Embed Size (px)
Citation preview
BAUERMixed-in-Place
Bauer Mixed-in-Place (MIP®)a resource-effi cient, environmentally compatible and productive construction method
of Mixed-in-Place walls have been constructed to date.
The Mixed-in-Place drilling rigs manufactured by Bauer can be deployed in the most confined urban construction sites as well as in the largest dams and dikes.
Comprehensive quality assurance measures in each phase of preparation, implementation and follow-up guarantee construction activities that are executed reliably and on schedule.
The patented Bauer Mixed-in-Place method (MIP®) has been successfully implemented for over 25 years for the construction of excavation pit enclosures, for foundation work and for flood protection.
The key feature of this method involves mixing the existing soil in-situ with a binding agent. The experience amassed by our highly-qualified team as well as the continuous development of our drilling and mixing rigs allows us to carry out the Mixed-in-Place method in virtually any soil formation. Well over 2 million m²
Over 25 years of Mixed-in-Place .......................4 Competences• Soil mixing is a question of experience .............5• The method ......................................................6• Equipment ........................................................7
Quality and HSE .................................................8
Areas of application• Dams and dikes .............................................. 10• Excavation pit enclosures ............................... 16• Ground improvement ...................................... 22
Contents
Over 25 years of Mixed-in-Place
1988 First application: Nuremberg, the “Germanisches National- museum“ MIP test piles and MIP pile bores for soldier pile wall
1990 Nuremberg “Krokodil“: Bored pile wall with Mixed-in-Place method, Start of development of the triple auger
1992 Bauer patent “Method for the production of soil mortar columns“
Nuremberg, InterCityHotel: First application of the triple auger with an auger diameter of 370 mm and a drilling depth of 9 m
2009 Introduction of the verticality measurement system for MIP 370 mm
2010 Initial usage of auger intermediate guiding with MIP 550 mm
2011 Introduction of remote data transmission
2013 Installation of geothermal probes in Mixed-in-Place walls
2015 Commissioning of the latest RG 25 series with a drilling depth of 21.50 m
2016 Trench position detection using GPS
Since 1996, the Bauer Mixed-in-Place method has also been applied outside of Germany. First in neighboring European countries, and later in the Near East, Middle East and Far East as well as in North America.
1994 Oberaudorf on the Ebbs in Austria: First Mixed-in-Place permanent cut-off wall
1995 Commissioning of the Bauer RG 20 pile driving rig with an auger diameter of 550 mm and drilling depth of up to 17 m
2002 Approval for the Mixed-in-Place method by the construction supervisory authority, “Institut für Bautechnik“ in Berlin
Karlsfeld near Munich: Mixed-in-Place wall with BG 42, auger diameter of 880 mm and wall depth of 24 m 2004 Martinsberg School Complex in Baden near Zurich: Largest excavation depth of a Mixed-in-Place pit at 13.90 m 2005 Passau-Haibach, sewage treatment plant: First application of lattice girders as reinforcement 2006 Offenbach, Lang tar factory: Mixed-in-Place for a funnel and gate system 2007 Salzwedel, trough for undercutting of the B 71: Mixed-in- Place wall combined with underwater concrete slabs
4 25 years of Mixed-in-Place
5Competences
Soil mixing is a question of experience
this extensive expertise has been pooled in a dedicated specialist department. Well-trained teams and high-tech equipment guarantee the application of the Mixed-in-Place method in virtually any soil formation.
The engineers of Bauer Spezialtiefbau can draw on years of experience. Since the start of the 1990s, over 500 construction sites with more than 2,000,000 m² of Mixed-in-Place walls have been realized. Since 1994,
– By using the triple auger featured with continuous flights heteroge-neous, layered soil structures are homogenized.
– Using the existing in-situ soil as building material/aggregate conserves resources.
– The low-vibration wall const-ruction technique using rotary drilling reduces the strain placed on local residents, sensitive neigh-boring buildings and on previously damaged dams and dikes.
– The high productivity of the MIP method leads to short construction periods.
– The Mixed-in-Place method is highly attractive particularly in economical and ecological terms, as it generates less noise and fewer exhaust gases. (see below)
– Product quality is ensured by comprehensive preparatory and construction phase measures.
– The mix design can be chan-ged on the construction site at any time. This allows the slurry to be adjusted to the actual soil conditions.
– Mixed-in-Place is generally more affordable than conventi-onal cut-off wall methods.
– High flexibility concerning possible adjustments as the complete MIP technique, drilling rigs, mixing plants, are develo-ped and constructed by Bauer.
Advantages of the Mixed-in-Place method
Drill spoil removal ... from the construction site
Supply of concrete, cement and bentonite... to the construction site
MIP walls
Pile walls
A comparison of transport volumes between MIP walls and pile walls very clearly demonstrates the economical and ecological benefits
Mixed-in-Place
“Mixed-in-Place“ refers to mixing the existing soil in-situ with a binding agent. A triple auger is used to break up the soil and work in the binder slurry.
The triple auger is drilled down to final depth with slurry being added. During the subsequent homogenization process, the direction of rotation of the individual augers is varied so that a circular material flow is produced in the trench.
This vertical material flow is only made possible through the use of augers with continuous flights, which ensures the homogeneity of the soil binder and thus of the finished wall.
“Soil mortar“ conserves resources
The method Trench cutting
“Double pilgrim step“ production sequence:
Primary cut
Primary cut
Secondary cut
Additional cut
Additional cut
Primary cut
To ensure that a solid, seamless wall is produced, MIP walls are constructed by the double pilgrim step method. This patented construction method is characterized by additional processing of the overlapping areas comprising primary and secondary panels.
This guarantees that the triple auger pene-trates and processes each wall element at least twice.
Work sequence
7Competences
Mixed-in-Place
Equipment
RG 14 T RG 16 T RG 19 T RG 25 S
RG 14 T RG 16 T RG 19 T RG 25 S
Auger diameter (mm) 370 370 370 550
Max. drilling depth (m) 10.50 11.50 13.50 21.50
Crawler width (m) 4.20 4.20 4,50 4,60
Operating weight (t) 52 60 75 136
Engine power (kW) 313 470 563 563
Rotary drive KDK 14 KDK 14 / KDK 21 KDK 21 KDK 70
8 Quality and HSE
Quality and HSETo ensure the characteristics required of the Mixed-in-Place elements or walls, comprehensive monitoring is conducted of the building materials used, their fabrication and the construction process.
The production data is recorded in the Mixed-in-Place drilling rig using the Bauer B-Tronic data acquisition system. The data is displayed and archived with the B-Report analysis software.
Essential production parameters such as drilling depth, slurry flow rate, oil pressures and the number of drilling tool revolutions as well as the verticality of the triple auger are continuously displayed and recorded for the rig operator.
Production data monitoring and collection
Knowing the verticality of individual panels or wall sec-tions is essential for constructing deep cut-off walls and retaining walls. For many years, several Mixed-in-Place drilling rigs and their drilling tools have been equipped with a inclination measuring system.
After reaching the final depth, the verticality of the triple auger is measured and displayed online for the rig oper-ator. This means that any finishing work can carried out immediately.
Verticality measurement
Suitability tests are conducted before beginning the installation in order to determine the composition of the binder slurry as well as the quantities required for installation. In the laboratory, different binder recipes are mixed with soil probes taken on-site and the char-acteristics of the hardened Mixed-in-Place material are tested.
Suitability testing
Detection of position dataSince the end of 2015, the first Mixed-in-Place drilling rig has been equipped with highly precise positioning detection. To achieve the best possible reception con- ditions, the two GPS antennas are mounted on the
top of the leader rig. In combination with the inclination sensors in the leader rig and in the triple auger, the posi-tion data for each panel is determined and recorded.
9Quality and HSE
Mixed-in-Place drilling rigs are equipped with a module for remote data transmission. This allows device and pro-duction data to be retrieved from any location. Because of the online monitoring option on the rig operator‘s work screen, direct consultation with off-site experts is possible for any deviations that may arise.
Remote data transmission
Evaluation of the production data is carried out using B-Report. A production report is created for every panel. The results of the verticality measurements can be displayed in a floor plan or in 3D view.
Documentation
Development of the Mixed-in-Place method has been continuous since the end of the 1980s, a fact reflected in more than ten current patents. In addition, the company
also holds a license from the “Institut für Bautechnik“ in Berlin. The term “MIP“ is protected as an EU Community trademark.
Dams and dikes
11Areas of application
Without a structural functionInner seals are introduced in order to reduce or prevent fl ow and thus increase the stability of the dikes. These walls are generally constructed starting from the crest along the dike axis. They are either embedded into layers
of low groundwater permeability or serve as an extension of the seepage path. The hardened cut-off wall materials must be able to withstand erosion and the dikes must be protected against burrowing animals.
With a structural functionIf inner seals are exposed to static load due to a dismantling of the slope shoulder on one side, the Mixed-in-Place cut-off wall is to be measured for this load case. Any absorption of a shearing force or moment load resulting from earth and water pressures will be protected against
by the installation of reinforcement cages or girders. The size and distance of the load-bearing elements as well as the compression strength required of the Mixed-in-Place materials are specifi ed in the static calculations.
Dams and dikes
Load case 1: water-side erosion Load case 2: air-side erosion
Inner seals prevent the complete through-flow of the dike
12 Areas of application
The dikes of the Großen Röder river and the Röderneugraben canal were severely damaged in the flood of September 2011 in the areas surrounding the Saxon town of Großenhain. Shortly afterwards, restoration or strengthening works began on the dikes. For this, a structurally effective Mixed-in-Place inner seal was introduced with adjusted supports. In order to complete the works on schedule, 24 hour operations were implemented even throughout the winter months.
Strengthening the dike at Großenhain
During the flood of June 2013, weak points became visi-ble to the south of the Chiemsee lake, at the dikes along the Tiroler Achen river. So far, a total of 25,000 m² Mixed-in-Place walls along three sections have been integrated for soil stabilization and sealing the dikes starting at the A8 and moving southward. At times, two Mixed-in-Place
drilling rigs were used at the right and left-hand sides of the river. Due to the limited space available for building site facilities, slurry had to be pumped in sections along a stretch of 1,300 m from the mixing equipment to the drilling rig. Coarse alluvial soils with high storage density required the use of special drilling tools.
Grassau flood protection
13Areas of application
After the 1999 Pentecost flood which caused immense damage along the Upper Iller, a master concept was developed for flood protection in this area. One of the key measures taken was the remediation of the dikes, which were provided with structurally effective cut-off walls. From 2001 to 2005, approximately 71,000 m² of (reinforced) cut-off walls using the patented Mixed-in-Place method were constructed in the sections between Kempten and Oberstdorf. During the flood of August 2005, the dikes faced a tough challenge sooner than expected, but the MIP wall held strong!
MIP wall secures the dams of the Upper Iller
Above the weir at Bad Abbach in Lower Bavaria, a canal branches off from the Danube to a large lock for com-mercial shipping. Seepage discharges were detected at the dam of the lock canal in the event of flooding.
Remediation of the dam was carried out with a Mixed-in-Place cut-off wall; jet grouting was used for realizing the connections to the existing pumping station.
Bad Abbach dam rehabilitation
14
For some time now, water flows have been detected at certain locations on the dams of the Grand Canal d’Al-sace. In order to prevent dam destabilization and the associated risk of material discharge, a total of 33,500 m² of Mixed-in-Place cut-off wall was built along the dam axis from July to December 2011. Using the virtually
vibration-free Mixed-in-Place method, wall depths of up to 18 m were realized in the abrasive, alluvial soils. Geo-thermal measurements taken before and after the wall construction confirmed the success of the measures taken. With a total surface area of over 70,000 m², this led to a successfully strengthening of the Rhein dams.
Dam remediation in France
The city of Regensburg is to see millions of euros in investment over the next several years toward the improvement of flood protection for the Danube River. In the second of a total of 18 sub-projects, dikes along the southern bank of the Danube, which at times merely consist of the banked side of a sewage collector, are being raised and provided with an inner seal. As an alternative to the sheet pile solution originally put forward in the tender, a cut-off wall in the Mixed- in-Place method was constructed. The low-vibration construction meant that less strain was placed on both the existing canal as well as on buildings located nearby such as St. Georg Church.
MIP wall for Regensburg Schwabelweis
Areas of application
15
About 100 km west of Vienna, the Danube flows through the Wachau valley, which remains undeveloped. The river regularly bursts its banks and floods into the adjacent localities, reaching up to the first floor of the buildings. After the devastating damage caused in Weißenkirchen in 2002, the decision was made to install a flood protec-tion wall. Bauer constructed the underground section, a Mixed-in-Place wall up to 10 m deep with adjusted supports. The anchor plates for the mobile protective barrier were integrated into the top bars, which are constructed as required by local authorities. During the June flood in 2013, the protection system put on an impressive display of its effectiveness.
Flood protection for the Wachau valley
In the tunnel under the Van Harinxma Canal at Leeuwar-den, the Netherlands, a total of 12,500 m² of Mixed-in-Place cut-off walls were constructed in the area around the tunnel ramps. The walls, which measured up to 18.50 m deep, were executed in predominantly cohesive soils, with low sand content. The depth of penetration in the impermeable clay layer amounted to approx. 2 m.
Considering the 100-year useful life of the cut-off wall, additional plastic sealing sheets were installed in each area. Sandy clay soil that is prone to settlement had collected in the drilling level area. Consequently, a work platform made of excavator mats was constructed, which securely held both of the devices weighing over 100 tons.
Tunneling of the Van Harinxma Canal
© www.wachaufoto.at
Areas of application
Der BAUER Anker16
17
Excavation pit enclosuresAn additional area of application for the MIP method is the encapsulation of excavation pits. The inherent system-related advantages of the method come into play, especially in urban spaces:
– Low-vibration construction using rotary drilling
– Limited drilling spoil by using the existing soil as an aggregate
– Lower impact on the surrounding areas due to reduced transport expenditures and shorter con-struction periods
MIP drilling rigs are equipped with a swing-type mast. These also allow for the construction of small-scale excavation pit enclosures within limited space conditions. The low height of the auger guide and the rotary drives allow work to be performed very close to existing buildings. As the drilling rigs, drilling tools and attachments are manufac-tured at Bauer, site-specific solu-tions are possible. To strengthen the walls for absorbing shearing forces or moments, steel girders or sometimes cages or piles are used as reinforcement elements and are incorporated into the soil/slurry mixture when it is still soft. A vault will form between these rein-forcement elements. The MIP retain-ing walls are integrated into the nat-ural impermeable layer or combined with the Bauer LWS sealing beds in order to create a sealed excavation trough.
Areas of application
18
Regarding the extensive wastewater network renova-tions in the city of Ansbach, the old, no longer viable sandstone vaults of the Dombach river were broken down and replaced by a reinforced concrete canal on Maximilianstraße. Mixed-in-Place retaining walls were applied for shoring works. The limited space available inside and outside the construction site as well as limited access opportunities posed special challenges. A splash guard was used in the directly adjacent area near the neighboring buildings. This guard was mounted to the triple auger and rolled and unrolled together with the movements of the leader rig. The installation of the reinforcing supports was carried out using a special excavator.
Shoring works in Ansbach
An office and residential buildings were created on the grounds of the former customs port in Mainz and adja-cent to the art gallery. The entire area was enclosed by a Mixed-in-Place retaining wall as the excavation base of the approx. 5,500 m² excavation pit lay below the Rhine‘s design water level. The wall formed a sealed trough together with the tertiary clays that are at a depth of 16 m. As the construction area was located directly on the Rhine, the Mixed-in-Place wall was used predom-inantly in the terrace deposits of the Rhine. This quater-nary, low gravel content sand, with its storage density that increases with depth, is the ideal Mixed-in-Place soil and allows for a very high drilling performance with low drilling spoil.
Dock 1 of customs port, Mainz
Areas of application
19
As part of the rerouting of the B 71 in the town of Salz- wedel, the Landesbetrieb Bau state office in Sachsen- Anhalt built a 180 m long trough construction under the Deutsche Bahn AG railway tracks and the newly created B 71. In total 5,000 m² of Mixed-in-Place retaining walls and sealant were produced. GEWI thread bars secured the 1 m thick underwater concrete slabs against uplift. The Mixed-in-Place wall was produced in sandy, silty soils but also in soft clay and peat layers. This heteroge-neous subsoil condition could be processed into a homogeneous soil-slurry mixture using vertical mixing with the triple auger.
B 71 trough construction, Salzwedel
Along the northern end of Leopoldstraße in Munich, a complex of apartments, offices, shops and a hotel was built. The plans are for up to 1,500 people to live and work on the grounds of the former metro market and of the legendary Schwabylon shopping center. The “Schwabinger Tor“ will become a center for innovation, housing multiple studios for creative projects. The site, at a size of 35,000 m², will be predominantly enclosed by Mixed-in-Place retaining walls. The Mixed-in-Place drilling rig here will also be equipped with a splash guard for each section. The device has a special con-struction which allows it to be fitted on all drilling rigs.
Schwabinger Tor, Munich
Areas of application
20
A housing development was built near Lake Lugano, on an surface area of 2,000 m². The tender originally envi-sioned an excavated diaphragm wall as the encapsulation for the 5.50 m deep excavation pit. The Mixed-in-Place wall with a maximum depth of 16.50 m was chosen as an alternative option. The excavation pit was stiffened using a strut set at the top.
A variety of very different soil formations have been encountered in the several applications of the Mixed-in-Place method in the city of Lugano. Both cohesive and coarse-grained soils could be reliably mixed with the Mixed-in-Place triple auger.
SAC Vismara, Lugano, Switzerland
A five-star hotel was built in keeping with the facades listed as protected historic monuments on Französische Straße. Due to the limited space available, the 80 t Mixed-in-Place drilling rig had to be placed and lifted with the help of a truck-mounted crane on the construction site. The 9 m deep excavation pit with 7 m difference in water levels was constructed using a stiffened or rather anchored Mixed-in-Place wall as well as a horizontal LWS cut-off. Work was carried out in sections for the existing buildings that are up to 30 m high and prone to settlement, the verticality of the wall was monitored online using inclination measurements in the triple auger.
Titanic Hotel, Berlin
Areas of application
21
After the demolition of a building from the postwar period, a new office building is being constructed on the Kurfürstendamm in Berlin-Charlottenburg. A sealed deep excavation wall is necessary for the two basement floors. These will be achieved using Mixed-in-Place retaining walls and a LWS sealing bed. The construction of the Mixed-in-Place wall was completed directly in front of the very high walls of the adjacent Gründerzeit houses. The up to 8.50 m deep excavation pit was tied back twice with anchors. The individual hard till layers that are embedded in the meltwater sands of Berlin‘s Urstromtal were easily drilled through. The compression strength of the hardened Mixed-in-Place mix was > 15 N/mm².
Kurfürstendamm, Berlin
The first sewage treatment plant in Munich, Gut Großlappen, was built in 1926 and operated as a two-stage biologi-cal plant with downstream filtration steps. During the renovations of the first biological stage, different settling pits, pumping and distribution buildings and installation ducts will be rebuilt. The excavation pits needed for this were up to 9 m deep and were enclosed with a total of 9,500 m² of Mixed-in-Place retaining walls. The walls, which measured up to 17 m deep, were executed in predominantly cohesive, tertiary soils, with only low gravel content. An RG 25 from the latest series was first used in January 2015. This device makes drilling depths of up to 21.50 m with the triple auger possible.
Großlappen sewage treatment plant, Munich
Areas of application
Der BAUER Anker22
23
For several years, the Mixed-in-Place method has been used for the production of foundation elements or for ground improvement. In addition to the triple auger, the so-called single augers are also often used for this. The Mixed-in-Place panels or piles can be arranged flexibly based on the structural requirements.
Depending on soil conditions, strengths between 1 MPa and more than 15 MPa can be achieved. Because the mixing effect of the single auger is less intensive than with the triple auger, a good knowledge of the in-situ subsurface conditions is necessary. In addition to the inherent system-related advantages of the Mixed-in-Place method, it is also important to point out the very high productivity.
Ground improvement
At the entrance to the UNESCO World Heritage Site, Bay of Kotor in Montenegro, a world-class resort with a five-star hotel from the group “One and Only“ and high quality villas, apartment buildings, clubs, cafes, restau-rants and shops was built. On a surface area of approxi-mately 26 ha and along a coastline of about 3.5 km, five building complexes were built with a constructed surface of approximately 35,000 m². Because the subsoil of
the project area consists primarily of loosely deposited fine-grained, non-cohesive soils and it was at a high risk for soil liquefaction during an earthquake, the decision was made to improve the subsoil below the objects. For this, approximately 240.000 m² Mixed-in-Place elements (individual elements as well as walls) were produced in the subsoil with up to 23 m depth and a wall strength of 550 mm.
Porto Novi Resort Village, Montenegro
Areas of application
BAUER Spezialtiefbau GmbHBAUER - Straße 186529 Schrobenhausen, GermanyTel.: + 49 8252 97- 0Fax: + 49 8252 [email protected]
905.
039.
2
04
/201
7
T
he s
pec
ifica
tio
ns a
nd t
echn
ical
dat
a ar
e p
rovi
ded
as
ind
icat
ive
info
rmat
ion
onl
y, w
ith
any
erro
rs a
nd m
isp
rint
s re
serv
ed.
