Hydraulic Conductivity Chapter 6 Bernoulis Equation piezometer - PDF document

2/25/2015 Hydraulic Conductivity Chapter 6 Bernouli’s Equation piezometer ∆� � � � hydraulic gradient 1

2/25/2015 Flow Regimes Darcy’s k Law 1 Seepage Velocity 2

2/25/2015 Seepage Velocity � � �� � � � � � � � � � � � � � � � � 1 � � � � � � � � � � � � � � � 1 � � � Hydraulic Conductivity 3

2/25/2015 Hydraulic Conductivity Degree of Saturation Absolute Permeability Hydraulic Conductivity Absolute Permeability (Soil / Water Property) (Soil Property Only) �  � � � � �  ��  �� � � � � � � � � �� � � � �� 4

2/25/2015 Viscosity of Water Source: www.ce.texas.edu Density of Water Source: www.ce.texas.edu 5

2/25/2015 Hydraulic Conductivity Soil / Water Property Soil Property �  � � � � �  ��  �� � � � � � � � � �� � � � ��  � � � � � � � �  � � � Hydraulic Conductivity 6

2/25/2015 Constant Head Test � � �� ��� Falling Head Test � � 2.303 �� � � �� log �� � � 7

2/25/2015 Example � � �� ��� � � �� � � � � � � � � 1 � � � Example � � 2.303 �� � � �� log �� � � 8

2/25/2015 Example � � � � � � �� � → � � � � � Density of Water 25  C Source: www.ce.texas.edu 9

2/25/2015 Well Pumping Well Pumping 10

2/25/2015 Example A 200 ‐ mm ‐ diameter well that fully penetrates a 25 ‐ m ‐ thick confined aquifer is pumped at a rate of 2000 m 3 /day. The drawdown in an observation well 100 m away is 1.4 m and the drawdown in an observation well 50 m away is 4 m. What is the horizontal permeability of the aquifer? Drawdown q s h 0 h 11

2/25/2015 Example What would be the horizontal permeability of the aquifer if it was unconfined instead? Assume the static water level in the aquifer is 100 m above the impervious layer. Drawdown q s h 0 = 100 m h 12