Engineering Geology Flashcards
What are five geological factors affecting engineering practice?
Direction of planar features, Water table height, Grade of weathering, Joint density, Joint or fracture continuity
Define Rock Head
The boundary between solid rock and overlying unconsolidated sediment
What are three geological hazards associated with tunnels?
Gas build up, Flooding of tunnels due to permeable rock or burst pipe, Rock fall
What are four ways to reduce hazards in tunnels?
Shotcrete, Ring structure, Arch structure, Drains
What are five mitigation techniques to reduce damage to buildings from swelling and shrinking of clay?
Deep foundations below the water table, Continuous reinforced raft foundation, Effective drainage systems, Artificially lower the water table, Remove trees
What three rocks are usually associated with producing radon gas?
Granite, Limestone high in uranium, Dark organic rich mudstone
What are four hazards of radon gas?
It is radioactive, No taste, smell or colour, Soluble in water, Can damage cells in lungs leading to cancer
How does radon gas migrate from the rock to the surface?
Dissolves in water and gets carried to the surface, Diffuses through rock
What are three things which can be installed in homes to ensure low levels of radon gas are maintained?
Ventilation, Impermeable membrane under the house, Extractor fan
Define Brownfield Site
Areas that have been used previously by industry or commerce and are now derelict
What are three problems of brownfield sites?
Sites are contaminated by chemicals or hazardous waste, Groundwater contamination, Contaminated vegetables
What are the four stages of clean up of a brownfield site?
(1) Preliminary site investigation - desk research (2) Intrusive site investigation - borehole, risk assessment (3) Remediation works - fix it (4) Verification and validation - check to see if it worked
What are three methods to remediate a brownfield site?
Phytoremediation, Stabilisation and solidification, Groundwater treatment
