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An Overhead Costs Assessment for Construction Projects at Gaza Strip
Nabil I. El-Sawalhi,
Ahmed El-Riyati
Issue:
Volume 3, Issue 4, July 2015
Pages:
95-101
Received:
15 May 2015
Accepted:
28 May 2015
Published:
11 June 2015
Abstract: An overhead cost of projects has significant role and influence on the performance of the construction companies. In addition, maintaining a good performance and quality of work away from possible loss. The purpose of the research is to examine the overhead costs management practice in the construction industry in the Gaza Strip. The awareness of construction companies and techniques followed by the contractors in estimating the overhead costs, affecting factors and mitigation measures was examined. A structured questionnaire supported by personal interviews was used to collect information. Sixty-three contracting companies working in the construction industry in the Gaza Strip were surveyed. The analysis shows a good awareness of the concept of overheads costs and its components. Gaza Strip Contractors follow precise practices to estimate the overheads costs. Contractors are taking several precautionary measures to minimize any risks associated with overheads costs. Factors affecting the estimation of overhead costs are including the management capacity of the company and its policy, led by the company's experience and ability to implement the project within the time frame. There are other factors related to the working environment of the project, especially the closure of commercial crossings of the Gaza.
Abstract: An overhead cost of projects has significant role and influence on the performance of the construction companies. In addition, maintaining a good performance and quality of work away from possible loss. The purpose of the research is to examine the overhead costs management practice in the construction industry in the Gaza Strip. The awareness of c...
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Exploring Practical Optimal Topology for Reinforced Concrete Moment Resisting Frame Structures
Issue:
Volume 3, Issue 4, July 2015
Pages:
102-106
Received:
1 June 2015
Accepted:
15 June 2015
Published:
2 July 2015
Abstract: Topology optimization of reinforced concrete frames is one of a challenging issue in structural engineering. Frame structures, unlike trusses, must provide useable spaces. Architectural requirements affect greatly the layout of the structure and optimal spans, which are obtained theoretically. Sometimes optimal topologies are not possible for real projects because the calculated optimal spans do not provide architectural requirements. In this article, however, exploring for optimal spans for reinforced concrete frames is investigated considering the architectural limitations. For this purpose, three groups of spans, including 5.6m, 7.5m and 11.2m, are considered based on the parking limitations and then optimal practical sizing for the structures are obtained numerically for 5-storey and 10-storey structures. All models are estimated and considerable differences are shown by diagrams. The optimal topology is proposed for 5-storey to 10-storey buildings with different useable spans.
Abstract: Topology optimization of reinforced concrete frames is one of a challenging issue in structural engineering. Frame structures, unlike trusses, must provide useable spaces. Architectural requirements affect greatly the layout of the structure and optimal spans, which are obtained theoretically. Sometimes optimal topologies are not possible for real ...
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Analysis of Flanged Rectangular Waveguide Probe for Nondestructive Absorbing Materials Characterization Using FDTD Simulation
Issue:
Volume 3, Issue 4, July 2015
Pages:
107-115
Received:
2 November 2014
Accepted:
11 December 2014
Published:
2 July 2015
Abstract: In this paper, the flanged open-ended rectangular waveguide probe technique is studied using Finite Difference Time-Domain simulation (FDTD). Both generally lossy and high loss electromagnetic materials are considered to investigate the influence of probe flange size, operating frequency and sample thickness on complex permittivity (εr) and permeability (μr) and thickness measurement. Variations in the probe flange size for different frequencies, material under test type and thickness are simulated. It is found that using of waveguide probe with finite flange affects probe input reflection coefficient substantially in some cases. To verify the obtained simulations results, a series of experiments are conducted for this purpose. Both εr and μr of material under test under different measurement conditions are extracted using FDTD modeling and compared with reference data. In order to evaluate the degree of accuracy of this technique, error analysis to various sources of errors and most importantly the effect of finite flange size are also demonstrated by using the measured data compared with the analytical model results. Simulations and measurements results have shown that the consideration of probe flange large enough for the practical purpose to be infinite is restricted by the constitutive parameters (εr and μr) and operating frequency as well as the thickness of the material under test. The FDTD simulations and experiments results are presented.
Abstract: In this paper, the flanged open-ended rectangular waveguide probe technique is studied using Finite Difference Time-Domain simulation (FDTD). Both generally lossy and high loss electromagnetic materials are considered to investigate the influence of probe flange size, operating frequency and sample thickness on complex permittivity (εr) and permeab...
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Case Report
Analysis of Seepage Under Hydraulic Structures Using Slide Program
Hala Kathem Taeh Alnealy,
Najm Obaid Salim Alghazali
Issue:
Volume 3, Issue 4, July 2015
Pages:
116-124
Received:
19 June 2015
Accepted:
27 June 2015
Published:
7 July 2015
Abstract: In this study, “SLIDE” program was used to analyze seepage flow under the hydraulic structure through single and multi- layers soils and its effect on structures with inclined cut-off at downstream, at upstream, and at both of them. The distribution curves of uplift pressure along the floor had been reached as well as the distribution of exit gradient at downstream. In the first experiment which included hydraulic structure based at single layers, results are compared with the general case (no cut-off) obtained when using single cutoff, minimum value of the uplift pressure and seepage quantity occurred when using cutoff at upstream side with Ө=45° which given decreasing 40.3%, 28.5% respectively and minimum value of exist gradient occur when using cutoff at downstream side with Ө 120° which given decreasing 8.03%. while using double cutoff minimum value of uplift pressure ,exist gradient ,seepage occur when using double inclined cutoff at upstream with Ө = 45° and downstream side with Ө 120° which given decreasing (42.1%, 8.03%, 30%) its contacted that using double cutoff given decreasing in each uplift pressure, exist gradient, seepage at the same time.
Abstract: In this study, “SLIDE” program was used to analyze seepage flow under the hydraulic structure through single and multi- layers soils and its effect on structures with inclined cut-off at downstream, at upstream, and at both of them. The distribution curves of uplift pressure along the floor had been reached as well as the distribution of exit gradi...
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Construction of Bridge Decks with Pre-Cast, Pre-Stressed Concrete Deck Planks
Issue:
Volume 3, Issue 4, July 2015
Pages:
125-128
Received:
28 June 2015
Accepted:
4 July 2015
Published:
10 July 2015
Abstract: The research analyzes the use of precast prestressed concrete deck planks in the construction of bridge decks. Will the use of these precast prestressed styles PPC’s aid in the durability of the construction, or will there be issues in the initial stages itself that has to be handled? And whether these constructions are in any way cost effective (as in lower number of rejection rates of the planks manufactured) are some the questions that are investigated here. A case study based research method has been adopted here. The case study is that of the bridge deck replacements that were carried out by the Illinois Department of transportation in 1999-2000. The bridge deck replacements were done by means of PPCs. The research also aims to find whether the bridge deck replacements that were carried out had early performance issues. It was established that there were indeed early performance issues, but these could be mitigated by means of load testing and the use of high-grade materials.
Abstract: The research analyzes the use of precast prestressed concrete deck planks in the construction of bridge decks. Will the use of these precast prestressed styles PPC’s aid in the durability of the construction, or will there be issues in the initial stages itself that has to be handled? And whether these constructions are in any way cost effective (a...
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