Advances in Civil Engineering

Research Article

Dynamic Analysis of Construction and Demolition Waste Management System (A Case Study of Tehran, Iran)

Table 1

Variables in the stock and flow diagram.
#TypeNameUnitsEquation
1StockPOPThousand personsNet population growth rate
2StockArea of houses builtMillion m2Rate of housing construction
3StockTotal C&D waste landfilledMillion m3Rate of landfilling
4StockTotal CO2 emissionTon CO2 eqRate of CO2 emission
5StockTotal energy consumptionTon oil equivalentRate of energy consumption
6FlowNet population growth rateThousand persons (year)Factor of net population growth ratePOP
7FlowRate of housing constructionMillion m2 (year)SMOOTHI (demand of new housing, 2.6, 13.646)
8FlowRate of landfillingMillion m3 (year)C&D waste generation rate
9ConstantLCA-energy-naturalKgoe (ton)2.3024
10FlowRate of energy consumptionTon oil equivalent (year)(1.6demand of aggregate“LCA-energy-natural”)1000
11ConstantLCA-CO2-naturalkg CO2 eq (ton)4.4609
12FlowRate of CO2 emissionTon CO2 eq (year)(1.6demand of aggregate“LCA-CO2-natural”)1000
13LookupFNPGR lookupThousand personsHistorical data
14AuxiliaryFactor of net population growth rate—FNPGR lookup (time)
15LookupEFA lookupm3/m2Historical data
16AuxiliaryEffect factor of aggregatesm3/m2EFA lookup (time)
17AuxiliaryFixed unit price of aggregatesUSD (m3)Unit price of natural aggregate + unit cost of landfilling
18AuxiliaryFixed unit price of housing constructionUSD (m2)Fixed unit price of aggregateseffect factor of aggregates
19AuxiliaryDemand for new housingMillion m2ABS ((0.005297fixed unit price of housing construction) + (0.156357POP) − (0.05343GDP) − 1083.34 − area of houses built)
20LookupNGDP lookupThousand USDHistorical data
21AuxiliaryNormal GDPThousand USDNGDP lookup (time)
22AuxiliaryGDPThousand USDNormal GDP + ((fixed unit price of housing construction/1000)rate of housing construction) − fixed price of aggregates
23LookupPA lookupm3/m2Historical data
24AuxiliaryAmount of aggregatesm3/m2PA lookup (time)
25AuxiliaryDemand of aggregateMillion m3Percentage of aggregatesrate of housing construction
26ConstantDensity factor—0.62
27AuxiliaryExtraction amountMillion m3Demand of aggregatedensity factor
28LookupURRQ lookupm3/m2Historical data
29AuxiliaryUrban reduction ratio of quarriesm3/m2URRQ lookup (time)
30AuxiliaryLand-use of quarriesMillion m2Extraction amounturban reduction ratio of quarries
31ConstantTotal constructable areaMillion m2240
32LookupURRL lookupm3/m2Historical data
33AuxiliaryUrban reduction ratio of landfillingm3/m2URRL lookup (time)
34AuxiliaryLand-use of landfillMillion m2Total C&D waste landfilledurban reduction ratio of landfilling
35LookupLUAR lookup—Historical data
36AuxiliaryLand-use/area ratio—LUAR lookup (time)
37AuxiliaryLand-use of houses builtMillion m2Area of houses built“land-use/area ratio”
38AuxiliaryRemained constructable areaMillion m2MAX (total constructable area − “land-use of quarries” − “land-use of houses built” − “land-use of landfill,” 0)
39LookupUPNA lookupUSD (m3)Historical data
40AuxiliaryUnit price of natural aggregateUSD (m3)UPNA lookup (time)
41AuxiliaryPrice of natural aggregateUSDUnit price of natural aggregateextraction amount
42LookupUCL lookupUSD (m3)Historical data
43AuxiliaryUnit cost of landfillingUSD (m3)UCL lookup (time)
44AuxiliaryLandfilling costUSDUnit cost of landfillingrate of landfilling
45AuxiliaryFixed price of aggregatesThousand USD(Landfilling cost + price of natural aggregate)/1000
46AuxiliaryFixed unit price of aggregatesUSD (m3)Unit price of natural aggregate + unit cost of landfilling
47LookupRCW lookupm3/m2Historical data
48AuxiliaryRatio of construction wastem3/m2RCW lookup (time)
49LookupRD lookup—Historical data
50AuxiliaryRatio of depreciation—RD lookup (time)
51AuxiliaryRenovation area of existing housesMillion m2Area of houses builtratio of depreciation
52LookupRDW lookupm3/m2Historical data--lookup
53AuxiliaryRatio of demolition wastem3/m2RDW lookup (time)
54AuxiliaryC&D waste generation rateMillion m3(Rate of housing constructionratio of construction waste) + (ratio of demolition wasterenovation area of existing houses)