EVALUATING THE EFFICIENCY OF HOUSEHOLD STORMWATER DETENTION SYSTEM

This paper describes the evaluation of water storing capacity of a household stormwater detention system based on field data. Collection of field data is often sidelined due to the cost and human capital incurred. However, the true value of field data is demonstrated here by comparing the observed and design data. A field test is completed in a real-life terrace house, utilizing the house’s 95m2 side canopy as roof catchment and 4.40m x 4.70m car porch area to station a detention tank. Precast concrete modular units with 3.9m3 effective storage volume are assembled within the tank. Downpipe with 0.1m diameter is installed to connect the roof gutter to the detention tank; while pipeline with 0.05m diameter is installed as the outlet from tank to the house perimeter drain. The mentioned setup is subjected to actual rainfalls from December 2019 till February 2020 that corresponded with the peak of Northeast Monsoon season. Ten observed storm events with peak hourly total rainfall readings ranging from 22 to 48mm are selected for analysis. Rainfall and water level readings from the field test allow the derivation of roof runoff volume and detained water volume in the tank. It is found that the household stormwater detention system is able to capture about 50% of the roof runoff. However, the current setup is found to cause flooding for rainfall over 40mm. The flooding issue, however, is undetected by the design data that underestimated the water storing capacity. This is due to the use of uncommon precast concrete modular units that may not have its flow characteristics represented by existing formula and model. No matter how uncommon the modular units be, various types and forms of stormwater detention system are becoming the new normal in the industry and field test is the best tool to validate their performances.

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Case Study of Modular Pre-cast Concrete On-Site Stormwater Detention System during Monsoon Season in Southeast Asia

Applied Environmental Research ◽

10.35762/aer.2021.43.1.3 ◽

2020 ◽

pp. 28-40

Author(s):

Darren Y.S. Mah ◽

Johnny O.K. Ngu ◽

Rosmina A. Bustami ◽

Frederik J. Putuhena

Keyword(s):

Water Level ◽

Field Test ◽

Goodness Of Fit ◽

Monsoon Season ◽

Precast Concrete ◽

Computer Simulation Model ◽

Northeast Monsoon ◽

Storm Events ◽

Diameter Pipe ◽

Hourly Rainfall

On-site stormwater detention system within a residential property is meant for an environmental protection device that temporarily stores stormwater within the property lot to mitigate flash flood, particularly during rainy seasons brought by the northeast monsoon. A field test was constructed in a house’s car porch with a 4.40 m x 4.70 m x 0.45 m tank filled with precast-concrete modular units with an effective storage volume of 3.97 m3. The system received water from a 95 m2 house roof via 0.1 m diameter pipe, discharged water via 0.05 m diameter pipe. It had recorded six observed storm events coincided with the 2019/2020 monsoon season that consisted 20–50 mm peak hourly rainfall, 0.0007–0.0018 m3 s-1 inflow, 0.0005–0.0012 m3 s-1 outflow and 0.21–0.47 m water level. Another four historical storm events coincided with the monsoon from 2015–2017 were sourced to augment the analysis. A computer model developed using the storm water management model was calibrated and verified using the six observed events. The Kolmogorov-Smirnov goodness of fit tests between the observed and modelled cumulative distributions had produced 0.01–0.14 maximum vertical distances that were lower than the 0.41–0.68 critical values indicating close matches. As such, the calibrated and verified model was used to simulate the historical storm events with 40–50 mm peak hourly rainfall and produced 0.0010–0.0013 m3 s-1 inflow, 0.00072–0.00076 m3 s-1 outflow and 0.41–0.45 m water level. By combining the field test and computer simulation model, it was found the system was able to contain all stormwaters from northeast monsoon. However, it had a weakness which the system was approaching its maximum capacity once the peak hourly rainfall exceeded 45 mm. With such a procedure in place, improvement could be carried out.

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NURSERY TECHNIQUES WITH JUVENILE CORAL TROUT, Plectropomus leopardus WITH DIFFERENT TYPES OF FOOD

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v6i2.9013 ◽

2015 ◽

Vol 6 (2) ◽

Author(s):

Anak Agung Alit ◽

Ketut Maha Setiawati ◽

Tony Setia Dharma

Keyword(s):

Sea Water ◽

Survival Rates ◽

Critical Factor ◽

Water Volume ◽

Design Data ◽

Feeding Method ◽

Growth And Survival ◽

Coral Trout ◽

Juvenile Coral ◽

Trash Fish

ABSTRACT Feed management is a critical factor in the nursery activities because food serves as an energy for growth and survival rates. The study aimed to determine the best feeding to improve growth and survival rates. Cultured of coral trout grouper seeds were used for this research in 9 fiber tubs each of 0.8 tonnes of sea water volume with 3 treatments and 3 replicates. The feeding treatments were (a) commercial feeding pelle; (b) trash fish; and (c) feeding combinations (50% pellets and 50% trash fish). The initial length of coral trout grouper seeds were 3 cm long. The pellet used was a commercial pellet with dose of 5-10% biomass, while the trash fish was clupeid fish. Feeding times were twice a daya at 08:00 and 16:00 local time. A complete random design was used as an experiment design. Data was analysed using ANOVA and descriptive statistics. Water qualities during larva rearing included water temperature, pH, salinity, DO, ammonia, nitrite, and phosphate. The results showed that growth dan survical rates was significantly affected by combination feeding method (50% pellet and 50% trash fish) with growth rate of 0.08% cm/day and survival rate of 60.20±2.34%. Keywords: Feed, trash fish, juvenile coral trout grouper, growth, and survival.

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UV design: comparison of probabilistic and deterministic design approaches

Water Science & Technology ◽

10.2166/wst.1996.0682 ◽

1996 ◽

Vol 33 (10-11) ◽

pp. 251-260

Author(s):

George Tchobanoglous ◽

Frank Loge ◽

Jeannie Darby ◽

Marvin Devries

Keyword(s):

Field Test ◽

Test Data ◽

Empirical Model ◽

Field Data ◽

Probabilistic Approach ◽

Uv Disinfection ◽

Statistical Nature ◽

Deterministic And Probabilistic Approaches ◽

Design Comparison

Deterministic and probabilistic approaches to the design of ultraviolet (UV) disinfection systems are reviewed and discussed. Field data that must be collected to apply each method are identified. An empirical model to predict UV disinfection performance is presented and discussed. The advantage of the probabilistic approach is that the variability in the wastewater characteristics, the variability in the field test data, and the statistical nature of the discharge requirements are reflected in the in design of the UV system.

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How Accurately Do Structural Asymmetric First-Price Auction Estimates Represent True Valuations?

Journal of Econometric Methods ◽

10.1515/jem-2017-0001 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Kirill Chernomaz ◽

Hisayuki Yoshimoto

Keyword(s):

Field Data ◽

Empirical Studies ◽

Estimation Methods ◽

Auction Market ◽

True Value ◽

Statistical Equivalence ◽

Asymmetric Auction ◽

Price Auction ◽

Kolmogorov Smirnov ◽

Smirnov Test

AbstractStructural asymmetric first-price auction estimation methods have provided numerous empirical studies. However, due to the latent nature of underlying valuations, the accuracy of estimates is not feasibly testable with field data, a fact that could inhibit empirical auction market designs and applications based on structural estimates. To assess their accuracy, we provide an analysis of estimates derived from experimental asymmetric auction data, in which researchers observe valuations. We test the null of statistical equivalence between the estimated and true value distributions against the alternative of non-equivalence. When advanced models are used, the Modified Kolmogorov-Smirnov test fails to reject the distributional equivalence, supporting structural asymmetric auction estimations for auction market studies. In addition, recovered efficiencies have plus-minus 2.5 percent precision, compared to the true efficiencies.

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High Efficient Sediment-Transport Water Volume in High Sediment-Laden River

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.214.265 ◽

2011 ◽

Vol 214 ◽

pp. 265-270

Author(s):

Jun Yan ◽

Biao Liang ◽

Hui Cao ◽

Yu Hua Zhang

Keyword(s):

Sediment Transport ◽

Transport Process ◽

Field Data ◽

Yellow River ◽

Water Volume ◽

The Lower Yellow River ◽

Calculating Method ◽

High Efficient ◽

Xiaolangdi Reservoir ◽

High Sediment

Analyzed the sediment-transport process in high sediment-laden river, the new concept and calculating method for sediment-transport water volume are proposed. Based on field data of sediment and water volume in the Lower Yellow River from 1950 to 2000, the sediment-transport water volume and unit sediment-transport water volume in LYR are calculated. Meanwhile, relations between them and influencing factors are confirmed to calculate efficient sediment-transport water volume after construction of the Xiaolangdi reservoir.

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Estimating CPT Parameters at Unsampled Locations Based on Kriging Interpolation Method

Applied Sciences ◽

10.3390/app112311264 ◽

2021 ◽

Vol 11 (23) ◽

pp. 11264

Author(s):

Jinhao Liu ◽

Jinming Liu ◽

Zhongwei Li ◽

Xiaoyu Hou ◽

Guoliang Dai

Keyword(s):

Bearing Capacity ◽

Direct Method ◽

Precast Concrete ◽

Kriging Interpolation ◽

Soil Parameters ◽

Engineering Practice ◽

Kriging Method ◽

True Value ◽

Kriging Interpolation Method ◽

Geotechnical Investigations

The cone penetrometer test (CPT) has been widely used in geotechnical investigations. However, how to use the limited CPT data to reasonably predict the soil parameters of the unsampled regions remains a challenge. In the present study, we adopted the Kriging method to obtain the CPT data of an unsampled location in Adelaide, South Australia, based on the collected CPT data from six soundings around this location. Interpolation results showed that the trend of the estimated parameters is consistent with the trend of parameters of the surrounding points. From the Kriging interpolation result, we further carried out axial bearing capacity calculation of a precast concrete pile using the CPT-based direct method to verify the reliability of the method. The calculated bearing capacity of the pile is 99.6 kN which is very close to the true value of 102.8 kN. Our results demonstrated the effectiveness of the Kriging method in considering the soil spatial variability and predicting soil parameters, which is quite suitable for the application in engineering practice.

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Review of Historical Dam-Break Events and Laboratory Tests on Real Topography for the Validation of Numerical Models

Water ◽

10.3390/w13141968 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1968

Author(s):

Francesca Aureli ◽

Andrea Maranzoni ◽

Gabriella Petaccia

Keyword(s):

Field Test ◽

Field Data ◽

Flood Hazard ◽

Numerical Models ◽

Data Access ◽

Dam Break ◽

Physical Models ◽

Real Field ◽

Test Cases ◽

Validation Data

Dam break inundation mapping is essential for risk management and mitigation, emergency action planning, and potential consequences assessment. To quantify flood hazard associated with dam failures, flooding variables must be predicted by efficient and robust numerical models capable to effectively cope with the computational difficulties posed by complex flows on real topographies. Validation against real-field data of historical dam-breaks is extremely useful to verify models’ capabilities and accuracy. However, such catastrophic events are rather infrequent, and available data on the breaching mechanism and downstream flooding are usually inaccurate and incomplete. Nevertheless, in some cases, real-field data collected after the event (mainly breach size, maximum water depths and flood wave arrival times at selected locations, water marks, and extent of flooded areas) are adequate to set up valuable and significant test cases, provided that all other data required to perform numerical simulations are available (mainly topographic data of the floodable area and input parameters defining the dam-break scenario). This paper provides a review of the historical dam-break events for which real-field datasets useful for validation purposes can be retrieved in the literature. The resulting real-field test cases are divided into well-documented test cases, for which extensive and complete data are already available, and cases with partial or inaccurate datasets. Type and quality of the available data are specified for each case. Finally, validation data provided by dam-break studies on physical models reproducing real topographies are presented and discussed. This review aims at helping dam-break modelers: (a) to select the most suitable real-field test cases for validating their numerical models, (b) to facilitate data access by indicating relevant bibliographic references, and (c) to identify test cases of potential interest worthy of further research.

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Karakteristik Gelombang Stoneley dalam Menentukan Permeabilitas Reservoir Sumur Pemboran

Jurnal Pendidikan Fisika dan Teknologi ◽

10.29303/jpft.v1i2.243 ◽

2017 ◽

Vol 1 (2) ◽

pp. 103

Author(s):

Kosim Kosim

Keyword(s):

Field Data ◽

Attenuation Factor ◽

Rock Permeability ◽

True Value ◽

Rock Formations ◽

Depth Position ◽

Permeable Rock ◽

Measurement Area

In-situ permeability is an important factor in determining whether an economical drilling oil wells to be mined. Therefore, the calculation in determining the true value of permeability with an attempt to take a further decision, whether the industry is continued or not. Research through study literature is obtained a mathematical modeling from Matheu and Toksoz's work which contains the components of acoustic wavesattenuation factor and rock permeability factor. Furthermore, by combining some of the concepts and theories, mathematical models are used for acoustic field data logs and other data which are required to get permeability. Data from the acoustic log is analyzed to determine the time delay for P, S and Stoneley waves, then determination of the speed, frequency and attenuation factor, especially for wave Stoneley. In this permeability calculations, it is assumed that the condition of the rock formations in the area of measurement is a permeable rock and contains fractures. The results show that the permeability in measurement area at a depth position indicates suitable with the data of rock state.

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Structural Performance of a Precast Concrete Modular Beam Using Bolted Connecting Plates

Applied Sciences ◽

10.3390/app112412110 ◽

2021 ◽

Vol 11 (24) ◽

pp. 12110

Author(s):

Kyong Min Ro ◽

Min Sook Kim ◽

Chang Geun Cho ◽

Young Hak Lee

Keyword(s):

Precast Concrete ◽

Steel Plates ◽

Structural Performance ◽

Modular System ◽

Beam Specimen ◽

Test Results ◽

Reinforcing Bars ◽

Bolted Connection ◽

Modular Units ◽

Modular Structures

In modular structures, prefabricated modular units are joined at the construction site. Modular structures must ensure splicing performance by connecting modular units sufficiently. The bolted connection using steel plates may suffer from alignment issues and corrosion problems. In a precast concrete (PC) modular system, there is difficulty grouting the sleeves when splicing reinforcing bars. This study proposed a PC modular beam using a bolted connecting plate to deal with issues in typical steel modules and PC modules. The structural performance was evaluated by flexural and shear tests on two monolithic beams and two proposed PC specimens. The test results showed that the structural performance of the PC modular specimen was 88% of that of the monolithic reinforced concrete (RC) beam specimen and 102% of the strength calculated by ACI 318-19. Therefore, the proposed PC modular system using bolted connecting plates can solve the problems observed in typical steel and PC modules and improve the structural performance.

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On the Clague–Mathews relation for jökulhlaups

Journal of Glaciology ◽

10.3189/172756503781830836 ◽

2003 ◽

Vol 49 (165) ◽

pp. 161-172 ◽

Cited By ~ 31

Author(s):

Felix NG ◽

Helgi Björnsson

Keyword(s):

Field Data ◽

Time Dependent ◽

Water Volume ◽

Volume Data ◽

Physical Origin ◽

Flood Hydrograph ◽

Data Record ◽

Flood Magnitude ◽

Discharge Volume ◽

Lake Systems

AbstractIn the empirical study of jökulhlaups, the peak discharge, Qmax, and water volume drained by the ice-dammed lake during the floods, Vt, appear to follow a power-law relation , where K are b are constants determined from field data. First identified by Clague and Mathews (1973), this relation is a useful reference for predicting flood magnitude, but its physical origin remains unclear. Here, we develop the theory that connects it to contemporary models for simulating the flood hydrograph. We explain how the function Qmax = f(Vt) arises from Nye’s (1976) theory of time-dependent water flow in a subglacial channel coupled to a lake, and we describe how discharge–volume data record the (monotonically increasing) form of this function so long as the lake is not emptied in the floods. The Grímsvötn jökulhlaups present an example where, because of partial draining of the lake, agreement between the model-derived f and data is excellent. It is documented that other lake systems drain completely, but we explain how the exponent b ≈ 2/3 observed for them collectively is due primarily to a scaling effect related to their size, modified by other factors such as the flood initiation process.

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