GEOTECHNICAL ENGINEERING SERVICES
Geotechnical Investigation
The foundation for any construction project starts with the ground upon which it’s built. As one of the providers of geotechnical services, it is our responsibility to explore below the ground surface. Most fundamental elements of the construction project is to identify a site's subsurface characteristics and composition of the site's soil and rock. Geotechnical investigation and assessments are used to collect and analyze data to better understand subsurface conditions. .
Purpose of geotechnical investigation
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Steps involved in geotechnical Investigation
Utility clearance for subsurface Investigation
- We will position investigation locations based on the mapping provided by the client.
- We assume testing locations will be accessible concurrently hat the truck and trailer parking access will be available on-site for our equipment.
- The confirmation of testing locations are cleared of utilities prior to mobilization. Therefore, before beginning of soil borings, we will clear utilities as required by law. If authorized by the client, we will retain a third party private utility locator to locate utilities and clear boring and testing locations for an additional cost.
Mobilization of drilling equipment and drilling and field
- We will mobilize a track mounted drill rig, drilling crew, and field representative. The field representative will observe drilling activities and classify soil samples in conformance with the approved standard procedure.
- The subsurface investigation will consist of drilling and collection of soil samples to the depth specified by the client.
- Standard penetration tests will be conducted to provide information on the properties of soil, while also collecting a disturbed soil sample for grain-size analysis and soil classification.
- Topsoil testing will include in-place depth measurement and laboratory testing for pH, organics, and nutrient analysis.
Subsurface Investigation Procedure
- Soil boring and infiltration testing locations will be backfilled with auger cuttings. If insufficient material is available to backfill the borehole, sand will be added. Asphalt will be capped with cold patch. Turf will be replaced in lawn areas
- Findings will be presented in a geotechnical report. The report will provide the information requested in the RFP including boring logs, laboratory testing results, and an analysis of the subsurface conditions encountered. The report will be provided in PDF format and include the recommendations requested in the RFP
Insite Tests
- A dynamic cone penetration tests is in situ test in which a weight is manually lifted and dropped on a cone which penetrates the ground. the number of mm per hit are recorded and this is used to estimate certain soil properties. This is a simple test method and usually needs backing up with lab data to get a good correlation.
- A cone penetration test (CPT) is performed using an instrumented probe with a conical tip, pushed into the soil hydraulically at a constant rate. A basic CPT instrument reports tip resistance and shear resistance along the cylindrical barrel. CPT data has been correlated to soil properties.
Insite Tests
- Standard penetration test is an in-situ dynamic penetration test designed to provide information on the properties of soil, while also collecting a disturbed soil sample for grain-size analysis and soil classification.
- A dynamic cone penetrometer test is an in situ test in which a weight is manually lifted and dropped on a cone which penetrates the ground. the number of mm per hit are recorded and this is used to estimate certain soil properties. This is a simple test method and usually needs backing up with lab data to get a good correlation.
Insite Tests
- A cone penetration test (CPT) is performed using an instrumented probe with a conical tip, pushed into the soil hydraulically at a constant rate. A basic CPT instrument reports tip resistance and shear resistance along the cylindrical barrel. CPT data has been correlated to soil properties.
Insite Tests
- Soil boring and infiltration testing locations will be backfilled with auger cuttings. If insufficient material is available to backfill the borehole, sand will be added. Asphalt will be capped with cold patch. Turf will be replaced in lawn areas
- Findings will be presented in a geotechnical report. The report will provide the information requested in the RFP including boring logs, laboratory testing results, and an analysis of the subsurface conditions encountered. The report will be provided in PDF format and include the recommendations requested in the RFP
Laboratory testing
A wide variety of laboratory tests performed on soils to measure a wide variety of soil properties.
Water content test: This test provides the water content of the soil, normally expressed as a percentage of the weight of water to the dry weight of the soil.
Atterberg limits: The Atterberg limits define the boundaries of several states of consistency for plastic soils. The boundaries are defined by the amount of water a soil needs to be at one of those boundaries. The boundaries are called the plastic limit and the liquid limit, and the difference between them is called the plasticity index. The shrinkage limit is also a part of the Atterberg limits. The results of this test can be used to help predict other engineering properties.
Particle-size analysis: This is done to determine the soil gradation. Coarser particles are separated in the sieve analysis, and the finer particles are analyzed with a hydrometer. The sieve analysis shakes the sample through progressively smaller meshes to determine its gradation. The hydrometer analysis uses the rate of sedimentation to determine particle gradation.
Soil compaction tests: Standard Proctor tests are used to determine the maximum unit weight and optimal water content a soil can achieve for a given compaction effort.
Geotechnical engineering services include:
- Subsurface Investigations, Sampling & Testing
- Slope Stability Analyses
- Retaining Structure Design
- Landslide Assessment/Remediation
- Pavement Evaluation, Rehabilitation & Design
- Mine Subsidence Investigations, Risk Assessments & Stabilization
- Geo-Hazard Assessments
- Building Foundation Design Recommendations
- Grouting and Ground Improvement Design
- Geotechnical Forensic Engineering
- Infiltration Testing
FOUNDATION DESIGN
Definition of Foundation
Foundations are structural systems on the ground to support various forces resulted by resulted structures like buildings, bridges, pavements etc. Foundation design is the creation of a construction plan for a building foundation. It is a highly specialized function and usually performed by a structural engineer. The foundation is the structural base that stands on the ground and supports the rest of the building. Therefore, foundation design must involve extensive study of the ground below the foundation as well as the design and materials used on the foundation itself. The foundations are shallow and deep. e.
Types of Foundations
In general, foundations are divided into two categories, shallow and deep foundations. The terms Shallow and Deep Foundation refer to the depth of the soil at which it is placed. Generally, if the width of the foundation is greater than the depth, it is labeled as the “Shallow Foundation” and if the width is smaller than the depth of the foundation, it is called a “Deep Foundation.
Shallow Foundation
Several types of shallow foundations are discussed below.
Foundation systems are divided into shallow and deep foundations. Shallow foundations almost always cast a grade on earth. The site is excavated to relatively shallow depths underneath the existing ground surface. Shallow foundations are used when the load is transferred into a bearing soil located at a about 3 feet deep. Shallow foundations are more popular because they are easier to construct and economical.
Shallow Foundation
Several types of shallow foundations are discussed below.
Foundation systems are divided into shallow and deep foundations. Shallow foundations almost always cast a grade on earth. The site is excavated to relatively shallow depths underneath the existing ground surface. Shallow foundations are used when the load is transferred into a bearing soil located at a about 3 feet deep. Shallow foundations are more popular because they are easier to construct and economical.
Deep Foundation
Deep foundations are used when the load is transferred into deep strata ranging from 60-200 feet. Dee foundations are more commonly found on sites where the soil conditions are poor. The process of constructing a deep foundation is more complex and costly and it requires heavier equipment and skilled labor. Deep foundations can be driven into the ground or cast against the earth, soil is much harder to excavate, and soil pressure increases as it goes deeper. A deep foundation provides lateral support, resists uplift, and supports larger loads and it relies on both end bearing and skin friction.