Performance Evaluation of Permeable Pavement Systems

Transcription

1 Performance Evaluation of Permeable Pavement Systems 1 Civil and Environmental Eng., Pusan National University 2 Seoyeong Engineering Co., Ltd.

2 Performance Evaluation of Permeable Pavement Systems 1 Civil and Environmental Eng., Pusan National University 2 Seoyeong Engineering Co., Ltd.

3 Contents Introduction Element, Model and Prototype Scale Tests Element Scale Example - Permeability and Clogging Model Scale Example - Rainfall Infiltration / SWCC Back-Calculation Summary

4 Introduction

5 Introduction Nakdong River LID (

6 Introduction Nakdong River LID (

7 Introduction

8 Element Scale Test Variable Cement Concrete Mixture Design Korea (Ministry of Land, Infrastructure and Transport) Japan (Japan Road Institute) Non-Pervious Concrete Vehicle Road Pedestrian Road Flexural Strength 4.5 MPa 4.5 MPa 2.5 Mpa Permeability 0.01 cm/s 0.1 cm/s Porosity 15-20% 20-25% Permeable Block Design Korea (Seoul Metropolitan City) Japan (Interlocking Block Pavement Porous Block Interlocking Block Variable Technology Institute) Vehicle Road Pedestrian Road Vehicle Road Pedestrian Road Pedestrian Road Flexural Strength 5 Mpa 4 MPa 5 MPa 5 MPa 3 MPa Compressive Strength 20 MPa 16 MPa 20 MPa 20 MPa Permeability 0.01 cm/s 0.01 cm/s 0.01 cm/s 0.01 cm/s 0.01 cm/s

9 Element Scale Test Variable Korea Ministry of Land, Infrastructure and Transport Asphalt Concrete Mixture Design Permeable Friction Course Seoul Metropolitan City United States TxDOT (PFC-F) TxDOT (PFC-C) Permeable Pavement (Infiltration to Base) Japan (Japan Road Institute) Vehicle Road Pedestrian Road United States UNHSC Porosity 20±0.3% 20±1% 22% 18% ~ 20% 12% 16-22% Permeability 0.01 cm/s 0.01 cm/s 0.01 cm/s 0.01 cm/s Cantabro Loss 20% (20 ) 30% (-20 ) 20 % 20% 20% 20% Unaged 30% Aged Drain-Down 30% 10% 10% 30% Tensile Strength 85% 70% Retained (TSR) Wheel Tracking Test Overlay Tester Marshall Stability Flow Value 3000 cycles/mm 3000 cycles/mm ( 10,000 cycles/12.5mm, Hamburg Wheel Test) 200 cycles For Information For Information 3000 cycles/mm 5.0 kn 3.43 kn 3.0 kn (0.1mm)

10 Model Scale Test

11 Prototype Test

12 Prototype Test Pressure head observation Water quality sampling Underdrain effluent flux collection

13 Prototype Test

14 Element, Model and Prototype Scale Tests Test Scale Material Structural Hydrologic Element Pavement Cantabro Test Tensile Strength Reduced Drain-Down (Asphalt) Wheel Tracking (Asphalt) Marshall Stability (Asphalt) Dynamic Modulus (Asphalt) Flexural Strength (Concrete, Block) Compressive Strength (Concrete, Block) Porosity Permeability Clogging Soil-Water Characteristic Curve Aggregate & Soil Particle Size Distribution Maximum Unit Weight California Bearing Ratio Compression Test Resilient Modulus Cantabro Test (Aggregate) Porosity Permeability Soil-Water Characteristic Curve Test Scale Environmental & Thermal Hydrologic Model Prototype Contamination (Controlled) Contamination (Uncontrolled) Surface Temperature Bold may be used for design criteria Italic may not be equipped in Korean LID Research Center Infiltration Rainfall Infiltration Ponding Clogging Evapotranspiration Infiltration Rainfall Infiltration Ponding Evapotranspiration

15 Element Scale Test Permeability and Clogging Test Procedure - Clogging Sample setup Sample saturation h Heads adjustment Mixing Tank L Pavement Base Flow Meter Water flow for 10 mins Hold water flow Apply 40 g clogging particle Repeat until no more clogging applicable Brush clogging particle into pore End

16 Element Scale Test Permeability and Clogging Mixing Tank Tank Capacity: 200 L Mixer Speed: 5.5 rps Max Pump Capacity: 150 L/h Max Water can circulate into the tank using a bypass value

17 Element Scale Test Permeability and Clogging Stand Column Cross-Secion: 300x300 mm Three sections assembled Column Section Outlet valves at 150, 300, 600 mm for constant heads Overflow can circulate to mixing tank Pavement Section Height: 100, 150, 200 mm ㄱ, ㄴ shape assembled Aggregate Section Height can adjust up to 400mm

18 Element Scale Test Permeability and Clogging Flow Meter Tipping bucket 100, 200, 300 ml buckets Counter connected to data acquisition Calibration required

19 Element Scale Test Permeability and Clogging Test Material Pervious Concrete Mixing (KS F2425) - Mixer used with following proportion Compaction (KS F2043) Mixture proportions of the pervious concrete mixtures Pervious concrete No. Cement (kg/m 3 ) 3/8 aggregates 12.5~9.5 mm (kg/m 3 ) #8 aggregates 4.75~2.36mm (kg/m 3 ) Water (kg/m 3 ) Porosity Type A Type B

20 Element Scale Test Permeability and Clogging Test Material Base Size (mm) % Passing Water Content (%) Dry Density (g/cm 3 ) Relative Density (%) Volume (cm 3 ) Mass (kg) Clogging Particle Size (mm) Sieve No. #6 Silica Sand 0.25~0.6 30~60 #8 Silica Sand 0.075~ ~200

21 Element Scale Test Permeability and Clogging Permeability No Clogging Pervious Concrete (Type A) Base Pervious Concrete (Type A) + Base Permeability Clogging Pervious Concrete (Type A) with Clogging Sand #6 Pervious Concrete (Type A) with Clogging Sand #8 Pervious Concrete (Type B) with Clogging Sand #6 Pervious Concrete (Type B) with Clogging Sand #8

22 v (cm/s) v (cm/s) Element Scale Test Permeability and Clogging Permeability No Clogging Pervious Concrete (Type A) 1 y = x R² = i (cm/cm) Base Pervious Concrete (Type A) v = ki n v = 0.246i n = 0.72 k = (cm/s) Base y = x R² = v = ki n v = 0.066i i (cm/cm) n = 0.80 k = (cm/s)

23 v(cm/s) Element Scale Test Permeability and Clogging Permeability No Clogging Pervious Concrete + Base 1 y = x R² = i(cm/cm) Pervious Concrete + Base v = ki n v = 0.072i 0.74 n = 0.74 k = (cm/s) n k Pervious Concrete Base Pervious Concrete + Base

24 Volume of flow (L) Volume of flow (L) Element Scale Test Permeability and Clogging Permeability - Clogging no clogging 40 g clogged 80 g clogged 120 g clogged 160 g clogged 200 g clogged Type A Clogged with #6 Sand Clogged Sediment k (cm/s) No clogging g g Time (s) no clogging 40 g clogged 80 g clogged 120 g clogged 160 g clogged 200 g clogged 240 g clogged 120 g g g Type A Clogged with #8 Sand Clogged Sediment k (cm/s) No clogging g g g g Time (s) 200 g g

25 Volume of flow (L) Volume of flow (L) Element Scale Test Permeability and Clogging Permeability - Clogging 5 no clogging 40 g clogged 80 g clogged 120 g clogged Type B Clogged with #6 Sand Clogged Sediment k (cm/s) No clogging g g g Time (s) no clogging 40 g clogged 80 g clogged 120 g clogged 160 g clogged Type B Clogged with #8 Sand Clogged Sediment K (cm/s) No clogging g g g Time (s) 160 g

26 5. 시험결과 Element Scale Test Permeability and Clogging Permeability - Clogging k/k initial k/k initial Type A with #8 Type A with # Amount of clogging particle (g) Type B with #8 Type B with # Amount of clogging particle (g) More sediments are clogged in the concrete with larger pore. When the same amount of sediments are applied, #6 sand tends to reduce permeability more.

27 Model Scale Test Rainfall Infiltration Pavement Permeameter Upper Section Lower Section Counter Data Logger Tipping Bucket Lysimeter

28 Model Scale Test Rainfall Infiltration Upper Section Lower Section For pavement section of height 10, 15 and 20 cm Dimensions: 30x30x15 cm, x20 cm, x25 cm Values 5 cm below the top for runoff ㄱ, ㄴ shape to assemble pavement For base layer Drainage at the bottom

29 Model Scale Test Rainfall Infiltration Bottom Support Lysimeter Accommodate base section up to 40 cm Geotextile layered Record evapotranspiration Load Cell Capacity: 300 kg Load Cell Resolution: 0.01 kg Waterproof roof

30 Model Scale Test Railfall Infiltration Tipping Bucket Counter Data Logger Measure flow rate 100, 200, 500 ml buckets

31 Model Scale Test Infiltration Material Pervious Concrete 40 mm Aggregate Well-Graded Size (mm) % Passing Dimensions: 30x30x40 cm 90% Relative Compaction Compacted in two layers (20 cm each) Weight: 72kg 40 mm Aggregate Uniform Size (mm) Dimensions: 30x30x10 cm Compaction following KS F 2043 Weight: 17.64kg Unit Weight: kn/m 3 % Passing Dimensions: 30x30x40 cm Compacted in four layers (10 cm each) Weight: 72kg

32 Model Scale Test Rainfall Infiltration Test Procedure Mobile Rainfall Simulator Pavement Permeameter Compact base layer Assemble and setup pavement layer Adjust and calibrate rainfall intensity Setup permeameter and rainfall simulator Spray water and measure runoff and drainage

33 Model Scale Test Rainfall Infiltration Test Results Infiltration to Pervious Concrete + Base Rainfall Intensity: 148 mm/hr Duration: 3600 s Well-Graded Base Uniform Base

34 Model Scale Test SWCC Back-Calculation Van Genuchten-Mualem Model (Van Genuchten, 1980; Mualem, 1976) Soil-Water Characteristics Curve θ h = θ r + θ s θ r [1+ΙαhΙ n ] m h < 0 θ s h 0 θ r = residual water content θ s = saturated water content (or porosity) α = suction head at air entry (α > 0) n = coefficient regarding pore size distribution (n > 1) m = 1 1/n h = suction head Relative Permeability Function K h = K s S l e[1 (1 S e l/m ) m ] 2 K s = saturated permeability S e = effective degree of saturation = θ h θ r /[θ s θ r ] l = coefficient regarding connectivity of pore = 0.5 for geotechnical material

35 Model Scale Test SWCC Back-Calculation Pervious Concrete Dimensions: 30x30x20 cm Weight: 34.5 kg Mixed for construction (The GL, 2015) Parameter Value Source K s cm/s Lab Test θ s Lab Test θ r Kim et al. (2015) l 0.5 Mualem (1976) α Unknown Inverse Analysis n Unknown Inverse Analysis

36 Model Scale Test SWCC Back-Calculation Constant Head Test Porosity k = L h Q A(t 2 t 1 ) h = head difference (= 20 cm) Q = volume of flow t = duration (= 600 s) k = permeability = cm/s Parameter Value Source K s cm/s Lab Test θ s Lab Test θ r Kim et al. (2015) l 0.5 Mualem (1976) α Unknown Inverse Analysis n Unknown Inverse Analysis Montes et al. (2005), Ahn et al. (2013) P % = 1 W D W s γ w V T ( 100%) w D = dry weight w s = submerged weight V T = total volume r w = unit weight of water P = 21.6%

37 Model Scale Test SWCC Back-Calculation Unknown System Model α (n) and n (n) Finite Element Model HYDRUS 2D (PC-Progress, 2011) UNKNOWN SYSTEM Drainage Measured Drainage Calculated MODEL α (n+1) and n (n+1) PARAMETER ADJUSTMENT ALGORITHM Parameter Value Source K s cm/s Lab Test θ s Lab Test θ r Kim et al. (2015) l 0.5 Mualem (1976) α Unknown Inverse Analysis n Unknown Inverse Analysis Error minimized? Yes PARAMETER DETERMINATION No

38 Model Scale Test SWCC Back-Calculation Model Test Results Test Case Rainfall Intensity: 136 mm/hr Duration: 1400 s (23 min) Measured and Calculated Drainage for Inverse Analysis Parameter Value Source K s cm/s Lab Test θ s Lab Test θ r Kim et al. (2015) l 0.5 Mualem (1976) α 3.69 Inverse Analysis n 4.42 Inverse Analysis α = 3.69 and n = 4.42 estimated

39 Model Scale Test SWCC Back-Calculation Soil-Water Characteristics Curve of Pervious Concrete Soil-Water Characteristics Curve of Soils (Schanz, 2007)

40 Summary A test program and facility with scales of element, model and prototype experiments is under development. Equipment for infiltration and permeability, considering clogging, of permeable pavement systems is developed and being tested. Soil-Water Characteristic Curve of a pervious concrete sample was successfully back-calculated based on rainfall infiltration model test.

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