The general exploration gives information about which of the following features?

Question

Examoogle · Accepted Answer

Option D: All of the mentioned

Explanation & Concepts:
General exploration (or preliminary site investigation) is the initial phase of soil investigation aimed at determining the broad geological and geotechnical features of a site. It provides essential data regarding the stratification of soil, depth to bedrock, and the location of the water table, which are critical for the preliminary design of foundations.

Working Principle: The process involves conducting a reconnaissance survey, studying existing geological maps, and performing simple field tests like wash borings or geophysical methods (seismic refraction/electrical resistivity). These techniques identify the spatial variability of soil layers and detect anomalies, allowing engineers to decide the depth and type of detailed boring required for the final design.

Key Formulas: $d_c = \frac{1}{2} \sqrt{\frac{q_u}{\gamma}}$ — Empirical approximation for preliminary investigation depth in specific strata

Key Points: General exploration is conducted before detailed subsurface investigation.; It helps in selecting the method of boring and the number of boreholes.; It assists in identifying potential hazards like sinkholes, high water tables, or boulders.; The scope is typically limited to a rapid assessment of site feasibility.

Advantages: Reduces the risk of encountering unexpected ground conditions.; Cost-effective for preliminary design phases.

Disadvantages: Does not provide detailed soil strength parameters.; Limited accuracy in highly heterogeneous ground conditions.

Applications: Foundation site selection; Preliminary bridge alignment studies; Dam site feasibility assessment

Additional Info: Standard procedure follows IS 1892 for subsurface investigation in India.. General exploration is often supplemented by geophysical methods to reduce drilling costs.

Answer: D is correct — General exploration aims to map the overall geological and hydrological characteristics of a site, encompassing soil strata, rock depth, and groundwater levels.

Exam Tip: Always remember that in Civil Engineering, site investigation is a hierarchical process starting from general reconnaissance and moving toward detailed field and laboratory testing.

Examoogle · Answer

Option A: Depth of rock

Examoogle · Answer

Option B: Composition of soil strata

Examoogle · Answer

Option C: Ground water level

Correct Answer

Discussion (0)

Correct Answer

Related Questions

Discussion (0)