CHEMICAL ENGINEERING TRANSACTIONS
VOL. 67, 2018
A publication of
The Italian Association
of Chemical Engineering
Online at www.aidic.it/cet
Guest Editors: Valerio Cozzani, Bruno Fabiano, Davide Manca
Copyright © 2018, AIDIC Servizi S.r.l.
I SBN 978-88-95608-64-8; I SSN 2283-9216
Exponential Predictive Model of Excavation Damages on a
Natural Gas Distribution Network Situated on Metropolitan
Regions of São Paulo State – Brazil
Flávio Vasconcelos da Silva
a
, Rodrigo Battaglini Pirani
b
, Sérgio Rodrigues*
b
,
Stefano Fernandes De Sa
b
a
MSc, School of Chemical Engineering, State University of Campinas, Brazil
b
Comgás, 134 Capitão Faustino de Lima Street, 03040-030, Brás, SP, Brazil
rodrigues.sergio1965@gmail.com
This study develops and demonstrates an exponential equation whose variables, Brazilian industrial quarterly
GDP index and the total natural gas pipe length (transmission, distribution and external services) of a Brazilian
distribution company, has the ability to predict the Absolut amount of third party excavation damages (annual
monthly average value). With the use of the quarterly macroeconomic projection of Brazilian industry GDP and
the company expansion scenarios is possible to simulate the amount excavation’s damages and establish an
adequate dimensioning of actions for the predicted scenario over the natural gas pipes inside metropolitan
areas.
1. Introduction
The natural gas is pipe and delivered through an underground network for houses, residential, commerce
buildings, industries and gas stations. Others companies of infrastructure uses underground pipes to deliver
services as electricity, water, steam, communications, sewage, etc. Boosted by private and public resources
that affect the GDP they performing excavations to maintain and expand these network systems. Maintenance
actions are recognized as a risk factor (Okoh and Haugen, 2013), excavation damages are recognized
together with internal and external corrosion as one of the most frequently causes of cost consequences in
natural gas transmission and as the first in distribution pipeline infrastructures (Simonoff et al, 2009). The
effects on structural building components due to gas pipelines incidents involving high-pressure transmission
in urban areas received recently studies to model and predict their impact (Russo et al, 2014). There are well-
identified causes and consequences but for occurrence predictions, only an exploratory study over excavation
damages on pipes that identified the existence of cyclical forces that govern damage function (Rodrigues,
2012).
The focus of this study was to verify a correlation between the GDP resources level with the third party
damage normalized by the network length (km) and develop a quantitative prediction model not in a time
domain but a result of time independent variables.
2. Concession rules and the studied area
The Comgás, CG, was founded in 1872, and is a Brazil's distributor of piped natural gas with over 1 million of
customers in residential, commercial and industrial segments over 80 municipalities in the São Paulo and
Campinas metropolitan regions, and the regions of Santos and Paraiba Valley, 27% of Brazil's GDP comes
from the CG concession area. As the distributing piped gas is a public service, it is subject to standards and
requirements stated in the agreement signed with the concession authority, the Regulatory Agency of
Sanitation and Energy of the State of São Paulo, ARSESP. (Comgás, 2018).
DOI: 10.3303/CET1867134
Please cite this article as: Vasconcelos Da Silva F., Battaglini Pirani R., Rodrigues S., Fernandes De Sa S., 2018, Exponential predictive model
of excavation damages on a natural gas distribution network situated on metropolitan regions of são paulo state – brazil, Chemical
Engineering Transactions, 67, 799-804 DOI: 10.3303/CET1867134
799