Effects of Design Quality on Delay in Residential Construction Projects

This study is conducted to establish the effect of design quality on project delay in building projects. It aims at: 1) investigating the major factors of design quality, 2) identifying the main delay factors in building projects, 2) establishing the relationship between design quality and delay in building projects. To achieve these objectives, a questionnaire survey is performed. Seventeen (17) factors that might affect design quality, and 15 delay factors are listed in a questionnaire form. Sixty (60) contractors and 40 consultants are asked to identify the severity of the identified factors. Results indicate that the top factors affecting design quality are: delay in payments by client for design services, staff allocation for many projects at the same time, copying and modifying from previous work to minimize time and cost, tight design schedule, lack of designer knowledge with techniques and materials available in the market. The study also concludes that the top five delay factors include: payments delay, poor labor productivity, lack of skilled manpower, frequent change orders and rework. Regression analysis for data collected from 36 building projects shows a good correlation between design quality and delay in projects. This study is the first one that addresses the problem of design quality in the West Bank in Palestine. Furthermore, it is the first study that addresses the effect of design quality on project delay in Palestine and the neighboring countries. It is hoped to be helpful for researchers and professionals to understand the impact of design quality on schedule delay.

Assessment on the Technical State of Spillway Concrete Gravity Dams in Lithuania

Spillway concrete gravity dams are exposed by loads and environment causing deterioration process. The article presents the concrete structure deteriorations, defects and technical state evaluation results of 34 Lithuanian spillway concrete gravity dams performed in 2006–2018. The typical deteriorations are: in piers’– crumbled protective layer of concrete, its corrosion, reinforcement corrosion, cracks in concrete, chipped edges; in spillway constructions’– concrete corrosion, bio–corrosion, concrete corrosion caused by cavitation; in outflow constructions – concrete corrosion, bigger cracks and deformations. According to results of technical state research, it was found that only 3% (1 SCGD) dams are in good technical state, 27% (9 SCGD) – moderate, 47% (16 SCGD) – satisfactory, 12% (4 SCGD) – unsatisfactory and 12% (4 SCGD) – in critical state.

Investigation of Social Opinion on Green Lifestyle and Eco-friendly Buildings. Decision Making Criteria

The present paper develops decision-making criteria through literature research to assess the social opinion on green life style and eco-friendly buildings. Validity of criteria was ensured among company executives and academic staff, based on elaborated criteria small pilot survey was performed and analysed. Current research focuses on the influence of demographic variables (e.g., age, gender) and individual subjective characteristic factors; external influencing factors (e.g., social norms, policies) are not used. According to the research results, our concept helps to outline the most crucial factors in industry regarding customer subjective requirements on eco-friendly building and innovative building materials. Nowadays companies need to meet customer requirements in order to adjust them in terms of eco-innovation approach and industry’s green ecosystem development and remove the gaps in value preposition. This paper helps to investigate respondents’ awareness, requirements, and willingness-to-pay for the eco-friendly houses.

Study of Four Passive Second Skin Façade Configurations as a Natural Ventilation System During Winter and Summer

The fight against climate change is a significant challenge, resulting mainly from the linear and extensive exploitation of natural resources, particularly fossil fuels. Its impacts are now recognized. The current climate models are neither sustainable nor ecological in economic and social terms, especially as we live in a century marked by galloping demography and urbanization. Researchers worldwide have paid great attention to passive solar design strategies such as double skin or Second Skin Façade. From this point, the present work aims to contribute to a better understanding of the feasibility of using a passive façade as a useful technology for natural ventilation to achieve potential energy savings and improve thermal comfort and indoor air quality. For this purpose, a parametric study was conducted for a room with four different southern facade configurations in six Moroccan climatic zones; the difference between each lies in the vent's position in the entrance and exit. This process was done by using COMSOL Multiphysics software. Velocity and volume flow rate fields were analyzed. The proposed configurations provided an average volume flow rate between 200 m3/h and 400 m3/h for a surface of 1 m2 of southern façade with an air vent area of 0.1mx0.2m.

Modular Timber Gridshells

Needs of considering environmental impacts and growing emphasise on using renewable resources is discussed also in the field of architecture and construction. Timber, as a key element, provides certain benefits with less negative environmental impact than non-renewable resources, represented by commonly used materials (e.g. concrete). Nevertheless, using the timber as a core element for constructing of multi-storey or large hall buildings can be more difficult due to limits of the wood. New task for architects and engineers therefore arises and the target is to come up with a feasible solution for using the timber as a core material, despite its features. One of the key requirements for wide use of load bearing timber structure systems is “modularity”. Many different forms of structures can be achieved by repeating the basic module to fulfil architect’s intentions. This article focuses on a large-span structure, based on gridshell type systems. Such modules could be simply prefabricated and connected to another module. Modules can be pretty small, which contributes to easy and cost-effective transportation. Nevertheless, technical requirement and limitation of such modules needs to be taken into consideration. Problems come up with using the same universal element in parts of structure with different character of load and stress. Also, universal element should fulfil various space and form requirements set by architect. Suggested construction system is based on “fractality”. The goal of the system is to fulfil requirement of final structure and space requirements by replacing the standard module by a predetermined number of sub-modules. Structure is then denser in exposed areas and sparser in others. Design module is than expected to be tested and put into practice for wide usage in construction projects where wood is desired as the core material.

Bypass in Urban Space: Creative Scenarios

Considering functional and experiential congestion in Kadıköy, the paper deals with the concept of “Bypass in Urban Space” in the context of the user-centred design. The case study is limited with the axis extending from Söğütlüçeşme and General Asım Gündüz Street which is connected to the main artery. Kadıköy, as one of the rapidly growing and transforming urban centres in Istanbul, reflects variable traumas in terms of human-environment behaviour relationships. A research model is developed to identify these traumas and produce a solution through bypassing the congestion in the area. Within the scope of the study, it is aimed to contribute to the dynamic structure of the city by creating new functional experience spaces in the capillary streets. On the other hand, it is aimed to design the spaces that lead the user to stop and perceive the environment beyond its transition function of the main artery within the dense pedestrian and vehicle traffic. By the research model, it is suggested multi-functional creative scenarios through the problems and hypotheses identified within the framework of the user-environment connection. Environmental and behavioural research, conceptual readings, sketch of ideas and visualization of conceptual studies, the designer scenarios are the main phases of the research as well as developing a proposal within the scope of contribution to the field. Most of design solutions analyses several dynamics such as bypass, main artery, in-between space, spatial conjunction, integration in urban space. So, it is aimed to design integrative mobile spaces for continuity of user-environment relationship beyond establishing a physical and visual connection.

Possibilities of Using Building Information Model Data in Reinforcement Processing Plant

While the AEC industry is moving towards digitalization off-site rebar prefabrication became a common practice. Now most companies use a long-established standard order processing method, where the customer submits 2D paper or PDF-based drawings. Subsequently, the manufacturers are obligated to make additional detailing, redrawing, calculations, and preparation of other required information for manufacturing. Thus, in this typical scenario, there is a great repetition of the same tasks, with the obvious loss of time and increased likelihood of human error. However, improvements can be made by the application of advanced digital production workflow and the use of open BIM standards (e.g., IFC, XML, BVBS). Therefore, this paper presents the typical data flow algorithm in contrast to the automated data flow for reinforcement manufacturing. Further, the two approaches are compared and analyzed based on Multi-Criteria Decision Making (MCDM) methods. The results have shown promising prospects for companies willing to automate their data flow processes by the use of 3D drawings and digital data from the BIM model in their plants.

Political Economy of Straw Houses: Traditional and Contemporary Way of Enhancing Sustainability of the Buildings

Cities, as production and consumption hubs, cause significant amount of global CO2 emissions and energy consumption. Climate change challenges world’s welfare due to the global warming. Cities’ environmental footprint can be reduced with the help of energy efficient and sustainable built environment which can further contribute to the wellbeing and welfare of the urban population contributing to the solution of the fuel poverty. Straw is a traditional and contemporary material having outstanding technical characteristics (e.g. thermal insulation). Straw is a traditional material as it has been used in sheltering starting from the ancient times. Straw is a contemporary material as it is used even in small buildings with the help of innovations. Furthermore, it is a cost effective material from initial investment as well as maintenance and repair aspects. Straw houses can reduce energy consumption. This can reduce countries’ trade deficit due to the reduced demand for energy import, contributing to the solution of the fuel poverty. Straw is environmental friendly natural material. Constructing straw houses is important for sustainable living. Giving importance to the straw house construction can help reduction in the CO2 emission and in the energy consumption. Based on an in-depth literature review, this paper investigates political economy of straw houses and straw houses’ contribution to the sustainability performance of the built environment. This paper introduces to the literature political economy of the straw houses and provides recommendations on how to widespread the use of straw houses.

Impact of Displacement Phenomena on Landscape Identity: Application of Cultural Values Model

The research attempted to discover the impact of displacement phenomena on the identity of landscape, by using Janet Stephenson’s Cultural Values Model to study and analyze cultural landscapes. The model was chosen due to its universality, simplicity and embodiment of the relational concept of landscape perception and evaluation. The result of landscape evaluation depends on the characteristics of both landscape and observer, as well as on the relation of the object and subject. In order to understand the complexity and diversity of landscape and its identity, these were analyzed through a ternary system, consisting of forms, practices, and relationships, i.e. what is seen, what is happening and what it means to those who see and use it. The research represents a feasible and pragmatic approach to understand the complexity of landscape and its identity, by tracing back their retrospective changes due to the impact of displacement phenomena – a shift of objects, behaviours or relationships. Through this theoretical and methodological model, multiple universal correlational patterns were developing, in which the three components encountering the displacement behave and interact with each other, leading to an ambiguous impact on landscape identity and the socio-cultural quality of the human living environment. By studying and time-tracking different landscape cases that experienced major displacements from around the world to one of landscape’s systemic components, the research results show some regular patterns in landscape identity changes, and how its structural tangible and intangible system performs and effects in creating, or destroying landscape identity, defying the limits of spatial and historical context.

An Analysis of the Plan and Facade Typologies of Boyabat’s Traditional Turkish Houses

This study examines the traditional housing culture of a town in northern Turkey. We aimed to determine the characteristics of traditional Boyabat houses. The Çay District, which was chosen as a case study, is the core of the housing pattern of Boyabat. This study analyzed the features, plan and facade types of these houses in order to produce a table of their plan and facade typology. Documenting the vernacular architecture of Boyabat will assist the conservation of the settlement’s traditional texture. This data can also serve as a guide for the local municipality’s site management projects and be passed on to future generations.