Ground Improvement Specialists

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2 is a design-build specialty geotechnical contractor offering expertise on ground improvement for sites with poor soil. We combine value engineering and innovative techniques to deliver practical, sustainable solutions that are a faster, more economical and less complicated alternative to piles and other deep foundations. Our versatile range of technologies includes: l Bi-Modulus Columns l Controlled Modulus Columns l Dynamic Compaction l Dynamic Replacement l Vacuum Consolidation l Rapid Impact Compaction l Vibrocompaction l Vibro Concrete Columns l Vibro Stone Columns/Vibro-Piers l Wick Drains Our broad range of technologies and design-build experience has been successfully used worldwide in the following applications: l Oil and Bulk Storage Tanks l Transportation l Industrial Warehouses l Commercial and Residential Buildings l Federal Buildings l Retail The Pittsburgh, PA headquarters of is the US branch of, an international specialty ground improvement contractor, and a member of the Soletanche Freyssinet Group, a world leader in specialized civil engineering and construction. The Soletanche Freyssinet Group includes ; Reinforced Earth; Soletanche Bachy, geotechnical and specialized civil engineering companies; Nicholson Construction Company, North American subsidiary of Soletanche Bachy; Freyssinet, specialists in prestressing, cable-stayed structures and structural repair; and Nuvia, a leader in the nuclear field. leverages its affiliations to provide clients with innovative, cost-effective solutions that extend our geotechnical resources and expertise.

3 Controlled Modulus Columns TM Controlled Modulus Columns (CMCs) are an environmentally sound and economical solution for strengthening soft ground when construction needs to begin within days instead of months. CMCs consist of grouted inclusions that work together with the surrounding soil to provide a stiff composite ground mass. CMCs are well adapted to high surface loading conditions and strict settlement requirements and are used to support slabs-on-grade, isolated footings, and embankments on compressible clays, fills and organic soils. Controlled Modulus Columns Applications Warehouses MSE Retaining Walls Industrial Facilities Bridge Abutments Storage Tanks Roadway Embankments Port Facilities Railway Embankments Controlled Modulus Columns uses a patented CMC technology that reinforces soil by drilling a hollow auger into the soft soil and installing a cement-based grout column using pressure through the hollow auger. The combined effect of densification and reinforcement improves characteristics of the soft ground resulting in a composite system. CMCs are installed using a specially designed auger that displaces the soil laterally, with virtually no vibration and no spoil, eliminating the need to dispose of contaminated soil. The auger is screwed into the soil to the required depth which increases the density of the surrounding soil and, as a result increases its load bearing capacity. During the auger extraction process, a column is developed by pressure-grouting to stiffen and treat the surrounding soil. The result is a composite ground improvement system where the column reinforcements and the surrounding soil share the loads. CRUST SOFT CMCs were developed by s French affiliate, Soltraitement, in 1994 and are patented in the US. The two companies have installed over 5 million feet of CMCs on hundreds of projects in North America and around the world. FIRM Controlled Modulus Columns (CMCs) are grouted columns formed using an auger that displaces soil laterally, producing very little spoil. As the auger is extracted, a column is formed using pressure grouting to achieve a predetermined stiffness ratio with the surrounding ground.

4 Bi-Modulus Columns Bi-Modulus Columns (BMC) are vertical ground improvement elements composed of a rigid inclusion topped with a compacted granular column. BMC combine the advantages of Stone Columns and Controlled Modulus Columns (CMC), so the upper soil is not over-stiffened and is more compliant in areas with high seismicity, the thickness of the Load Transfer Platform (LTP) required for rigid inclusions is reduced, and there is no risk of column buckling or bulging in deeper weak soils. The use of BMC creates a more robust system the upper granular part improving the load transfer mechanism and stress distribution from the structure or building to the rigid inclusion. This cost-effective technique optimizes the thickness of the LTP between the structure and inclusions. Bi-Modulus Applications Warehouses and Platforms Industrial and Commercial Buildings Residential Buildings Storage Tanks Road & Rail Embankments Retaining Walls Liquefaction Mitigation Bi-Modulus Columns BMC are installed in phases. The bottom part is installed in a process similar to a CMC, using a full displacement auger. At the design depth, the column is then grouted under moderate pressure to form the grouted inclusion. No extraction or soil mixing takes place during the grouting and no spoil is generated. The upper part is implemented by inserting a vibroflot into the grouted inclusion. Stone is then added and compacted by extraction and re-penetration until the interface and Stone Column are formed. Phase 1: CMC Phase 2: Stone Column This planned phasing ensures the effectiveness of the compaction of the granular tops as well as optimum mixing conditions between the ballast and the grout in the transition zone. The quality of the transition zone/stone column interface is a key component in the effective distribution and transfer of loads from the structure to the competent soil layers below. Bi-Modulus Columns (BMC) are an innovative combination of Controlled Modulus Columns and Stone Columns applied to create a transition layer and force distributon between the constructed structure and the subsoil reinforced with the columns.

5 Dynamic Compaction TM Dynamic Compaction is a cost-effective technique used for deep ground densification. High energy waves, created by the repeated impact of heavy weights, compact areas of loose granular soils, uncontrolled fills, or waste to increase density and collapse voids. Dynamic Compaction efficiently increases the bearing capacity of granular soils, reduces the volume of landfills and lowers post-construction settlements. Dynamic Compaction is commonly used to treat old uncontrolled fills, waste material and native granular soils to depths up to 50 feet. Dynamic Compaction Applications Airport Runways Landfills Buildings Treatment Plants Parking Lots Marine Terminals Roads and Roadway Storage Tanks Embankments Liquefaction Mitigation Dynamic Compaction Dynamic Compaction consists of repeatedly lifting and dropping heavy steel weights (pounders) weighing 15 to 40 tons from heights of 30 to 120 feet. The weights are dropped from a crane in virtual free fall. Results from a trial zone and the characteristics of the ground determine the location and grid spacing of impact points and other parameters such as energies, phasing and rest periods. Each point receives several blows per pass, and several passes may be required to achieve optimal results. When using Dynamic Compaction the removal and replacement of undesirable soil is not required. Dynamic Compaction applies energy at the ground surface and compacts relatively deep layers. The process is efficient, economical, and can be used to improve a wide range of soil types. The Dynamic Compaction technique was originally invented and developed by Mr. Louis and Soltraitement, s French affiliate. Dynamic Compaction was introduced in the US, by in 1978 and has been used successfully in numerous projects. Dynamic Compaction involves dropping heavy pounders (15 to 40 tons) on the ground from a significant height (30 to 120 feet) in accordance with a predetermined grid pattern. High-energy impacts create shock-waves that increase soil density at great depths.

6 Vacuum Consolidation Vacuum Consolidation is a proprietary system used for preloading and consolidating soft and very soft saturated fine-grain soils. Vacuum Consolidation is an efficient time-saving consolidation method; loading and construction can proceed as early as two weeks after the process has started. Vacuum Consolidation reduces settlement and increases bearing capacity. Vacuum Consolidation Applications Airport Platforms Marine Terminals and and Runways Port Platforms Roads and Roadway Treatment Plants Embankments Levees Bridge Abutments Storage Tanks MSE Retaining Walls Vacuum Consolidation Fill Atmospheric Pressure Draining Layer Impervious Membrane Vacuum Gas Phase Booster Vacuum Air Water Pump Vacuum Consolidation involves the installation of both vertical and horizontal vacuum transmission pipes and peripheral trenches. An airtight impervious membrane is then installed on the ground surface and sealed in the peripheral trenches. Vacuum Pumps are then connected to the system to remove the air below the membrane. This results in the creation of a vacuum under this membrane. The difference of pressure at the mem-brane interface creates a gradient resulting in the application of a pressure equivalent to the atmospheric pressure on the ground below the membrane. This loading process creates an isotropic state of stress in the soils under the membrane, accelerating the consolidation in the soil mass in a very short time, reducing the need for long term and potentially unstable surcharge loads. Air Flow Horizontal Drains Peripheral Drain Wall Vertical Vacuum Transmission Pipes The Vacuum Consolidation method saves time and significantly reduces the amount of surcharge material that is needed. The process almost instantaneously replicates the effect of a conventional 12 foot surcharge with Wick Drain system. The patented Vacuum Consolidation technique was developed in 1988 by s French affiliate, Soltraitement, and presents a method for rapid consolidation of clay soils that is unprecedented. Vacuum Consolidation consists of installing vacuum transmission pipes, peripheral trenches and an impervious membrane on the ground surface sealed in the trenches. Air is pumped from under the membrane and the resulting vacuum creates an isotropic stress in the ground equivalent to the atmospheric pressure or 12 feet of surcharge fill.

7 Dynamic Replacement Dynamic Replacement is an extremely economical method for improving the overall stiffness of clay, silt and organic soils. Dynamic Replacement uses granular backfill to form large diameter granular columns with high shear strength and great bearing ability through soft soils or waste fills. These columns remain stable under very low confining pressure. Dynamic Replacement Applications Airport Runways Treatment Plants Buildings Marine Terminals Parking Lots Storage Tanks Roads and Roadway Port and Airport Platforms Embankments Dynamic Replacement Dynamic Replacement is used to form granular columns with diameters of 6 to 8 feet to depths of up to 25 feet. A layer of coarse granular material is installed to provide a working platform and to confine soft surface soil. Dynamic Replacement columns are formed by driving the coarse material into the soil with 15 to 30 ton pounders, dropped from heights of 30 to 120 feet. The column is refilled with granular material, which is again compacted. The process repeats until the desired depth and column volume are achieved. These large diameter granular columns (also called inclusions) have a very high modulus of deformation therefore reducing post-construction settlements. They also help increase the factor of safety against global failure when used under embankments due to their very high shear strength and friction angle. Also acting as oversized vertical drains, Dynamic Replacement columns help reduce the consolidation time of compressible silts and clays. The Dynamic Replacement technique was developed in 1975 by Soltraitement, s French affiliate. Dynamic Replacement has been used successfully worldwide on a variety of projects. Dynamic Replacement columns are driven into the soil with a 15 to 30 ton pounder dropped from a height of 30 to 120 feet. The column is filled and compacted in alternating phases until it is completed.

8 Rapid Impact Compaction Rapid Impact Compaction is a ground improvement technique for shallow ground densification ranging from 15 to 20 feet. Energy is created using a hydraulic hammer to compact areas of loose granular soils, slabs or waste material. Rapid Impact Compaction is used to increase bearing capacity and reduce settlement. It is often used in low headroom sites or when the vibrations generated with traditional Dynamic Compaction equipment is challenging to near-by structures and/or excavation is cost prohibitive. Rapid Impact Compaction Applications Airport Runways Buildings Building Support in Seismic Areas Roads and Roadway Embankments Parking Lots Landfills Liquefaction Mitigation Rapid Impact Compaction uses a hydraulic hammer for shallow compaction of soft soils to increase density and reduce settlement. Rapid Impact Compaction Rapid Impact Compaction uses a hydraulic hammer, varying in weight from 7.7 to 9.9 tons, installed on a special mast on a large backhoe. Results from a trial zone and ground characteristics determine the location and grid spacing of the impact points. The impacts can be repeated at the rate of 40 or more blows per minute; applying a compactive energy of approximately 45,000 tonsfoot per hour, more or less equivalent to that applied with a conventional crawler crane and a 14 ton tamper. The limited height of drop, slightly less than 3 feet, and the weight of the available hammers limit the depth of improvement to about 15 to 20 feet.

9 Vibrocompaction Vibrocompaction is a ground improvement technique used in areas where weak and unconsolidated soils impose constraints on development. The main purpose of vibrocompaction is to densify in-situ soils by vibration. Vibrocompaction is commonly used to improve granular soils and bearing capacity prior to construction of foundations and slabs constructed for commercial, industrial and residential buildings; to reduce settlement in areas of landfills; and to reduce the potential of liquefaction. Vibrocompaction Applications Industrial Warehouses Commercial Buildings Residential Buildings Roadway Embankments Airport Runway Embankments Bridge Abutments MSE Retaining Walls Vibrocompaction vibrocompaction combines the action of the vibrating probe and saturation by water jetting to rearrange the soil particles in the borehole to a denser state. This action is repeated at predetermined intervals across the site. Sand backfill, from either on-site or off-site sources, is then typically placed and compacted with the vibroprobe at the compaction location in order to compensate for the reduction of volume resulting from the densification. Vibrocompaction is especially effective in areas of loose, clean sands and gravels. Vibrocompaction combines vibration and jetted water to create a localized liquefaction of the soil, allowing the grains to rearrange in a denser state. Typically the hole causes from extraction is backfilled by additional granular materials as the probe is removed.

10 Vibro Concrete Columns Vibro Concrete Columns are reinforced, compacted columns commonly used in areas that require higher loads and are installed through very soft soils (peat or other organic deposits) in order to transfer loads to more competent load-bearing strata. Vibro Concrete Columns are used in cases where the soils are so soft and unstable that installation of stone columns would be difficult, or where the stone columns would not have sufficient lateral confinement to adequately carry vertical loads. Vibro Concrete Columns Applications Industrial Warehouses Commercial Buildings Residential Buildings Roadway Embankments Airport Runway Embankments Bridge Abutments MSE Retaining Walls Vibro Concrete Columns Vibro technologies involve the use of a vibroflot, a vibrating probe suspended from a crawler crane. As the vibroflot is lowered, it penetrates weak soils until reaching the required depth. Depending on soil conditions and intended site use, a variety of techniques can be employed to create the compacted columns. Vibro Concrete Columns are accomplished by filling the borehole with concrete rather than stone. The vibroflot penetrates the soil until it reaches a suitable load-bearing stratum. Concrete is discharged at the bottom of the column to form an enlarged basal bulb, and then discharged continuously to form a column as the probe is withdrawn. Vibro Concrete Columns are installed by inserting the vibratory probe, injecting concrete through a side feeder tube to initially form a bottom bulb, and retracting the probe while continuing to inject concrete to form the remainder of the column.

11 Vibro Stone Columns Vibro Stone Columns are continuous vertical columns of dense interlocking aggregate that are formed by inserting a vibratory probe to incorporate granular material into the ground and create vertical inclusions with high stiffness, shear strength and draining characteristics. Vibro Stone Columns are a highly efficient and cost-effective solution for improving soil prior to construction of foundations and slabs for commercial, industrial and residential buildings; to reduce settlement in areas of landfills; and to reduce the risk of liquefaction under roadways, airport runways, embankments and bridges. Vibro Stone Columns Applications Industrial Warehouses Sewage Treatment Plants Commercial Buildings Railway and Roadway Embankments Residential Buildings Retaining Walls Container Terminals Liquefaction Mitigation and Building Support in Seismic Areas Vibro Stone Columns Under uniformly loaded structures such as embankments and slabs-on-grade, Vibro Stone Columns are installed on a regular grid spacing. In this case, a load transfer platform is designed and installed between the top of the columns and the structure. The Vibro Stone Columns installation results in a significant reduction of the total and differential settlements. Vibro Stone Columns can also be installed as a group to support isolated loads (shallow spread footings) or directly under linear loadings such as strip footing or retaining walls. In this case, Vibro Stone Columns increase the bearing capacity of the soil while reducing the magnitude of settlement. Vibro Stone Columns are formed by inserting a hydraulic or electric vibroflot equipped with a pressure chamber equipment (130 kw using air as a jetting fluid). This combination gives the best result for the incorporation of the granular backfill to the bottom of the system and warrants the continuity and optimum compaction of the columns.

12 Vertical Wick Drains Vertical Wick Drains are a cost-effective solution for accelerating the consolidation of fine-grained soils to expedite construction and limit longterm settlement. Used in combination with pre-loading, Vertical Wick Drains evacuate pore water from soft, compressible soils to induce consolidation and settlement. This allows construction to begin in one to three months instead of up to 12 months or longer. Using Wick Drains as a drainage path to reduce the water content also strengthens the underlying soil to accommodate superimposed loads and minimize future settlement. Vertical Wick Drain Applications Buildings MSE Retaining Walls Warehouses Airport Runways Storage Tanks Marine Terminals Bridge Abutments Dams Roadway Embankments Levees Roads Waste Sites Vertical Wick Drains uses state-of-the-art Vertical Wick Drains designed with high wat er flow capacity, high-resistance filtration properties and durable construction. The company has developed its own range of Vertical Wick Drain installation equipment to meet a wide variety of soil and site conditions. The company uses static and vibratory methods to install Vertical Wick Drains and has considerable experience in penetrating difficult surf ace layers including preaugering through stiff clays and special downhole drilling to penetrate rubble, concrete, slag and other types of fill. has angled Wick Drains up to 30 degrees and installed Wick Drains in low headroom areas. pioneered Vertical Wick Drains in the US and has successfully completed more than 800 Vertical Wick Drain projects worldwide, ranging from as small as 2,000 linear feet to well over 60 million feet. Vertical Wick Drains, also known as Prefabricated Vertical Drains or PV Drains, consist of a plastic core wrapped in geotextile fabric. Vertical Wick Drains greatly reduce the distance the water must move to reach a free drainage path; greatly decreasing time of settlement.

13 Corporate Headquarters Fax info@menardusa.com CLEVELAND OFFICE 9930 Johnnycake Ridge Road Suite 2H Mentor, OH Tel Fax GULF COAST OFFICE 3500 N. Causeway Blvd. Suite 160 Metairie, LA Tel Fax HOUSTON OFFICE Katy Freeway Suite 705 Houston, TX Tel PHILADELPHIA OFFICE 2424 E. York Street Unit #225 Philadelphia, PA Tel