Geological Exploration: Issues and Countermeasures

Geological exploration is a crucial component in construction engineering, and the accuracy of the exploration results significantly impacts the construction project. Therefore, it is essential to conduct thorough geological exploration work. This article primarily discusses some of the issues present in geotechnical engineering geological exploration and summarizes the corresponding technical measures, providing a reference for ensuring the quality of construction projects.

As a major component of construction, geotechnical exploration is subject to increasingly stringent standards. During the exploration process, it is required to accurately reflect the geological conditions of the site, identify geological hazards, conduct thorough exploration, and submit correctly evaluated, comprehensive, and cost-effective exploration data, ensuring the safety of the project quality and enhancing the investment benefits of the project.

1. Main Methods and Techniques of Engineering Geological Exploration

The primary objective of geotechnical investigation is to ascertain and assess the geological and geotechnical conditions of the construction site and foundation, and to understand the potential interactions between geological conditions and construction activities. This involves exploration, testing, and inspection work, followed by the analysis, calculation, and evaluation of various data obtained for use in engineering. Based on this foundation, scientific and efficient schemes for geotechnical utilization, modification, reinforcement, and design benchmarks and parameters are developed, all of which are referred to as proposal recommendations. Among all engineering geological surveys, geotechnical engineering is the most comprehensive, employing a range of technical methods including engineering geological mapping, exploration sampling, in situ testing, and on-site inspection and monitoring.

The foundational aspect of geotechnical investigation work is engineering geological mapping, which is typically completed at the initial stage of the survey. For projects with complex topography and geological conditions, it is necessary to conduct engineering geological mapping. Understanding the geological conditions of the construction site through engineering geological mapping is the most scientific and rational approach, providing a solid basis for other surveying methods.

During exploration activities, techniques such as geophysical prospecting, drilling, and trenching are primarily used. These techniques are applied for the investigation of subsurface geological conditions and can also be utilized for sampling to carry out in situ tests and monitoring. The most suitable exploration technique should be selected in conjunction with the survey objectives and the characteristics of the geotechnical materials. Drilling and trenching, also known as exploration engineering, are direct exploration methods that accurately reveal geological conditions and are frequently used in geotechnical investigation work. Among these, drilling is more widely used and can be flexibly selected based on different soil strata and survey requirements. If drilling methods cannot clarify the geological conditions, trenching methods must be employed.

Geophysical prospecting is an indirect exploration method, which, compared to drilling and trenching, has the advantages of being less invasive and faster. If accurate calculations cannot be made during geological mapping and the construction timeline is tight, this method is highly efficient and is generally combined with geological mapping. It can also provide a good basis for drilling and trenching. However, the results of geophysical prospecting are often not unique and are significantly constrained by geological conditions, thus requiring the application of exploration engineering experience to interpret the findings.

2. Issues in Geotechnical Geological Exploration Process

2.1 Lack of Rationality in Design and Execution of Exploration Work

During geotechnical exploration, it is common for exploration to be conducted without following standard requirements, leading to issues such as excessive spacing between exploration points and insufficient hole depths. Sometimes, problems arise that cause the designed exploration work to not match the actual conditions, preventing a detailed examination and resulting in certain design flaws.

2.2 Lack of Innovation in Exploration Techniques and Technology

In recent years, although there has been some development in geotechnical exploration in China, the overall technical level remains relatively low, and there is a lack of innovation in exploration technology, which has affected the economic benefits and development of geotechnical exploration. In actual exploration processes, issues such as low-quality data obtained during sampling, limited application range of exploration methods, and insufficient analysis of parameters like foundation bearing capacity are common. While exploration work can meet basic standards, traditional techniques have become relatively outdated with the continuous development of society. Therefore, to promote new developments in geotechnical exploration technology, it is necessary to explore modern exploration methods.

2.3 Human Factors Leading to Discrepancies Between Actual Conditions and Exploration Results

During geotechnical engineering exploration, a high level of technical expertise is required of the exploration personnel. However, in actual exploration processes, due to the relative lack of practical experience and knowledge among some exploration personnel, there are often discrepancies between actual data and design data. Additionally, some companies, due to financial constraints, may hire personnel who do not meet the standards for exploration work to save costs, resulting in exploration findings that significantly deviate from the actual results.

2.4 Use of Outdated Exploration Equipment

Advanced exploration equipment is an important factor in ensuring the accuracy of exploration results. In past exploration processes, due to the use of outdated exploration technology, there were significant exploration issues, preventing accurate and comprehensive geotechnical engineering exploration. For example, sometimes the use of older software resulted in issues such as poor conversion and incomplete functionality, leading to insufficient exploration findings.

3. Methods to Improve Exploration Quality

3.1 Training

Regular education and training for exploration technical personnel should be conducted, especially for those with more seniority whose knowledge may be outdated. When using new technologies and equipment, they may find it difficult to adapt. In such cases, companies should hold specialized technical training to improve the knowledge level of technical personnel. To allow different professional knowledge and technologies to permeate the exploration work, companies can implement an internal job rotation system to maximize the depth and breadth of the exploration personnel’s knowledge.

3.2 Increase the importance of On Site Testing and Geotechnical Sampling

During the geotechnical exploration process, in situ testing and sampling of the soil and rock provide test data, which are the main reference materials for solving technical problems in geotechnical engineering exploration. Since test data are the premise for evaluation and analysis, without ensuring the applicability, reliability, and completeness of the test data, all evaluation and analysis work would lack a foundation. In the geotechnical engineering exploration process, the calculation parameters and modulus of the soil and rock engineering determine the reliability and accuracy of the calculations. Moreover, due to the high difficulty of geotechnical engineering testing, the test results can vary significantly under the influence of external environmental factors during sample preparation and drilling for sampling.

3.3 Regulate Market Management

It is essential to focus on inspecting whether exploration-related units hire exploration personnel who do not meet the technical standards. Units found to have such situations should be severely penalized. Additionally, a comprehensive legal system should be established to enhance the supervision of enterprises and units, ensuring control over exploration efficiency and quality. Each exploration unit should thoroughly analyze exploration reports, examine the site’s foundation selection, stability, and other aspects, and conduct checks on related analysis data and conclusions. This prevents reputational and economic losses due to substandard technical personnel levels, improves market regulation and management, ensures consumer rights, prevents contract disputes, promotes enterprise reform, and accelerates the development