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Tel:
(250) 756-0355

Fax:
(250) 756-3831

Email

Lewkowich Engineering Associates, Ltd.
Suite A-2569 Kenworth Road
Nanaimo, BC
V9R 3M4

Tel:
(250) 334-0384

Fax:
(250) 334-9601

Payment Forms Accepted:
Cheques, Purchase Orders, VISA, MasterCard

Business Hours:
8:30 am to 5:00pm
Mon - Fri

Services

Geotechnical soils investigation

LEA has the capabilities of conducting geotechnical evaluations for the following:

• Building foundations
• Roads and highways
• Subdivision soils assessments

Use of backhoe or excavator

This is our most preferred method of investigating subgrade soils. It offers the following advantages:

Advantages

• Relatively low cost
• Useful when accessing remote sites or sites with poor access characteristics
• Ability to closely assess near surface soil characteristics
• Availability of machines is quite high

Disadvantages

• Useful only with upper 5 to 6m
• Incapable of performing soil characteristics testing such as Standard Penetration Testing, Shelby Tube extraction or shear vane testing.
• Generally used for small-scale investigations or preliminary assessments.

Auger drilling rig

Useful in deeper soils investigations in soils above glacial till or bedrock, particularly normal consolidated clays or silts.

Advantages

• Capable of performing various field tests such as Standard Penetration Testing, Shelby Tube extraction or shear vane testing.
• Causes less disruption to the ground surface
• Ability to assess sub-surface soil characteristics qualitatively
• Used for installation of piezometers, slope indicators and other monitoring devices

Disadvantages

• Useful only within upper 15m
• Relatively high cost
• Availability of machines is quite low
• Not useful in harder materials such as glacial till or rock
   

Air track drilling rig

Advantages

• In combination with piezocone can provide very accurate assessments of soft clay deposits
• Rigs can be utilized for rock-coring

Disadvantages

• Availability of rigs can be a problem
• More time-consuming and potentially expensive

Becker Hammer Rig

Advantages

• Can penetrate very dense soils for very deep investigations
• Useful for larger scale projects such as dams, industrial installations and deep foundations.
• Rig is useful to assess piling characteristics

Disadvantages

• High mobilization and operating costs
  Soils are highly disturbed during penetration

Sonic Drilling

Uses high frequency vibration and rotation

Advantages

• Can provide a continuous "core" of soil from surface to significant depths
• Useful in penetrating very dense till and bedrock deposits

Disadvantages

• High mobilization and operating costs
• Soils are highly disturbed during penetration
   

Mud Rotary

Uses tri-cone and mud to maintain test hole sidewalls.

Advantages

• Useful in soft or sloughing deposits
• Can be used to effectively drill through very dense deposits
• Rigs can be utilized for rock-coring

Disadvantages

• Site investigations can be messy
• High mobilization costs

Foundation inspection and remediation

Upon completion of our geotechnical investigation and when construction commences, it is generally deemed necessary to inspect soils for conformance to our soils report

As can often occur, soils found in drill-holes or test pits may differ from those found during subsequent investigations. LEA should assess sub grade soil conditions during construction to ensure that recommendations provided in the report reflect the actual site conditions. Generally LGE should assess soil characteristics when foundations are being prepared. In the case of strip or pad footings, this should be conducted prior to pouring of footings. In the case of deep foundations, LEA should be on-site during pile installation.
 

Foundation design

Shallow foundation design.

Includes soil-bearing capacity for strip or pad footings.

If grade changes are necessary, LEA can call upon their extensive site experience to determine the most cost effective method of raising site grades, whether by placement of structural fill, raised foundations or piles.

Deep foundation design

LEA has extensive experience in deep pile foundation design. These include timber pile, pre-stressed concrete, steel pipe, driving shoe, H-pile.

Groundwater/site drainage assessment and remediation

LEA can provide recommendations and monitor short-term or long-term site drainage considerations. Vancouver Island has unique wet weather patterns that result in the need for specific and innovative site drainage considerations.

Capabilities include:

• Footing drainage
• Sub-slab drainage
• Slope drainage
• French drain design and installation
• Temporary construction drainage
• Deep wick-drain installation and monitoring

Setback determinations

• LEA can provide recommendations for setbacks for government Legislation requirements
  
• LEA can provide recommendations for determination of "natural grade"
  

Geotechnical hazard assessments

• LEA can provide recommendations for slope failure remediation and shoring
  
• LEA can assess foundation failures and structure failures. These include failures as the result of poor construction, soil bearing failures and settlement.
  
• LEA can provide recommendations for earthquake preparedness and foundation upgrading.

Slope stability analysis

• LEA utilizes various methods for assessing the stability of slopes. These include site survey, field evaluation, air-photo interpretation, topographical studies and weather studies.
• LEA can assess rock, soil or retained earth slopes.

Retaining wall design - providing proven and cost-effective designs

• LEA has extensive experience in the design and construction monitoring of reinforced, modular block structures, which enables us to provide substantial cost savings in building retaining walls. Our awareness of construction efficiencies and materials selection has often resulted in cost savings to the contractor of more than twice the engineering costs.

Soil classification, grain size analysis, moisture density (proctor) and other engineering properties testing

• LEA can conduct various geotechnical laboratory testing including (but not limited to) Atterberg limit testing, gradation testing (mechanical and hydrometer) soil permeability testing.
  
• In addition, through various partnering agreements with other larger geotechnical engineering firms, we can also provide dynamic shear analysis testing, consolidation testing, triaxial testing and other specialized testing.

Concrete testing

• CSA Certified Concrete Testing

• Field and laboratory concrete testing capabilities.

• Certified to Category 0 with the Canadian Standards Association

• Capabilities to conduct mix designs, aggregates analysis, specialized concrete mixes and admixtures

• Concrete mix design reviews and consulting

• Concrete coring for compressive strength, voids analysis and corrosion detection

• Reinforcing steel inspection and anchor bolt testing

Soil compaction testing

• Nuclear densometer compaction testing capabilities
• Sand Cone and balloon testing
• Large volumetrics such as sand and water replacement testing

• Routine metric and standard sieve series
• Field gradation crusher monitoring and testing to MOTH Standards

Asphalt concrete testing

• Full asphalt Marshall testing using either burn off oven, centrifuge or reflux extraction methods
• Asphalt plant calibration capabilities
• Asphalt coring for thickness and density determinations
• Asphalt mix design
• Recycled asphalt mix assessment and monitoring
• Pavement management systems setup and maintenance

Benkelman beam testing

• Two Benkelman beams for roadway or road structure deflection testing.

Certified with the BC On-Site Sewage Association (BCOSSA) for on-site sewage disposal system design.

Class 2 Engineered

With new pending Legislation slated to take effect in April of 2005, LEA is fully prepared to assume the requirements of the BC Ministry of Health in the design of on-site sewage disposal systems with flows up to 5000 Igal per day. (Subject to final certification)

Class 3 Tertiary

This would include non-engineered Class 1 systems to engineered Class 3 Tertiary systems.

Subdivision assessments and approvals

LEA is fully familiar with the Vancouver Island Subdivision Assessment Standards of the Ministry of Health. LEA has extensive experience in the determination of suitable septic covenant sizes and locations. LGE has an excellent working relationship with the various regulatory authorities such as Ministry of Transportation (MoT), Regional Districts and municipalities.

Site feasibility

In addition, LEA has experience in determining the drainage characteristics of a site using septic field evaluation techniques.