東京ソイルリサーチ List of Products and Services

As a good partner from the ground to the building, we contribute to the development of society with specialized skills and personnel to support people's safety and peace of mind, and to coexist with nature. Since our establishment, Tokyo Soil Research has upheld the corporate philosophy of "providing accurate and high-quality ground information" and has established a system to offer consistent technology from ground to foundation to building. Additionally, with a broad perspective on the future of society, we are committed to the refinement and development of technology, the sustainable provision of high-quality information, and the training of engineers to support these efforts, thereby contributing to the reduction of our customers' risks and the enhancement of their outcomes. 【Business Activities】 ■ Ground Investigation ■ Disaster Prevention ■ Structural Investigation and Design ■ Tsukuba Comprehensive Testing Laboratory ■ Environmental Conservation ▽ Please visit the Tokyo Soil Research website from the "Related Links."

• Geological Survey Company

At the Tsukuba Comprehensive Testing Center, we conduct field measurement operations that differ from typical ground investigations, including experimental work commissioned by various research institutions, various static and dynamic testing operations, as well as pile integrity tests and rapid load tests on piles. ■ Field Measurement Operations - Pile Integrity Tests (IT Tests) - Rapid Load Tests - Borehole Camera ■ Indoor Dynamic Testing Operations - Repeated Simple Shear Tests - Hollow Cylinder Shear Tests - Repeated Large-Scale Triaxial Tests - Small-Scale Triaxial Tests - Measurement of Soil Shear Wave Velocity using the Bender Element Method ■ Consulting In experimental work and various indoor static and dynamic testing operations, as well as field measurement operations such as pile integrity tests and rapid load tests, we collaborate with internal departments and partner companies, leveraging our long-cultivated technical expertise to comprehensively address our customers' challenges. ■ Experimental Work We receive numerous experimental commissions from various research institutions. Using the laboratory's experimental equipment, we conduct centrifugal loading experiments and shaking table tests, which involve the creation of model ground and model structures, as well as experimental measurements and data analysis. The structures we focus on include bridge abutments, embankments, reinforced earth walls, buried pipes, dams, and more. For these achievements, we have received excellence awards and engineer awards from the Public Works Research Institute.

• Geological Survey Company

"Original Position Freezing Sampling" is a technique for collecting undisturbed samples from sandy and gravelly soil layers. Sampling is conducted in a frozen state through core drilling from the frozen ground. Furthermore, by handling the samples in a frozen state from the time of sampling until just before the soil tests, we can provide high-quality samples with minimal disturbance effects. This technique is applicable to non-cohesive soils such as sandy soils, gravelly soils, and rock materials. [Ground Conditions and Sampling Conditions] ■ Ground with high saturation necessary for freezing ■ Ground with low fine particle content ■ Ground that can achieve moderate confining pressure ■ Freezing occurs in a state where pore water can escape outward from the freezing pipe ■ Sampling is conducted from areas away from the freezing pipe *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

We conduct "investigations and tests for structural surveys." In "concrete core sampling," we use a concrete boring machine. It is used to examine various concrete properties such as compressive strength, static elastic modulus measurement, carbonation testing, mix estimation, and chloride analysis. Additionally, we also handle "concrete compressive strength tests," "concrete carbonation tests," "rebar investigations," "building differential settlement, tilt, and floor slab deflection investigations," and "steel frame investigations." 【Investigation/Test Items】 ■ Concrete core sampling ■ Concrete compressive strength test ■ Concrete carbonation test ■ Rebar investigation ■ Building differential settlement, tilt, and floor slab deflection investigation ■ Steel frame investigation *For more details, please refer to the PDF document or feel free to contact us.

• Structural Survey
• Non-destructive testing

In our country, disasters such as landslides, slope failures, debris flows, and falling rocks are occurring in various regions. To prevent such disasters, our company assesses the level of danger through geological surveys and demonstrates comprehensive capabilities from observation and inspection to analysis, proposal of countermeasures, and design, contributing to various disaster prevention projects. In recent years, we have also been engaged in safety evaluations of slopes during construction and land development planning in accordance with the enforcement of the Sediment Disaster Prevention Act, as well as disaster prevention design. [Content (partial)] ■ Inspections, etc. - Stability and shape surveys of floating and rolling stones to understand the risk of falling rocks and the energy of falling rocks. ■ Geological Surveys - Horizontal boring to investigate the range of looseness along slopes. - Vertical boring to investigate the thickness of collapsed soil. *For more details, please refer to the PDF document or feel free to contact us.

• Civil Engineering Design Office
• Geological Survey
• Architectural design office

To create design input seismic motions that take into account the characteristics of "long-period pulses" and "long-period, long-duration seismic motions," it is very important to evaluate the source, propagation path, and ground amplification characteristics. By applying new seismic motion predictions, our company, which specializes in ground surveys, will conduct ground modeling and response analysis to provide appropriate design input seismic motions based on the site conditions of the planned building. Please feel free to contact us when needed. 【Main Content】 ■ Boring surveys, PS logging, continuous microtremor analysis, etc. ■ Evaluation of seismic motions based on past damaging earthquakes and simplified methods, etc. ■ Semi-empirical methods, theoretical methods, hybrid methods, etc. ■ Equivalent linear analysis, sequential nonlinear analysis, etc. *For more details, please refer to the PDF materials or feel free to contact us.

• Structural Survey

In the 1995 Hyogo Prefecture Southern Earthquake, significant damage was observed in buildings constructed under the old standards prior to the seismic design code established in 1981. To understand the seismic performance of these buildings and ensure seismic safety, it is necessary to conduct a "seismic diagnosis." In this diagnosis, the seismic performance of the building is evaluated by comparing the structural seismic index (Is) calculated for the building with the structural seismic judgment index (Iso) required for that building. 【Structural Seismic Index (Is)】 ■ The Is value is calculated for each floor and direction of the building. ■ Is = Eo × SD × T - Eo: Basic performance index derived from strength and ductility - SD: Shape index, a correction factor based on shape and weight balance - T: Age index, a correction factor for aging deterioration such as cracks, deformation, and aging *For more details, please refer to the PDF materials or feel free to contact us.

• Structural Survey

At Tokyo Soil Research, we offer "Reinforcement and Renovation Design" services. Buildings that require seismic retrofitting need to have a set renovation target level, which is generally based on an Is value of approximately 0.6 and a CTUSD of approximately 0.3 as a principle. However, considering the construction precision and difficulty of seismic retrofitting work, the accuracy of seismic diagnosis methods, and the uncertainty of seismic motion levels, we ensure a comfortable level of seismic performance. 【Reinforcement Methods (Partial)】 ■ Addition of seismic walls ■ Addition of braces ■ Addition of wing walls ■ Reinforcement of buttresses and frameworks ■ Reinforcement of columns (steel plate wrapping, carbon fiber wrapping) ■ Reinforcement of beams *For more details, please refer to the PDF materials or feel free to contact us.

• Renovation and repair methods
• Structural Design Office
• Structural Survey

During earthquakes caused by active faults occurring directly beneath urban areas or by massive earthquakes at plate boundaries, one of the causes of significant damage to buildings is considered to be the "resonance phenomenon between buildings and the ground." By installing microtremor measurement devices on both buildings and the ground and conducting simultaneous measurements, it is possible to confirm vibration characteristics such as "natural period," "vibration mode," "twisting period," "damping constant," and "relationship with the predominant period of the ground." "Microtremor measurement" involves measuring very small vibrations in a natural state. As a non-destructive testing method, it does not damage the building, and if conducted before and after seismic retrofitting of the building, it is also possible to confirm changes in rigidity through periodic changes. 【Items that can be confirmed】 ■ Natural period of the building and ground ■ Vibration mode of the building ■ Twisting period of the building ■ Damping constant of the building *For more details, please refer to the PDF document or feel free to contact us.

• Structural Survey
• Non-destructive testing

At Tokyo Soil Research, we conduct "investigations of retaining walls and slopes." A retaining wall is a structural element that supports the sides of cuts and fills to prevent landslides in areas that cannot maintain stability in their natural state. When there are retaining walls or slopes on the property, when conducting development activities, or when there are concerns about the safety of existing retaining walls or slopes, an investigation and assessment of their safety is necessary. Please feel free to contact us when you need our services. 【Investigation Items (Partial)】 ■ Shape Investigation ■ Deformation Investigation ■ Durability Investigation ■ Stability Investigation (investigation of the back and supporting ground) ■ Concrete Testing *For more details, please refer to the PDF document or feel free to contact us.

• Structural Survey

"Elastic wave exploration (refraction method)" is a method that observes the propagation of elastic waves, artificially generated by explosions on the surface or underground, as they travel through geological layers, either directly or refracted, using measurement devices installed on the surface. The results are then analyzed to elucidate the underground structure. In Japan, a survey regarding the thickness of riverbed gravel layers for dam construction was conducted in Yamagata Prefecture in 1931, marking the first implementation of refraction seismic exploration in the domestic civil engineering field. This method is almost invariably conducted in geological surveys for civil engineering structures such as tunnels, dams, railways, roads, and land development. 【Implementation Procedure】 ■ Formulation of the survey plan ■ Approval from the client, application for explosives transfer and consumption permit, local negotiations, etc. ■ Surveying and setting measurement lines ■ On-site measurement work *For more details, please refer to the PDF materials or feel free to contact us.

• Site and ground investigation
• Geological Survey

"Elastic Wave Velocity Logging (PS Logging)" measures the depth-wise velocity distribution of elastic waves (P-waves and S-waves) propagating within the ground using boreholes. There are two types of elastic waves propagating through the ground: P-waves (longitudinal waves), where the direction of vibration aligns with the direction of propagation, and S-waves (transverse waves), where the direction of vibration is perpendicular to the direction of propagation. This test can be conducted on all types of ground, from soft soil to bedrock. [Information Obtained] ■ Elastic Wave Velocity: P-wave Velocity (Vp) and S-wave Velocity (Vs) ■ Moist Density: Density Logging, Soil Testing, and Others (Estimation) ■ Dynamic Elastic Coefficients: Poisson's Ratio (νd), Young's Modulus (Ed), and Shear Modulus (Gd) ⇒ Use of Results: Modeling of ground for seismic design and earthquake response analysis *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

To conduct seismic design of structures rationally, it is necessary to accurately understand the properties of the ground directly beneath the foundation and the surrounding soil. In the "Repeated Triaxial Test," tests are conducted to obtain the constants necessary for determining soil liquefaction and to assess the repeated deformation characteristics of the ground required for seismic response analysis. Additionally, high-precision measurements of displacement using unsaturated liquefaction tests and LDT (local displacement transducer), as well as P-wave and S-wave velocity measurements using bender elements, are also possible. 【Obtained Constants (Partial)】 ■ Repeated Triaxial Test (Liquefaction Characteristics): R ■ Repeated Triaxial Test for Deformation Characteristics: G, H, γ ■ Static Triaxial Test: C, φ ■ Unsaturated Liquefaction Test: R ■ Axial Strain Measurement using LDT: E, ε1 *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

To accurately grasp the strength and deformation characteristics of ground composed of coarse-grained materials such as gravel, it is necessary to conduct tests using specimens of dimensions corresponding to the gravel diameter. The "Repeated Large Triaxial Testing Machine" has been developed to accommodate specimens up to 300mm in diameter. It also has the loading capacity to handle high-strength materials such as soft rocks. In this test, static strength and liquefaction strength, as well as repeated deformation characteristics, permeability coefficient, shear wave velocity, axial strain measurement using LDT, and Poisson's ratio constants can be obtained. 【Obtained Constants】 ■ Static Strength: C, φ ■ Liquefaction Strength: Rl ■ Repeated Deformation Characteristics: G～γ, h～γ ■ Permeability Coefficient: k15 ■ Shear Wave Velocity: Vs ■ Axial Strain Measurement using LDT: E, ε1 ■ Poisson's Ratio: ν *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

To conduct seismic design of structures rationally, it is necessary to accurately understand the properties of the ground directly beneath the foundation and the surrounding soil. The ground failure phenomena that often occur during major earthquakes are significant factors that greatly affect the seismic resistance of the superstructure. The "hollow torsional shear test" applies torque to the upper end of a hollow cylindrical specimen, twisting it in the circumferential direction to induce shear deformation throughout the specimen. Compared to indirect shear tests, it has the advantage of being able to relatively faithfully reproduce the stress and deformation conditions of the original ground. 【Types of tests that can be conducted】 ■ Torsional shear test ■ Repeated torsional shear strength test (liquefaction characteristics) ■ Repeated tests to determine deformation characteristics *For more details, please refer to the PDF materials or feel free to contact us.

• Site and ground investigation
• Geological Survey

To accurately grasp the deformation characteristics of ground materials, triaxial compression tests using LDT are effective. LDT (Local Displacement Transducer) is an axial strain measurement device attached to the side of the specimen, capable of measuring small strains accurately with minimal influence from bedding errors. Bedding error refers to measurement errors caused by deformations due to looseness at the upper and lower end faces of the specimen, incomplete contact between the specimen and the cap/pedestal, and elastic deformations of the cap/loading piston. 【Application Range】 ■ Applicable Soil Types - Hard ground materials (hard clay, soft rock, cement-treated soil, gravel) ■ Test Dimensions - φ50, H100 to φ300, H600 mm *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

The "Automatic Ram Sounding Test" automatically drops a hammer weighing 63.5 kg from a height of 500 mm, recording the number of blows (Nd) required for the tip cone to penetrate 200 mm. The Nd value obtained from this test is considered to be approximately equal to the N value from the standard penetration test. Note that sample collection, as done in the standard penetration test, is not possible. Additionally, it can measure sandy soils with an N value of around 30 to 50, and cohesive soils with an N value of about 20. 【Test Machine Features】 ■ Dynamic cone penetration testing machine developed by Borro in Sweden ■ Dimensions: Height 2.8m × Width 0.8m × Depth 0.9m ■ Total machine weight: 215 kg ■ Hammer weight: 63.5 kg ■ Hammer drop height: 500 mm ■ Hammer drop frequency: 24 times/minute *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

When designing structures and predicting ground deformation, it is necessary to confirm the strength characteristics, deformation characteristics, and consolidation characteristics of the ground. To verify these, there are methods to conduct investigations in situ, but it is common practice to collect undisturbed samples from the ground under consideration and perform appropriate laboratory soil tests. "Tube sampling" is one method of collecting undisturbed samples by lowering a sampler to the bottom of a borehole and either pressing it in or rotating it to obtain the sample. [Types of Samplers (Partial)] ■ Fixed piston type thin-wall sampler ・Hydraulic type / Extension rod type ■ Rotary double-tube sampler ■ Rotary triple-tube sampler ■ Rotary sleeve-integrated double-tube sampler *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

"Indoor soil quality testing" is conducted to quantitatively and scientifically assess the properties of the collected soil. There are various types, including sieve analysis, permeability tests, CBR tests, and liquid and plastic limit tests, which are mainly standardized by Japanese Industrial Standards (JIS) and the Japan Geotechnical Society (JGS). Please feel free to contact us when you need our services. [Main types of soil quality tests (partial)] <Classification: Physical tests> ■ Soil particle density test ■ Water content test ■ Grain size test ■ Liquid limit and plastic limit ■ Shrinkage constant test, etc. *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

The "In-hole Load Test" involves pressurizing the borehole walls using gas pressure or hydraulic pressure, and from the relationship between the pressure at that time and the displacement of the borehole walls, it determines the mechanical properties of the ground such as the deformation coefficient, ground reaction coefficient, yield pressure, ultimate pressure, and at-rest earth pressure. This method can be applied to all soil types and rock formations at any depth, as long as the borehole walls do not collapse. Since the measurement results can be affected by the finish of the borehole walls, testing devices such as trimmer methods and self-boring types have been developed to minimize disturbances to the borehole walls. [Types of Testing Equipment] ■ Single Chamber Type: Uniform Load Method - The measuring tube consists of a rubber tube measuring cell with one chamber. ■ Three Chamber Type: Uniform Load Method - The measuring tube consists of a main measuring cell made of rubber tube and upper and lower guard cells. ■ Borehole Jack: Uniform Displacement Method - Part of the cylindrical borehole jack consists of a metal loading plate. *For more details, please refer to the PDF document or feel free to contact us.

• Site and ground investigation
• Geological Survey

We provide a one-stop service from the planning and implementation of survey projects to the preparation and submission of reports, in collaboration with various departments within our company and partner companies. Additionally, we offer a range of services beyond just boring surveys, allowing us to provide complex proposals tailored to our customers' needs. 【Survey and Testing Contents】 ■ Boring Surveys ■ Sounding ■ Sampling ■ Freezing Sampling (please refer to detailed information) ■ Indoor Soil Testing ■ In-situ Testing ■ Creation of Input Seismic Motion for Design (please refer to detailed information) We conduct surveys for high-rise buildings, leisure facilities, buried cultural properties, and energy-related facilities such as power and oil, with over 2,000 survey achievements annually. We have our own testing laboratories in Kanagawa Prefecture, Ibaraki Prefecture, and Osaka Prefecture, where we conduct soil tests on physical properties, strength, and deformation characteristics of soil samples collected from boring surveys. Please feel free to contact us if you have any requests. *For more details, please download the PDF or contact us.

• Geological Survey Company

The Structural Investigation and Design Division started in 1976 with the investigation, diagnosis, and reinforcement design of old earthquake-resistant buildings. In response to customer requests, it has expanded its scope of work to include various structural investigations, diagnoses, and new structural designs. We conduct over 200 diagnoses and reinforcement designs annually, including deterioration investigations of existing buildings, deterioration diagnoses, evaluations of seismic safety through seismic diagnoses, and reinforcement and renovation designs to improve seismic performance. ■ Various on-site investigations and tests ■ Seismic diagnosis of buildings, seismic reinforcement design, obtaining evaluations, deterioration investigations, diagnoses, and fire damage investigations ■ Investigation and diagnosis of building ceilings ■ Measurement of the strength of school buildings ■ Current condition investigation of existing buildings without inspection certificates ■ Investigation, diagnosis, and reinforcement of historical buildings ■ Investigations for the reuse of existing buildings ■ Damage classification judgment and recovery design for earthquake-damaged buildings ■ Investigation and diagnosis of non-structural components ■ Investigation and diagnosis of existing block walls, etc. ■ Structural design of new buildings ■ Consulting services related to architecture overseas 【Investigations and Tests】 ■ Compressive strength tests of concrete and carbonation tests ■ Differential settlement investigations ■ Rebar investigations ■ Dimensional measurement investigations ■ Steel frame investigations ■ Deterioration condition investigations ■ Ceiling investigations

• Geological Survey Company

Our country has a complex topography and geology, and due to the weak ground, ground disasters occur frequently. We will contribute to regional disaster prevention by demonstrating comprehensive capabilities from observation to analysis, proposal of countermeasures, and design. In the civil engineering design department, we conduct surveys of the current state of existing retaining walls and evaluate their safety and integrity, as well as propose future countermeasures. Additionally, we design slope inspections and safety measures in road disaster prevention design (public works), and conduct safety evaluations of steep slopes specifically in the construction field, as well as design slope disaster prevention measures. ■Survey Contents - Slope disasters - Soft ground technology analysis - Integrity surveys of existing retaining walls *For more details, please download the PDF or contact us.

• Geological Survey Company

We contribute to solving global environmental issues towards the realization of a "sustainable" society where humans and nature can coexist, starting with investigations into ground environmental problems such as soil contamination and groundwater pollution. Please feel free to contact us if you have any requests. 【Survey Contents】 ■ Soil and Water Quality Contamination - Document research - Surface soil investigation (overview survey) - Depth direction investigation (boring survey) - Analysis of contamination mechanisms and consideration of purification measures ■ Groundwater Conservation ■ Vibration and Noise ■ Investigation of buried cultural properties and historical buildings ■ Investigations related to final disposal sites *For more details, please download the PDF or contact us.

• Geological Survey Company