Conceptual quantity modeling of single span highway bridges by regression, neural networks and case based reasoning methods

Download
2012
Aşıkgil, Mert
Conceptual estimation techniques play an important role in determining the approximate costs of construction projects especially during feasibility stages. Moreover, pre-design estimates are also crucial for the contractors. With the help of the conceptual predictions companies can determine approximate project costs and can gain several advantages before tendering phase. The main objective of this thesis is to focus on modeling of quantities instead of costs and to develop quantity take-off models for pre-design cost estimation of bridge projects. Majority of the existing studies focus on modeling of costs for conceptual cost estimation. This study includes modeling of the quantity take off items in a specific single span highway bridge using three different techniques namely, linear regression, neural network and case based reasoning. During this study 40 single span highway bridge projects whose owner is Republic of Turkey General Directorate of Railways, Ports and Airports Constructions were investigated and models for each work item were developed. Then by integrating the quantity take off estimations with unit costs, total project costs were calculated. As a result by evaluating the prediction performance of the models, comparison of the methods was achieved. Results are discussed along with the advantages of the proposed method for conceptual cost estimation of bridge projects.

Suggestions

Modelling of strengthened hollow brick infills
BARAN, MEHMET; Ozcelik, Ramazan; Sevil, Tugce; Canbay, Erdem (2013-02-01)
Strengthening the existing hollow brick infill walls by bonding high-strength precast concrete panels or applying steel fibre reinforced mortar was found to be an occupant-friendly seismic retrofitting technique for the buildings in use with deficient reinforced concrete structural systems. Both techniques convert the existing non-structural hollow brick infill walls into load-carrying structural members. To verify the effectiveness of the techniques, 20 reinforced concrete frames with hollow brick infill w...
Determination of a price index for escalation of building construction costs in Turkey
Kahraman, Serhan; Sönmez, Rifat; Department of Civil Engineering (2005)
Construction cost indices are developed to measure the degree of price variations in construction material and labor costs. However, each specific type of construction is a combination of unique set of materials and labor. As such, the degree of price variations referring to each specific type of construction shall be measured by specific price indices, in order to achieve more accurate results. In Turkey, Producer Price Index (PPI) published by State Statistics Institute is commonly used for the escalation...
Improving sub-contractor selection process in construction projects: Web-based sub-contractor evaluation system (WEBSES)
Arslan, Gokhan; Kivrak, Serkan; Birgönül, Mustafa Talat; Dikmen Toker, İrem (Elsevier BV, 2008-05-01)
One of the most important phases in the construction industry (CI) is the bidding process. During the bidding process, selecting the most appropriate sub-contractors (SCs) for the relevant sub-works is highly critical for the overall project performance. In order to select the most appropriate SCs for the project and prepare the most realistic and accurate bid proposal, general contractors (GCs) have to know all financial, technical and general information about these SCs. Within this context, GCs should co...
Experimental investigation of the seismic behaviour of panel buildings
Yüksel, S. Bahadır; Atımtay, Ergin; Department of Civil Engineering (2003)
Shear-wall dominant multi-story reinforced concrete structures, constructed by using a special tunnel form technique are commonly built in countries facing a substantial seismic risk, such as Chile, Japan, Italy and Turkey. In 1999, two severe urban earthquakes struck Kocaeli and Düzce provinces in Turkey with magnitudes (Mw) 7.4 and 7.1, respectively. These catastrophes caused substantial structural damage, casualties and loss of lives. In the aftermath of these destructive earthquakes, neither demolished ...
Modeling of Multi Open Phase Fault Condition of Multi-phase Permanent Magnet Synchronous Motors
Fei, Marco; Zanasi, Roberto (2011-09-10)
This paper deals with the modeling of multi-phase permanent magnet synchronous motors under multi open phase fault condition. The presented model is suitable for generic number of phases, generic shape of the rotor flux and generic number of open circuit faults. The motor model in fault condition can be used for faults occurring on both adjacent and not adjacent phases. The model can be very useful both for simulation and implementation of fault-tolerant control strategies.
Citation Formats
M. Aşıkgil, “Conceptual quantity modeling of single span highway bridges by regression, neural networks and case based reasoning methods,” M.S. - Master of Science, Middle East Technical University, 2012.