleness.

Titan micropiles comply with the European standardfor micropiles EN BS 14199.

As with reinforced concrete, these ribs induce anequal crack distribution in the grout. Excavated pilegrout bodies reinforced with Titan micropiles haveshown that up to 1.25 of the design load thecharacteristic crack widths are below the permissiblevalue of 0.1 mm as required for reinforcement .

This proves that the system complies with DIN 41289.2 and that single corrosion protection of minimum20 mm cover, as with reinforced concrete, issufficient.

Typical head detail

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Calculations for micropiles

Bond lengths for tension or tension andcompression piles

L = Tw x Fs� x D x Tult

Tw - Safe working loadFs - Factor of safetyπ - 3.142D - Drill bit diameter + enhancement factorTult - Skin friction

Example:

100kN tension load in sand with 110mm drill bit

100kN x 3� x (0.11 + 0.05) x 150kN/m

300.0075.41

3.97m long bond length

Please note that calculations may vary according todifferent national standards and regulations.

Compression only

Compression only piles have the ability to spreadthe load over the steel section and the grout bodyas a composite pile.

Load taken on grout (safe)

Area of grout x strength of grout4

40N/mm2 grout after 28 days

(Area of grout - Area of bar) x 40N/mm4

For 200mm drill bit - (No enhancement factor)

(2002 - 522 ) x π x 404 4

(40,000 - 2,704) x π x 104

= 293kN

Load taken on steel

Yield strength of steel2

Yield of 52/26 micropile is 730kN

7302

= 365kN

Total safe working load of pile in compression only

Load taken on grout + load taken on steel

293 + 365 = 658kN

To calculate load carrying capacity

The load bearing length, L, of the pile is determinedby grout body diameter, D, the ultimate soil friction,Tult, surface of the grout body and the safety factor.

End bearing capacity of Titan micropiles can beignored.

Skin friction values should be taken from siteinvestigations and tests.

Anchor/piletype

UnitTITAN30/16

TITAN30/14

TITAN30/11

TITAN40/20

TITAN40/16

TITAN52/26

TITAN73/56

TITAN73/53

TITAN73/45

TITAN73/35

TITAN103/78

TITAN103/51

TITAN127/111

Nominaloutside diam.

mm 30 30 30 40 40 52 73 73 73 73 103 103 127

Nominalinside diam.

mm 16 14 11 20 16 26 56 53 45 35 78 51 111

Ultimate load kN 245 275 320 540 660 925 1035 1160 1585 1865 2270 3660 2320

Yield point kN 190 220 260 425 525 730 830 970 1270 1430 1800 2670 2030

YieldstressT0,2

N/mm2 560 585 625 590 590 585 610 590 560 530 565 470 585

Cross section(A)

mm2 340 375 415 730 900 1250 1360 1615 2260 2710 3140 5680 3475

Weight kg/m 2.70 2.87 3.29 5.60 7.17 9.87 10.75 13.20 17.80 21.20 25.30 44.60 28.90

Threadleft/right hand

left left left left leftleft orright

right right right right right right right

Lengths m 3/4 3/4 2/3/4 3/4 2/3/4 3 6.25 3 3 4 3 3 3

Product Availability

Substantial stocks of equipment ensure ex-stockavailability across virtually all products. Nationalheadquarters are strategically located to achieve48-hour delivery on most items. Products areavailable for both hire and outright purchase.

Technical Support

Technical support is designed to maximise thebenefits of using Ischebeck Titan products in allareas of safety, productivity, economy andefficiency.

Advice is available at all stages of a project,including concept development, input onapplications, production rates, budget design,costings and on-site support. Guidance onindustry special European and nationalstandards is also available.

Since our policy is one of continuous improvement we reserve the right tochange without prior notice the specifications and methods of constructionmentioned in this document. No responsibility whatsoever can be accepted forany errors or omissions in, or misinterpretation of the contents. Products mustbe used in conformity with safe practices and applicable codes andregulations. Photos and details shown are for general guidance only and mayvary according to circumstances. For specific information refer to IschebeckTitan Limited. Copyright reserved.

Ischebeck Titan

Founded in Germany over 120 years ago,Ischebeck Titan is renowned internationally for itsaluminium formwork and false work, trenchsupport systems and ground engineering products.

Ischebeck Titan has introduced many innovationsto the world’s construction and civil engineeringindustries, creating a range of products whichenhance safety, productivity and efficiency on site.

Design excellence, precision engineering andquality materials ensure compliance with allrelevant performance standards.

Imported and Distributed in New Zealand by

ISCHEBECK NZ Ltd1 Wharangi StOnehunga 1061Auckland

PO Box 13613Onehunga 1643Auckland

T 09 6341973F 09 6345176E info@ischebecknz.co.nz