Geology

With professional investigation team, HEC has undertaken almost of geologic investigation of water resources sector and a part of this of other sectors, besides, HEC has carried out investigation contracts in Laos, Cambodia, etc.
Professional field:

• Geologic investigation for new construction of all structures (in all grades and design stages) in following fields: water resources and rural development, hydropower, building, transportation, industry, marine work and other civil structures.
• Geologic investigation for quality control, assessment of actual status for repair and upgrade of existing structures in all fields mentioned above.
• Preparation of tender documents, required documents, participation in bidding evaluation, preparation of bidding documents, participation in bidding, project management of geologic investigation works.
• Supervision, appraisal, review, control, participation in scientific research subjects and establishment of standards and regulations in engineering geologic investigation field.
• Instruction of technological transfer, human force training in engineering geologic investigation.

Technology in engineering geologic investigation:

• Implementing fully and entirely all steps in engineering geologic investigation chain, including: preparation of outline, cost estimation; Investigation and field testing; Laboratory testing; Preparation of report; Supervision during project construction. Explaining, reporting and working with concerned agencies about geologic investigation work during investigation, construction and operation of the project.
• Implementing fully all technologies in geologic investigation and document preparation including:

o Field investigation:

 Mapping and measurement of engineering geologic conditions, actual status of foundation pit, actual status of works. Geologic mapping and measurement and finding construction materials such as soil, rock, sand and gravel, etc. Establishment of maps of engineering geologic conditions, actual status of foundation pit, of works with small to large scales.
 Investigation, assessment of seismic, faults and new tectonic activities for new construction, repair and upgrading of existing works.
 Geophysical investigation by combination of measures including electric measurement (sound measurement, profile measurement, dipole axis, etc.), seismic measurement (measurement of oscillation by hammer, blast), magnetic measurement, etc.
 Geologic investigation with test holes including drill hole, auger hole, excavated hole, excavated trench, static penetration, etc.
 Field testing at test hole includes: hydrogeologic testing (water pour-in, water intake, water pour-out, water level observation, etc.).
 Dynamic penetration test, standard penetration test, shear test, measurement of wave along borehole, etc.
 Testing in horizontal tunnel, vertical well, horizontal compression test and slide test, etc.
 Field compacted test, earthfill quality test, reinforced concrete quality test, sand, gravel, rock, soil material quality test.
 Laboratory test:
 Laboratory test for foundation samples and construction material sample including soil, rock, sand, gravel and water, etc.
 Carrying out tests for determination of physical, mechanical, chemical and special characteristics (expansion, contraction, disintegration, salt content, etc.) of all samples with national and international standards.

o Preparation of engineering geologic documents:

 Preparation of general assessment report, specialized assessment reports on engineering geologic conditions, hydrogeologic conditions, actual status and proposal of treatment measures for foundation, materials during design, construction and operation of works.
 Providing parameters of characteristics of foundation and construction materials as required by design for new construction and repair, upgrading of existing works.
 Establishment of engineering geologic maps, hydrogeologic maps, map of actual status of foundation pit, actual status of works, map of layer face, actual map, map of construction materials, etc as required.
 Establishment of geologic sections, engineering geologic sections, hydrogeologic sections, foundation and body section of work actual status, sections for estimation of construction material reserves.
 Synthesizing physical, mechanical and chemical characteristics of soil, rock, sand, gravel of foundation and construction materials for design and new construction as well as repair and upgrading existing works.
 Preparation of borehole documents of engineering geologic, hydrogeologic investigation including borehole log, drillcore log, crack diagram, geophysical measurement results, field and laboratory testing results, pictures of drillcore samples and geologic mapping and measurement documents, etc.

Typical projects:

• Large scale reservoirs include: Cua Dat (in Thanh Hoa province), Ngan Truoi (in Ha Tinh province), Ta Trach (in Thua Thien Hue province), Dinh Binh (in Binh Dinh province), Tan My (in Ninh Thuan province), Lower Krongbuk, Upper EaSoup (in Dak Lak province), Nam Say Mun, Nam Cheng (in Laos), etc.
• Large pumping stations include: Phu Sa (in Hanoi city), Tan Chi (in Bac Ninh province), Khai Thai, Van Dinh (in Hanoi city), Lac Trang, Yen Lenh (in Ha Nam province), Gia Vien (in Ninh Binh province), Linh Cam (in Ha Tinh province), Dong Pho Sy, Tha Pha Nong Phong (in Laos).
• Hanoi dike, Red river embankment, Da river embankment, Sai Gon river surrounding dike, etc.
• Irrigation systems include: Bai Thuong, Do Luong, Cau river, Ke Go, Nam Dan, Ngan Truoi - Cam Trang, etc.
• Hydropower projects include: Thac Ba, Thac Bay, Cho river, Phu Ninh, BuonTaurah, Dinh Binh, Cua Dat, Khe Dien, Nam Dong, Krong H’nang, Pha Lai thermal power, etc.
• Civil works include: Hanoi city complex, Deawoo Building (in Hanoi), Hue Central Hospital (in Thua Thien Hue province), etc.
• Industrial works include: Ha Tay Beer Factory, Bim Son Cement Factory, Dung Quat Industrial Zone, etc.
• Transportation works include: Doc Xay Tunnel (in Thanh Hoa province), access roads of hydraulic, hydropower projects, traffic bridges, railways in hydraulic, hydropower projects, etc.
• Marine works: Xuan Hai sea embankment (in Phu Yen province).
• Repaired, upgraded irrigation systems include: Muc river (in Thanh Hoa province), Bac Hung Hai, 5 pumping stations of Nam Ha system, Tuyen Lam reservoir (in Da Lat city), Chu river irrigation system (in Thanh Hoa province), North Nghe An irrigation system (in Nghe An province), etc.
For detail, see in Project.

Equipment for geologic investigation work:

• Equipment for geophysical investigation: unipolar, multipolar electric meter using 1D, 2D method. 1-current, 12-current, 24-current seismic measurement device. Magnetic, wave measurement device for electric exciter, transmission cable, specialized receiver. Equipment made by Vietnam, USA and Western countries. Specialized data processing software enclosed with geophysical equipment including VES4, Image, Res2Dinv (electric measurement) SeisImager and Knox (seismic measurement).
• Driller: XY1, XY1A, Long year, Tone, Koken, B53, GX1T with diamond, alloy auger with diameter of 42mm, 250mm, vertical drilling depth of 300m, inclined drilling with angle of 90o with depth of 50m. The worker team has high skill level from 4/7 to 7/7.
• Specialized sample collecting device for rock (single barrel, double barrel, three barrel), for weak soil (thin wall tube, piston tube), for sand and gravel (basket tube, tube in SPT device).
• Auger drilling.
• Semi-automatic and automatic static penetration device.
• Field testing: specialized devices (flow bucket, pump, meter, stopper with pressure resistance up to 50 Kg/cm2 for hydrogeologic testing (water pour-in, water intake, water pour-out, water level observation, etc.).
• Specialized equipment made by Vietnam, USA, UK, Japan, South Korea, etc for dynamic, standard penetration testing, shear testing.
• Specialized equipment for testing in horizontal tunnel, vertical well, horizontal compacted testing and slide testing.
• Specialized equipment for field compacted testing, earthfill, soil, rock, sand and gravel quality check testing.
• Supersonic measurement device, rebound gun, reinforced concrete measurement device, etc for reinforced concrete quality check.

o Laboratory testing:

 LAS standard laboratory granted by Ministry of Construction.
 Laboratory testing uses specialized devices include automatic and semi-automatic recording devices.
 Testing workers have high skill level (3/7, 7/7) and engineers have 5 - 25 years of experience.

o Preparation of engineering geologic documents:

 Using copyrighted software including Autocad, Microsoft office, Roclab, Dip, etc., specialized software set up by HEC including GP2000 (for setting up geologic section), SP2004 (for criteria synthesis), software for setting up borehole documents, field testing data analysis software, software for formation of appendices, tables in report, etc.
 Preparation of engineering geologic investigation and hydrogeologic investigation reports done by engineers with over 10 years of experience meeting Vietnamese and international standards such as BS, ASTM, etc.