UVM Theses and Dissertations
Format:
Print
Author:
Syrrakou, Christina
Title:
Dept./Program:
Civil and Environmental Engineering
Year:
2014
Degree:
PhD
Abstract:
The recent expansion of impervious areas as a resul.t of urbanization and industrial advances is responsible for the increase in stormwater runoff, deterioration of water quality and depletion of the groundwater. As a solution to these problems the EPA has suggested the use of porous pavements. To date, existing research has provided valuable knowledge regarding stormwater runoff reduction as a result of application of pervious concrete systems. However, little information is known on the impact of such a system on the local groundwater table, which is crucial information for the hydrologic cycle.
This research aims at investigating the interaction between pervious concrete use and local hydrology using observations from a real pervious concrete site located in the town of Randolph, Vermont, USA. The tools that are used in conjunction with the field observations are laboratory experiments and a mathematical model, which is able to simulate flow of water through the pervious concrete system together with groundwater recharge.
Field observations and results from additional laboratory testing (including analysis of slug tests, grain size distribution and water retention data) show that the Randolph site has unique hydrogeologic conditions and, together with the cold Vermont climate, presents a challenging environment where pervious concrete use can be evaluated. The soil located in the area under study is predominantly composed of dense till deposits of low permeability and artesian wells exist on-site. A small-scale laboratory experiment was used to approximate evaporation rates in the pervious concrete system.
Additional testing included a controlled water release experiment on-site which resulted in a counterintuitive drop of the groundwater table in response to recharge reaching up to 4 ft. Comparison to groundwater level data observed in the same locations during the time that Tropical Storm Irene reached Vermont showed that the counterintuitive response was unique to the water release event.
Finally, a mathematical model that was used to simulate local flow conditions at the Randolph site is presented. The core model is a three-dimensional groundwater flow and contaminant transport model called the Vermont Variably-Saturated Transport Code (VTC). The model was extended by incorporating the ability to simulate vertical flow of water through the pervious concrete and crushed stone material while taking into account evaporation. The model was calibrated against data from Tropical Storm Irene and additional exploratory simulaton scenarios were investigated.
This research aims at investigating the interaction between pervious concrete use and local hydrology using observations from a real pervious concrete site located in the town of Randolph, Vermont, USA. The tools that are used in conjunction with the field observations are laboratory experiments and a mathematical model, which is able to simulate flow of water through the pervious concrete system together with groundwater recharge.
Field observations and results from additional laboratory testing (including analysis of slug tests, grain size distribution and water retention data) show that the Randolph site has unique hydrogeologic conditions and, together with the cold Vermont climate, presents a challenging environment where pervious concrete use can be evaluated. The soil located in the area under study is predominantly composed of dense till deposits of low permeability and artesian wells exist on-site. A small-scale laboratory experiment was used to approximate evaporation rates in the pervious concrete system.
Additional testing included a controlled water release experiment on-site which resulted in a counterintuitive drop of the groundwater table in response to recharge reaching up to 4 ft. Comparison to groundwater level data observed in the same locations during the time that Tropical Storm Irene reached Vermont showed that the counterintuitive response was unique to the water release event.
Finally, a mathematical model that was used to simulate local flow conditions at the Randolph site is presented. The core model is a three-dimensional groundwater flow and contaminant transport model called the Vermont Variably-Saturated Transport Code (VTC). The model was extended by incorporating the ability to simulate vertical flow of water through the pervious concrete and crushed stone material while taking into account evaporation. The model was calibrated against data from Tropical Storm Irene and additional exploratory simulaton scenarios were investigated.