Infill Projects Research Articles

Clustering tall building typologies and analyzing their composite impacts on wind environments in infill development projects

Clustering tall building typologies and analyzing their composite impacts on wind environments in infill development projects

Key Success Factors of Urban Infill Development: A Conceptual Framework

Current cities, especially megacities, are going through a continuous increase in population size because the city extends beyond its urban borders, causing what is called urban sprawl, which constitutes the real problem for cities at present. Also, these megacities have many informal areas and urban dilapidated areas because of the ancient period since their establishment, from which the city has suffered greatly. Hence, the need to determine development methods that should be within the city instead of expanding outside its borders, and many methods have been reached that can be used to solve this problem, the most important of which is infill development. The research methodology focused on reviewing the literature of the study and discussing the best international practices to arrive at a first draft of a list of key success factors for infill development projects and reviewing it with a group of experts who developed it until the final approved version was reached. The result of these procedures was to arrive at a conceptual framework for the key success factors for infill development. This conceptual framework applies to any city to ensure that infill development projects are successful with the highest possible quality and reflect positively on the city and its residents.

Expanding Affordable Middle Housing Options in Single-Family Neighborhoods

Problem, research strategy, and findings By examining the Residential Infill Project (RIP) in Portland (OR), this study addressed the ongoing debate on single-family zoning reform, focusing on the effectiveness of legalizing middle housing in expanding housing options in single-family neighborhoods. The analysis revealed a substantial increase in the proportion of middle housing in residential developments in single-family zones, from 13.4% before the RIP implementation to 44.7% in the 2 years after RIP’s adoption. Almost 40% of these post-RIP middle housing permit units were replacements for existing homes. Compared with single-family housing developments, middle housing projects were more likely to be in neighborhoods with greater density, better walkability, and lower income. The RIP broadened middle housing accessibility by allowing their development on non-corner lots, at greater distances to the city center, and in medium-density single-family zones. The RIP’s approach to regulating development density and building size significantly reduced the average size of middle housing units in single-family zones to less than half that of single-family homes. Given the strong correlation between home sizes and prices, it seems reasonable to infer that middle housing units have become considerably more affordable since the enactment of the RIP. Takeaway for practice Eliminating single-family zoning represents an initial step in expanding housing options in single-family neighborhoods. More comprehensive zoning reforms are essential for meaningful improvements in housing affordability and diversity. Cities must reassess and amend zoning codes, particularly development standards, to foster innovation in middle housing development and encourage developers to build smaller homes to lower housing costs.

Regulatory islands: a case study in tactical community zoning

Despite the clear environmental and economic benefits of denser forms of housing, the ability to construct such housing remains elusive. Restrictive zoning policies and local coalitions of Not in My Backyard activists make the construction of dense housing within established neighbourhoods a near impossibility in jurisdictions throughout the United States. The purpose of this article is to illustrate how architects might leverage community coalition building and the critical interpretation or ‘hacking’ of local zoning ordinances to realise dense, infill housing projects even within otherwise highly conservative policy environments. Using Pier Vittorio Aureli’s history of settlement form and property rights as an initial contextual framework, the article outlines how infill housing might adopt an alternate view of housing development, subverting the primacy typically assigned to individual private property rights and financial speculation. Sited on an infill lot within one of Lincoln, Nebraska’s older neighbourhoods, the project relies on a non-normative, strategic implementation of a Community Unit Plan zoning mechanism to enlist neighbourhood support and establish higher levels of allowable density. This, in combination with the implementation of a Community Land Trust, allows the project to introduce a greater quantity and diversity of housing types that offer possibilities for home ownership, affordable rental opportunities and even temporary or supportive housing in areas historically dedicated solely to single-family housing models. Ultimately, the significance of the project rests not in its formal novelty but in its demonstration of an immediate and attainable means through which denser forms of housing might be realised.

A new one-dimensional consolidation creep model for clays

Creep deformation is a prevalent form of deformation infill projects, and accurately characterizing the creep of fill soils is essential for ensuring the safe and reliable operation of these projects. To develop a novel variable-order fractional creep model that describes the consolidation creep behavior of fill soils, this research enhances the fractional order algorithm to achieve more precise fractional orders and determine the variable order function. Consequently, a novel variable-order fractional element featuring viscoelastic memory effects is introduced and formulated as a model. Unlike the traditional Maxwell model, the new model is simpler, has fewer parameters, and includes a memory effect that reveals the characteristics of mechanical properties over time during the creep process. In addition, this study validates the proposed model's applicability and modeling benefits through one-dimensional consolidation creep tests on red clay at the fill site. The findings indicated that the change in fractional order in the new model should be an exponential function. The trend of decreasing fractional order with time is consistent with the soil consolidation creep-hardening behavior, suggesting that the variable fractional order function represents the changing nature of the soil. In this study, exploring fractional order laws reveals the physical significance of the fractional order element and enables the composed model to make effective predictions of relevant working conditions.

Coding for predictive built environments: building and street typology choices in form-based codes

ABSTRACT Form-based codes (FBCs) pursue alternative built environments that integrate design-focused approaches for the purpose of fostering predictable development outcomes. The emphasis of FBCs on legitimate building types and physical parameters may provide local authorities with new opportunities to incent a variety of sustainable design features. Despite the code’s recent popularity in urban infill and suburban retrofit projects, little research exists to explain the expected benefits of form-based approaches. This study evaluates the evolution of FBCs across diverse cities by relating a range of geographical scales to differing contextual conditions. Focusing on five FBCs adopted in the United States between 2010 and 2015, building and street design elements are analyzed to investigate the linkages between development context and built outcomes. This study supplements prior research on design coding by demonstrating that the local and metropolitan contexts of FBCs can help explain how placemaking goals may be achieved. The typology framework presented in this paper also serves as a minimum set of standards for reconciling the public’s expectation for amenities with the private sector’s willingness to contribute their resources to the local built environment.

Developer Response to the Removal of Minimum Parking Requirements in Buffalo

The widespread adoption of minimum parking requirements in American zoning codes has resulted in off-street parking provision as a compulsory part of the land development process. A robust academic literature on the effects of minimum parking requirements has identified that parking prioritization induces more driving and results in harmful consequences such as traffic congestion, air pollution, and sprawl. On the adoption of its 2017 Unified Development Ordinance (Green Code), Buffalo (NY) became the first major city in the United States to implement the complete removal of minimum parking requirements. The new zoning code sans parking minimums offers real estate developers greater flexibility on new real estate development projects because off-street parking lots can be reduced in size or removed altogether from developments, and land previously reserved for required off-street parking can now be used in other ways on development sites. To better understand the development responses to parking deregulation in Buffalo, we conducted a series of in-depth interviews with 10 real estate development and lending professionals that have been involved in new development projects since 2017. Three takeaway messages emerged. First, when minimum parking requirements are removed, parcels amid high-walkability and multimodal travel opportunities are more desirable for development. Second, lower parking ratios are useful for infill development projects and contribute to filling existing gaps in the urban fabric. Third, the removal of parking requirements enables developers to benefit from increased feasibility on projects, both in relation to financial viability and the ability to configure developments on smaller urban parcels.

Urban Consolidation in Australia's Four Largest Capital Cities: Tangible Outcomes of Inner-city Apartment Developments and Their Implications for Urban Planners

Urban consolidation has become dominant practice in metropolitan planning across Australia’s four largest capital cities – Sydney, Melbourne, Brisbane and Perth – as a result of the escalating need to manage rapid population growth and limit urban expansion. The strategic push for higher-density residential dwellings, such as apartment complexes, around strategic infill locations and activity centres is partly in response to the rising demand for more diversity in Australia’s housing stock. Supplementary factors include demographic shifts, cultural changes, and ongoing concerns regarding housing affordability, liveability, accessibility and climate change. Although this style of development has been at the forefront of state government planning agendas for at least a decade, presently little is understood about the outcomes of inner-city apartment buildings, particularly in Perth, as most of the research on modern infill projects in Australia focuses on Sydney and Melbourne.The primary aim of this research is, therefore, to investigate the outcomes of high- Density inner-city apartment developments for residents, the community and urban planners within Australia’s four largest capital cities, with a particular focus on Perth. The research is informed by a review of academic and government literature concerning infill and apartment developments in the specified cities, as well as a case study of a recently constructed apartment building in one of Perth’s main activity centres, Fremantle. The study found that state and local governments are not always achieving ‘good density’, nor are they developing apartment buildings that engender positive outcomes for both residents and the community. Some of the challenges that must be overcome if this is to change include designing apartments that cater to the needs of a diverse population, getting state governments to provide more support for local councils, and engaging earlier and more effectively with local communities. The research findings provide council planners with a better understanding of the challenges faced by residents in new apartment buildings, as well as the difficulties of meeting community expectations and planning ‘good density’, so that future planning policies and urban development can be more suitably informed.

Alternative Approaches to Urban Regeneration and Infill Planning

In Finland, cities consider infill development as a means for urban regeneration in existing suburbs. However, the preconditions for development may vary: some areas are more attractive for infill development projects than others. Therefore, cities must align their urban regeneration approaches with the specifics of the context.
 This paper builds on the notions that the prevailing growth-dependent urban planning paradigm is not functional in areas demarcated by low growth or stagnation. Planning that seeks to bring value for the localities by appreciating their strengths and non-monetary assets might provide grounds for alternative planning approaches. From these starting points, we explore how Finnish urban planners align their urban regeneration approaches with different contexts. We aim at identifying when the growth-dependent approach is used, whether alternative approaches are deployed, and what are their underlying logics. Our analytical framework originates from organizational learning theory of action inquiry. It explains how urban regeneration visions, strategies and actions are adjusted to low growth contexts. The empirical material consists of three urban regeneration cases in the Finnish City of Turku.
 As a result, three approaches to urban regeneration with different emphases on infill development are depicted and discussed. The growth-dependent approach is used in areas with strategic importance for the City, and possibilities for urban growth. Alternative approaches seek to support local development initiatives or inspire development in areas where it does not yet exist. The contribution of this exploratory paper is to demonstrate that urban planners in Finland deploy alternatives to growth-dependent planning and provide conceptualizations of alternative planning approaches.

Improving local pedestrian-level wind environment based on probabilistic assessment using Gaussian process regression

Many wind comfort assessment standards have been proposed to evaluate wind comfort and safety in spaces with intended use for pedestrians, such as pathways, building entrance areas, amenity spaces, and outdoor sitting spaces. However, the optimization of the wind environment presents a unique combination of complexities in assessment, simulation, and design. Conventionally, designers rely heavily on wind tunnel experiments or computational fluid dynamics simulations based on which only limited proposals are examined to select the one with the best wind performances. A new design framework for proactively improving the wind conditions at various measuring positions is demonstrated in this paper. Gaussian process regression models are combined with the Latin hypercube sampling method to approximate the relationships between design variables and wind velocities at discrete locations. Gaussian process regression is a non-parametric model well-suited for modeling the non-linear and stochastic wind behaviors. Moreover, it can provide the prediction mean and variance, and the latter is incorporated into a prediction quality function to quantify the modeling uncertainty. In the case study, with the objectives of maximizing the winter and summer wind comfort and minimizing the modeling errors, the robust and near-optimal designs of a target building in an infill development project are explored using the evolutionary search algorithm. We believe that this framework can be migrated to other urban design practice to better predict and simultaneously optimize the microclimate performances at locations of interest, such as solar access, indoor ventilation efficiency, and thermal comfort.

Is neighborhood satisfaction related to density perception? Promoting liveable and sustainable land use planning

While sustainable land use planning ensures land preservation through urban compactness, liveable residential environments are commonly associated with low density levels. Analyzing the relationships between density and neighborhood satisfaction (as a measure for liveability) may therefore help urban planners to offer sustainable infill projects that also guarantee liveability for the residents. Objective or subjective measures of density can be proposed. While the literature considering objective density is plentiful, the empirical work analyzing the relationships between density perception and neighborhood satisfaction is surprisingly scarce. In this study, we use a 2015 online survey in the Loire-Atlantique Département in France that provided 1,134 questionnaires, which we analyzed using a discrete choice experiment. We find that neighborhood satisfaction has no relationship to the perceived density of the built environment by individuals. What matters is peacefulness as another type of neighborhood perception. Healthcare accessibility is also valued by the residents.

Fracture Hits Mitigated Successfully in High-Pressure Stimulation Offshore Black Sea

This article, written by JPT Technology Editor Judy Feder, contains highlights of paper SPE 201422, “Successful Mitigation of Fracture Hits in High-Pressure Stimulation Using Bottomhole Gauges and an Optimized Engineering Design, Offshore Black Sea,” by Gabrijel Grubac, SPE, Radu Patrascu, and Peter Janiczek, SPE, OMV, et al., prepared for the 2020 SPE Annual Technical Conference and Exhibition, originally scheduled to be held in Denver, Colorado, 5–7 October. The paper has not been peer reviewed. This paper presents a case study of fracture interaction mitigation in a multistage horizontal stimulation of an offshore Black Sea well. The authors discuss a multifaceted approach in applying lessons learned and pre-job geomechanical analysis of depletion-induced stress differential and its effects on fracture interactions. Intrastage fracture interference presents unique challenges that typically are managed on a case-by-case basis. This study aims to present critical analyses that are paramount to planning stimulation treatments in highly depleted segments and reservoirs with close-proximity wells. Project Background The operating company began a field redevelopment project in 2013 for a field in the Black Sea that was already producing from horizontal wells with multi-staged fractured wells. The project comprises three treatment wells (A, B, and C) and seven offset wells (1 through 7). Because of time-critical operations and related costs, the original treatment wells and sidetracks (5,000-m-long measured depth horizontals) were completed with multistage stimulation sleeves and were operated by a ball-drop system from the surface. Infill drilling was implemented with the newly added sidetracks because of the maturity of the field and the desire to optimize the hydrocarbon drainage process. Well C was the first infill well. A multi stage fracturing campaign for Well C began in 2015. The complete paper presents a detailed discussion of issues—including strong fracture communication—identified, and mitigation steps attempted, during the infill project. Various simulation methods and depletion models that were tried and later rejected are also discussed. Several investigations were begun into how to predict, and subsequently avoid, fracture-driven interactions. Industry practice with huge quantities of water injection in the offset wells was not feasible because of the already-low economics of the treatment wells. A half-iterative process between reservoir modeling and fracture modeling was begun, and an actual reservoir pressure-depletion map was created on a sector basis. Similarly, the fractures were simulated using a grid-oriented fracture simulator in full 3D. Using this approach, it was also possible to match previously identified communication between wells and highly nonsymmetric fracture growth. The initial plan for the recent multi-stage fracturing campaign was to drill all wells closer in time to reduce localized depletion and to allow initial fractures from offset wells to act as a stress barrier to mitigate fracture growth in the direction of those wells. A matched reservoir and geomechanical model was used for the fracture simulation, and the actual depletion map for different time regimes was introduced. It was decided to redesign the fracture treatments and to shut in the offset wells 36 hours before the treatment, and to keep them shut in during the entire stimulation operation. At that point, it became clear that reservoir pressure depletion was one of the main causes of communication and also impeded optimal fracture geometries and hydrocarbon recovery.

A robust metamodel-based optimization design method for improving pedestrian wind comfort in an infill development project

Constructing a new building inevitably modifies the microclimate in its vicinity. We propose a metamodel-based optimization method to devise near optimal designs that minimize building’s adverse impacts on nearby pedestrians’ wind comfort in hot and cold seasons. Four design parameters, i.e., building width, building depth, building height, and building orientation, are considered for a greatly simplified building design task. Specifically, computational fluid dynamics (CFD) analyses are performed to calculate the mean wind velocity, while all CFD experiment samples are determined through the Box-Behnken design of experiment method. Based on 54 CFD experiments, the relationships between building design variables and the summer and winter mean wind velocities within a specified assessment area are learned using the response surface methodology. Finally, a genetic algorithm with the desirability function as the objective function is applied to identify near optimal design options under the robustness control (i.e., family error rate λ) for response surface models. The framework is applied to an infill development project to highlight its suitability in a real application. The experiment results show that as λ gradually decreases from 1 to 0.05, the overall desirability index dwindles from 0.33 to 0.22, consequently generating a more conservative optimal design decision.

Urban Infill as a Tool to Activate the Quality of Life in Traditional Cities

The research is based on the question of how can traditional cities cope with the demands of contemporary life? As the high efficiency of urban life in traditional cities or the so-called quality of life is the intended purpose of this paper. This goal can only be achieved by activating the health, social, economic and urban aspects of the place through prudent urban interventions in these environments. The research hypothesis confirms that urban infill projects, including deletions and additions, can improve the quality of life in these cities. Thus, the research problem summarizes the lack of studies dealing with improving the quality of life in traditional environments, which suffer from forced removal projects of some or all of the old tissue, and the difficulty of communicating with the requirements of contemporary life. The research was based on studying the phenomenon and making questionnaires for the study area of the old city of Najaf. Then, obtain conclusions that confirmed the research hypothesis and based on indicators that can be adopted to activate the quality of life in traditional cities.

Enhancing Sustainability of Historic Contexts Through Infill Landscape Projects Infill development as a catalyst for Rehabilitation

Development in historic areas is a very sensitive issue because of the importance of these areas and their multiple values of historical, cultural and economic. Development should aim to emphasize and maximize the value of this context and to make possible contributions to address weaknesses. The aim of this research is to investigate the extent to which the role of added development can be maximized in heritage contexts for sustainability. The study hypothesis is discussing the possibility of enhancing the sustainability of historic contexts through an integral infill landscape project based on the potentials of these projects. A questionnaire was conducted with architects and planners to determine the expected role of this type of development and how much contribution it should role. Case studies were selected to assess the extent to which the infill development in heritage domains could achieve sustainability. An analytical comparative study was done based on qualitative methods by studying the case studies of infill landscape projects that were added and positively affected the historic context. The research then proceeds with a set of conclusions and recommendations that can be applied when adding development in historic contexts.

Urban regeneration of "SoorMagra AL Oyoon" district

Egypt is considered one of the most historically rich countries around the world, not only for its famous ancient Egyptian monuments but also for its rich Coptic and Islamic heritage sites. Among which is the medieval Mamluk aqueduct of Sultan AL-Nasser Mohammadknown as " SoorMagra AL". However, despite its ionic location and great historic value, SoorMagra ALdistrict has been severely neglected and affected by the great population growth and urban sprawl leaving it urbanely deteriorated, poorly designed, and aching with slums, pollution, and destructive land uses.The research aims to propose a revitalization and urban development strategy forALdistrict through a number of urban interventions including the removal of slums and inappropriate land uses, reallocating suitable land uses, redesigning streets, pedestrian and bike lanes, green areas, and public spaces that respect the context and urban fabric of such a valuable heritage site.The proposed project is mainly a commercial promenade combining urban, social, economic, and touristic activities. The research follows an analytical methodology through which the basic urban design theories and standards of infill projects in heritage sites would be reviewed, as well as undergoing a comparative analysis of successful commercialinfill projects in different heritage sites around the world. Moreover, the research would offer an urban assessment of the current urban state of SoorMagra ALthrough cooperating with various governmental entities for acquiring statistical data, maps, and information, as well as a series of fstudies to cover all design criteria. The proposed project aims to integrate a number of different functions including commercial, touristic, and community services through a comprehensive urban design project that acts as a catalyst regenerating project not only in the urban aspect but also socially and economically.

The Gate to Gellerup, Aarhus, Denmark: Steel structures substitute part of concrete building

AbstractThe Gate to Gellerup is one of the first pilot projects in the ambition Master Plan of Gellerupparken. The new innovative solution of constructions creates a new expression and opportunity to connect Aarhus to Gellerup. Not only does the new Gate improve the connection between areas, the new Gate also allows the inhabitants to pass though the building, as the road runs through the buildingThe stairway no. 44 in the block of flats – B4, fig. 1, has been elevated of the ground, to establish the new Infill project. The Infill project contains three stories of flats and a separate stair‐/elevator tower.In order to maintain the architectural expression of the block and of the flats, and due to the long span of the Infill structure as well as a restriction of maximum thichness of the floor slabs, the existing concrete structure has been replaced by a steel structure, as steel is the only feasible material to obtain slender architectural expression.The aim of the steel design was to find a synthesis of architecture, structural behaviour, productivity and buildability. Structural integrity is achieved by extensive analysis using 3D finite element software and the productivity and buildability was achieved by using simple connections and a continuous focus on easy assembly. The project has been designed by use of Tekla 3D‐model software.The steel structure has been designed in a way, which allows the contractor to assemble the whole steel structure on the ground and then hoist it in place as one assembly. This method was developed in order to achieve optimized period of installation on site.

Downtown revitalization in the era of millennials: how developer perceptions of millennial market demands are shaping urban landscapes

ABSTRACT Downtown Phoenix and Houston are changing. They are not dense, historic downtowns; instead, they reflect contemporary downtown growth in sprawling cities. Both cities have reimagined their downtowns, leveraging vacant land, new construction, and infill projects. Through this process, developers are shaping downtown in response to market demand. This research explores how developers in two Sun Belt cities are thinking about Millennials and cementing their preferences into rapidly changing downtowns. We triangulate data from the U.S. Census, regional media, and interviews with 22 downtown development experts. We find developers respond to Millennial preferences in several ways. They are endowing their downtown projects with a greater sense of place and diversity of activities. However, there is a social cost: underlying concerns include rising housing costs and gentrification in the downtowns and reduced demand for housing in the suburbs, particularly if Millennials elect to stay downtown for the long term.

Infill projects and sustainable land use in heritage zones: how to reconcile competing interest sets

<p class="Abstract">Sustainability and heritage are inextricably linked. Heritage conservation helps to build and maintain cultural identity and social cohesion of the city community, especially amongst indigenous residents. Heritage zones in European cities and towns over time have suffered destruction and undesirable urban transitions that alter or remove heritage urban fabric. While architecture and urban heritage aims are generally to promote infill development that retains the integrity of the original structure, communities tend to argue for social values that emphasise the retention of vacant land even if it was originally part of the heritage-built form. Hence, the aim of this paper is to identify city residents’ aspirations in relation to such vacant land and spaces. The paper will investigate the case of Raciborz, a medium-sized city in Southern Poland. It will seek to answer the following questions: 1) Are heritage urban composition and principles of its protection antagonistic to the residents’ aspirations? 2) What are the criteria for classifying and valorising vacant land within a heritage city centre? 3) What is the most appropriate way for city administrations to engage with communities to reconcile competing interest sets? What might be possible educational actions addressed to the communities? In the paper the procedure of identifying and evaluating empty sites in the heritage city centre will be presented as well as the results of survey presenting residents’ ideas of optimal way of use of empty city spaces.</p>

Developers’ price setting behaviour in urban residential redevelopment projects

PurposeThis paper aims to investigate whether developers’ ask lower prices on homes in redevelopment sites than they do on similar units in smaller developments completed over a shorter time span. It also investigates whether developers price units differently at different stages of the redevelopment process. The development of designated redevelopment areas often consists of multiple projects spread across several years, some in parallel, some sequential. New units are put on the market in a piecemeal fashion, and infrastructure, shared green spaces and shared facilities are installed successively.Design/methodology/approachA hedonic price model is used to analyse sales prices of 7,000 new apartments in Oslo sold between 2011 and 2015, all else being equal. The paper distinguishes between infill as one-stage projects, and multi-staged competitive and multi-staged monopolistic redevelopments.FindingsDwellings in redevelopment projects sell at a lower price than similar dwellings in infill projects. In competitive redevelopments, those in charge of the last projects put a slightly higher price on apartments. In redevelopments involving only one developer, the last stages ask the lowest prices.Research limitations/implicationsThis research expands our understanding of developers’ pricing behaviour. Developers supplying housing for the private market through redevelopments land are willing to take risks particularly in the initial stage.Practical implicationsThe findings indicate that credit institutions financing developers’ projects need to take into account the structure of selling prices, including lower prices and higher risk of pursuing redevelopment projects.Social implicationsGaining a better understanding of developers’ pricing behaviour deepens our insights into the dynamics of market-led urban brownfield developments; this knowledge may moreover inform policies on sustainable urban growth.Originality/valueAn original investigation of housing transactions in urban brownfield sites in Oslo provides fresh insights into developers’ pricing behaviour.