Home > Exhibition > Content
Drilling process and drilling log
Jun 28, 2017

Drilling process

1.drilling method should ensure accurate formation of different formations, no leakage layer, different strata stratification error should not be more than + 0.1m. The soft layer, special thin layer and fracture zone, should be strictly controlled to footage. The core must be loaded into the core box in a separate format, placed neatly according to its actual location in the borehole, and no core section shall be vacated. Corresponding to the back and layering must be affixed to the label, sub box number, mark the upper and lower core after taking pictures, photos corresponding number. No core shall be damaged or discarded without the consent of the geological engineer. 2, the hole diameter to meet the test and debris samples taken as the principle, general provisions adopted hole diameter of rock specimens is not less than 91mm diameter, test the hole diameter should be greater than the diameter of the probe level test. 3, drilling depth of maximum allowable deviation is about 2 per thousand, drilling verticality: no more than 1.5 degrees, the level measurement in the drilling process. 4. The original records of the drilling shall be recorded accurately and in detail according to the requirements, and each return shall be described and shall not be recorded after the event or recorded in the same stratigraphic record. The drilling parameters and drilling conditions shall be recorded in detail, such as drilling pressure, speed, pump volume, flushing fluid, water leakage in the hole, water gushing, sand bursting, hole collapsing, drilling tool vibration, drilling method, accident in the hole, etc.. Core must be described in detail, with special attention to the description of the soft layer, inclusion, fracture zone characteristics, level, joint surface, corrosion, etc., and record the leakage of the flushing fluid in a timely manner. 5. Simple hydrogeological observation must be carried out according to relevant requirements during drilling. The water level changes shall be recorded 1~2 times per shift. In case of confined water, the height of water level shall be measured, and the initial water level and the stable water level shall be measured at each hole. 6, test: drilling hole drilling process, according to the requirements of the task book, the standard penetration test of silt and sand soil, spacing of 1 ~ 2.0m, and proper preservation of specimen; dynamic penetration test of gravel soil, gravel soil, weathered rock, weathered layer, general layered test. The probability of seismic liquefaction of saturated silt and sandy soil in earthquake area should be determined. In a span of more than 64M should be the abutment shear wave velocity test, according to test requirements of exploration holes should be drilled to the depth of design. 7, drilling situation and progress timely feedback to geological personnel, found that abnormal circumstances should be recorded and promptly dealt with.

Drilling log

1, drilling records must be in accordance with the prescribed format, by the record clerk on the spot to fill in in time, the record number must be accurate, the writing should be clear, data should be complete. If the timing error, should take off after the next line typo rewrite, shall not be altered, or re patching tear copy. 2, for each back records should include: the changes of circulating drilling footage and stability and water penetration such as color, liquid leakage and drilling core description. Specification for geotechnical classification standards for Railway Engineering (TB10077-2001). The core shall be described in detail in accordance with the requirements of different formations. Clay: name, color, structure and properties, and inclusion content, moisture level; sand soil: name, color, particle composition, particle size, particle composition and shape, density, moisture level, SPT counts; gravel soil: name, color, composition, particle size composition the degree of weathering, and particle roundness, filling composition and properties and content, compactness, weathering degree, dynamic penetration number; rock: name, color, structure, mineral composition, crack growth degree and crack size and filling degree, RQD (RQD = 10cm is greater than the cumulative length of time back to the core the footage, * 100%) weathering degree, cementation and dissolution. In case of karst cave, the depth and elevation of the top and bottom of the cave should be described in detail. The filling conditions in the karst cave, such as full filling, semi filling and no filling, should be described in detail, such as the color and state of the filling and inclusion. 3, when leveling machines, such as changes in the level of the hole, must be clearly marked on the original record. 4 、 standard penetration and dynamic exploration test shall be recorded in accordance with the prescribed form. 5, after the end of the hole should promptly collate drilling logs and statements, signature, according to the requirements of the geological team.

Products List