Parapet Wall Research Articles

Flow characteristics over flat building roof with different edge configurations for wind energy harvesting: A wind tunnel study

The impact of climate change and global warming makes it imperative to seek sustainable solutions for the built environment. To facilitate the design of future sustainable buildings, wind tunnel tests are conducted in this study to investigate the flow characteristics and wind energy potential over a flat building roof with different edge configurations. Specifically, this study addresses the effect of parapet walls and roof edge-mounted solar panels on the wind flow over a flat-roof tall building. The results show that parapet walls generally slow down the wind speed and increase turbulence intensity as well as skewness angle, which compromises the efficiency of traditional turbine-based wind energy harvesting. On the other hand, the presence of solar panels on the roof edge (or on the top of the parapet wall) further alters flow separation and has the potential to enhance wind energy harvesting over the roof, especially for the solar panel inclined at 30°. In addition to providing valuable data for validating computational fluid dynamics (CFD) simulations, this study could also help to guide the design of wind energy harvesting devices on the building roof and explore the promising synergy with solar panels.

Experimental Comparison Of The Hydraulic Performance Of Overhanging And Vertical Parapets Under Limited Wave Breaking Conditions: The Case Of The New Offshore Ravenna Lng Terminal (It)

Harbors play a pivotal role in global trade, serving as vital gateways for the transportation of goods, fostering economic growth. These essential coastal infrastructures are subjected to relentless forces (e.g. wave action, storm surges, and sea level variation induced by climate change) which can jeopardize their functionality and safety. Safe working conditions are mandatory for the operability of all kinds of harbors. However, particular attention must be paid in the case of terminals dedicated to dangerous goods, as for example Liquefied Natural Gas (LNG). Composite vertical breakwaters may be efficiently used to protect this kind of terminal and have both advantages and disadvantages over rubble mound breakwaters. This work presents the results of a 2D experimental campaign carried out to optimize, from a hydraulic point of view, the parapet wall of the new composite vertical breakwater that will be built to protect the new offshore LNG terminal located in in the North Adriatic Sea in the South-East of the Port of Ravenna (Italy). In particular, two types of parapets walls have been compared: one overhanging (recurved in the shape of one fourth of a circumference with a ray of one meter) and one vertical. For each type of parapets, three different heights were evaluated for a total of six different configurations. The typical water depth in the area where the new terminal will be built is approximately -15.0 m with respect to the MSL and the total range of the astronomical tides does not exceed one metre. The terminal is located about 8.0 km far from the coast and is positioned on a very mild seabed foreshore slope of less than 0.05°

Effect of zeolite and bamboo biochar as CO2 absorbant in concrete

Carbon dioxide (CO2) is one of the major air pollutants that enter the atmosphere. There is a large release of carbon dioxide into the atmosphere as a result of burning fossil fuels in the cement manufacturing industries and many other industries, as well as emissions from gridlock. This increase in CO2 concentration in the atmosphere leads to various ill effects and global warming. To reduce the CO2 level in the atmosphere, efforts were made to prepare concrete that can absorb CO2 by addition of zeolite and bamboo biochar. These materials were chosen because zeolite and bamboo biochar have large pore volume and large specific surface area and so they can absorb more CO2. Zeolite is having more oxygen content and bamboo biochar is having more carbon content which helps in CO2 absorption. In this work, Zeolite is substituted for fine aggregate in the varying ratios of 25% and 50% and bamboo biochar is substituted for cement in the ratios of 0.5%, 1% and 1.5%. The strength properties and CO2 absorbing capacities of various zeolite and bamboo biochar concrete ratios were compared and it was found that concrete with 50% zeolite and 1% bamboo biochar (ZB5) was the optimal mix. The optimal mix was found based on compressive strength, split tensile strength, water absorption, impact strength, amount of CO2 absorption and depth of CO2 penetration in concrete. This optimal mix has a compressive strength of 38.49 MPa which is 7.48% higher than conventional concrete and also has a split tensile strength of 4.39 MPa which is 15% higher than conventional concrete. It was also found that the optimal mix absorbed 1.2 g of CO2 per day and that the depth of CO2 penetration was 15 mm when the concrete cube was kept in the carbonation chamber for 7 days. This study provided necessary information on the addition of zeolite and bamboo biochar in the concrete which enhances both strength properties and CO2 absorption. This study is important because now-a-days the current CO2 emission in the atmosphere is mainly due to several man-made activities. This ZB concrete provides a solution to reduce the amount of CO2 in the atmosphere and can be used in the concrete pavements, sewer pipelines, parapet walls and the environments with higher CO2 concentration and emission.Graphical

Tsunami hazard evaluation of river embankment structures incorporating their vulnerability to seismic strong motion

Development of coastal areas in Japan for various land uses since the 1960s has contributed to industrial upgrades and improved the efficiency of transportation networks. However, there are concerns about the vulnerability of developments on alluvial plains and reclaimed lands to geological events, like ground subsidence due to liquefaction during large earthquakes. Realistic assessment of earthquake and tsunami hazards and evaluation of possible countermeasures require accurate estimation of the amount of subsidence that can be expected from liquefaction at coastal and riverside sites supporting various structures. In this study, to evaluate the amount a river embankment structure might be expected to settle as a result of strong motion from an assumed Nankai Trough great earthquake, we conducted a numerical simulation using the soil–water coupled finite deformation analysis code GEOASIA. We then investigated the effect of the estimated embankment subsidence on tsunami inundation, which was simulated by using nonlinear shallow-water equations and a grid spacing as fine as 3.3 m. The influence of urban structures on the inundated area was taken into account by using a structure-embedded elevation model (SEM). The results showed that subsidence of river embankments and the collapse of parapet walls on top of them would increase both the depth and area of inundation caused by a tsunami triggered by a Nankai Trough scenario earthquake. Our findings underscore the importance of evaluating not only earthquake resistance but also vulnerability of coastal and riverside structures to strong motion in tsunami hazard analyses. Furthermore, the importance of tsunami inundation analysis using a SEM for predicting the behavior of tsunami flotsam in urban areas was demonstrated.

CONFINED-CREST IMPACT: THE INFLUENCE OF THE TOE BERM ON THE IMPULSIVE LOAD CONDITIONS

Composite vertical breakwaters are coastal structures used to defend port basins from waves in intermediate and deep water conditions. In order to safely use the inner side of harbors, it is important to limit wave overtopping. Parapet walls are used for this purpose. To improve the hydraulic efficiency of the parapet wall with a fixed crown wall height, the wall can be shaped giving rise to a recurved overhand toward the sea. Its function is to deflect back the incident waves. Recently, it has been shown that the interaction between non-breaking waves and recurved parapet can induce impulsive pressures due to the confinement of the incident wave crest deflected seaward by the overhanging structure. The new physical phenomenon has been called “Confined-Crest Impact (C-CI)” as shown by Castellino et al. 2018. This physical phenomenon can induce “unexpected” structural failure (Dermentzoglou et al., 2020). More recently, Castellino et al. (2021) extended the Goda’s formulae, which define the maximum pressures along a vertical breakwater, considering the “C-CI” induced by the presence of a recurved parapet. The conducted studies have concerned a vertical breakwater without any berm at the toe of the caisson. The purpose of this research is to extend this last work to a composite vertical breakwater based on a foundation berm.

Investigation laboratory of the effect of increase of the height of the side wall on the performance of nonlinear weirs

ABSTRACT Nonlinear weirs offer a relatively high discharge capacity under low water loads. Their efficiency, however, is decreased at high water loads due to the submergence of the weir outlet key. In the present study, sloping parapet walls with the heights of 2, 4, and 6 cm and lengths of 60 and 30 cm were added to trapezoidal labyrinth weir and piano-key weirs in order to reduce the submergence at the weir inlet. The experiments were conducted in a test flume with a length of 7 m and a width and height of 0.6 m. Results of this study suggested that addition of the sloping parapet walls could reduce discharge coefficient by at least 10% and 13% in Piano-Key Weirs and labyrinth weirs respectively as compared to the control cases. Also, after addition of the parapet walls, Piano-Key Weir outperformed labyrinth weir by up to 19% in terms of the discharge coefficient. The highest efficiency of parapet wall for Piano-Key Weirs was found to be corresponding to parapet wall length and height of 30 cm and 2 cm respectively which differed from that of labyrinth weir of the same parapet wall dimensions by 14%. In fact, the addition of the parapet walls to the labyrinth and piano-key weirs increases the efficiency at high discharges by up to 40%.

Novel Techniques to Study the Effect of Parapet Wall Geometry on the Performance of Piano Key Weirs

Piano key weirs (PKWs) with crown parapet walls effectively manage water levels and maximize storage. However, their efficiency is compromised by interactions between water flow and submerged outlets during rising water levels. This study investigates novel parapet wall designs to improve PKW performance and reduce submergence effects. The experiment focuses on a PKW with a fixed 12.6 cm weir height. Three parapet wall configurations are tested: Mode 1 (walls on all apex), Mode 2 (walls fixed on sides and inlet), and Mode 3 (walls along the sides). Each mode includes three parapet wall profiles: rectangular (consistent form), triangular, and trapezoidal (varying characteristics). Results indicate that parapet wall design significantly affects water level variations with increasing wall height. Mode 3, featuring triangular and trapezoidal parapet walls, demonstrates the highest discharge capacity among the examined profiles. The discharge coefficient correlates with parapet wall height and form. Notably, the triangular wall in Mode 3 outperforms Modes 1 and 2 when parapet walls maintain an R/P ratio of 0.36. This study introduces innovative parapet wall designs to enhance PKW efficiency. By implementing advanced configurations, significant improvements in water control and discharge capacity can be achieved. These findings contribute to the state-of-the-art in PKW technology and offer valuable insights for practical engineering applications.

Soft touch temporary works: Westminster Hall roof lantern freestanding access, UK

The temporary access scaffold for refurbishing one of the Westminster Hall roof lanterns at the Palace of Westminster in London, UK, required a particularly sensitive approach. The only means of support, other than scaffold towers 38 m apart at ground level, were two awkward-shaped parapet walls. Removing the capping stones of these walls would be a health and safety risk and unsympathetic to the historic listed building. Standing over 45 m high with a main bridged span of 25 m, the scaffold was stabilised without the need for a single intrusive fixing. It was supported directly off existing parapet walls in such a way that no trace of the scaffold was left after 3 years in use.

Numerical Study on Hydraulic Characteristics and Discharge Capacity of Modified Piano Key Weir with Various Inlet/Outlet Width Ratio

A modified piano key weir with a rounded nose and a parapet wall (MPKW) can improve the discharge capacity significantly compared to a standard piano key weir. However, the optimum of the inlet/outlet width ratio (Wi/Wo) on the discharge efficiency of MPKW is still not investigated numerically. The present work utilized the numerical modeling to investigate and analyze the effects of the inlet/outlet key width ratios on the hydraulic characteristics and discharge capacity of the MPKW. To validate the numerical model with the experimental data, the results indicate that the average relative error is 2.96%, which confirms that the numerical model is fairly well to predictthe specifications of flow over on the MPKW. Numerical simulation results indicated that the discharge capacity of the MPKW can be improved up to 8.5% by optimizing the Wi/Wo ratio ranging from 1.53 to 1.67 even if the other parameters of the MPKW keep unchanged. A big Wi/Wo ratio generally leads to an increase in discharge capacity at low heads and a little effect on the discharge efficiency at high heads. The discharge efficiency of the inlet and outlet crests increases up to 9.6% for high heads, while discharge efficiency of the lateral crest decreases up to 23.5% compared with the reference model. The findings of the study revealed that the intrinsic influencing mechanism of the Wi/Wo ratio on the discharge performance of MPKWs.

NATURAL PROCESSES AS JUSTIFICATION FACTORS FOR DECISIONS ON PORT HYDRAULIC STRUCTURES

The effects of sea waves and currents on harbour hydraulic structures are analysed from published open source data and the characteristics of scour from waves, including tsunami waves, are considered. Local bottom scour threatening the general stability of gravity-type engineering structures can arise under the effect of storm waves and currents, jets from ship propulsion devices and tsunami waves near hydraulic engineering structures. The types of scour mechanisms from sea waves have been investigated, i.e., local, general, and overtopping scour. There is a lack of sufficient measurement data for general scour to verify the calculation methods. Generally, general scour does not damage a structure, although it can contribute to its destruction by other types of scour when they overlap. Therefore, existing studies mainly focus on the analysis of local scour. The relationship between local scour and ground liquefaction and their influence on the stability of marine hydraulic structures is established. Failure mechanisms of hydraulic structures due to erosion by tsunami waves are analyzed: leeward and seaward toe scour, crown armour failure, parapet wall failure, sliding failure. The tsunami wave scour enhancement parameter is given, which is the fraction by which the pore pressure gradient reduces the frictional forces resisting scour. Significant ground instability occurs when the scour amplification parameter Λ exceeds a value of 0.5 (Λ ≥ 0.5). The parameter Λ can be used to assess areas where instantaneous liquefaction may be responsible for scour and sediment movement and to further recalculate erosion depths obtained without considering liquefaction. Liquefaction from a tsunami wave may penetrate up to 28% of the maximum erosion depth due to shear forces. The liquefaction phenomenon may occur due to a sudden drop in the water level in the area of return flow concentration. Consequently, the liquefaction phenomenon must be considered in the stability and erosion analysis around the structure.

Design and selection of alternative embankments to overcome tidal flood (A case study of the construction plan of a tidal embankment at Sayung, Demak)

Tidal embankment project in Sayung is one of the construction planning projects of the government. There are three alternatives of embankment designs that may be applied in the construction project; (1) Parapet Wall and Corrugated Concrete Sheet Pile (CCSP) reinforcement, (2) Concrete Wall Embankment with mini pile reinforcement, and (3) Multipurpose Panel System Embankment (SPS). The research was needed to examine the designs to find the fittest. This study aimed to redesign the construction plan of the tidal embankment using Plaxis software. This software was to analyze and determine the safety factors of the three alternative embankment designs. It was stated to be safe because it exceeded the standard of 1.5. One of the three alternative embankments was implemented using the Analytical Hierarchy Process (AHP) method based on predetermined criteria: (1) Aspects of function and benefits, and (2) Aspects of site conditions which include cost and construction process. From the alternative selection using the expert choice program analysis method, the concrete wall embankment with mini-pile reinforcement was the main priority, with a weight value of 45.9%. Meanwhile, the second priority was the Parapet Wall and CCSP Reinforcement with a weight value of 37.2%, and the third choice was the Multipurpose Panel System Embankment (SPS) with a weight of 17%.

Behaviour of Glass Fibre Reinforced Gypsum panels as Walls: An Update on the Recent Research Developments

The current housing shortage problem in the country, especially among the low-income groups and the necessity to address their shelter needs, led to the introduction of Glass fibre reinforced gypsum (GFRG) panels in India. These panels were originally developed in Australia in 1990 and later introduced in India, China, Hong Kong and other countries. They are light-weight, load-bearing walls used for rapid construction of affordable and eco-friendly houses (individual units to multi-storeyed buildings) and are being used in India for more than a decade. These are prefabricated in controlled-conditions in factories, from gypsum plaster reinforced with glass fibres along with certain special additives and are available in a fixed size of 12 m length, 3 m height and 124 mm thickness. The panels are hollow, with cavities of size, 230 × 94 mm, aligned along the height. These panels can resist axial, in-plane and out-of-plane loads and various studies conducted worldwide established the suitability of the panel for the construction of walls, slabs, staircases and parapet walls. GFRG buildings consist of GFRG panels as walls and slabs (without any beams and columns) and can be constructed up to 5-8 storeys in low to moderate seismic zones, and lesser height in higher seismic zones. Thus to properly understand the structural behaviour of the GFRG building system and to develop a proper design guideline, comprehensive research works were undertaken in India and other countries which includes the study to determine the various material and structural properties of the panel and this paper presents a critical review of the experimental and theoretical investigations on the structural behaviour of GFRG wall panels.

Visualized Failure Prediction for the Masonry Great Wall

The cultural, architectural, and historical heritage value of the Great Wall of China drives the need to maintain, rehabilitate, and restore its structural integrity from artificial and natural damage. In this study, a hybrid architectural visualization and structural collapse simulation of the Ming Great Wall (1368–1644 AD) are conducted in Blender based on the unit blocks and a physics engine (i.e., Bullet Constraint Builder). Visualized failure predictions caused by four damages, i.e., stone layer collapse, step collapse, parapet walls inward tilting, and stone layer bulge, are developed and performed on a strength basis. The main input parameters are brick dimensions, friction coefficient, and adhesive/glue strength, while the primary output includes collapse, and global and local stabilities. Finally, the results show that the combination of unit blocks and a physical engine can visually simulate the occurrence process of the Great Wall’s failures with preliminary engineering outcome, especially those related to collapse, and can also predict the adverse consequences of the precipitating factors.

Investigation of convective heat transfer at the facade with balconies for a multi-story building

As a common building appendage, balconies can significantly alter the flow pattern near the building façade, thus greatly affecting the convective heat transfer coefficient (CHTC) of façades. In the present study, computational fluid dynamics (CFD) simulations are performed with the 3D steady Reynolds-averaged Navier-Stokes (RANS) SST k-ω model to evaluate the convective heat transfer at the building façade with balconies. This model is systematically validated by a reduced-scale wind tunnel experiment and then utilized to conduct simulations with high-resolution grids. The effects of the balcony height (height of balcony parapet walls), depth, and length on the forced convective heat exchange at the façade and balcony surfaces are analyzed in detail. The results show that with the presence of balconies, the surface-averaged CHTC (CHTCavg) is reduced by about 17.5% at the windward facade, while it is reduced by 35.2% at the leeward façade. Furthermore, when the height of the balcony (Hp) varies from 0.5 to 1.5 m, CHTCavg decreases by up to 39%, 48.8%, and 50% on the leeward facade, the inner surfaces of windward and leeward balconies, respectively. However, balcony depth and length have relatively non-significant effects on the CHTCavg of building facades and balconies' surfaces. Finally, new correlations are established to describe the average CHTC along the façade and balconies’ surfaces. The difference in CHTCavg obtained from the correlations and the simulations is less than 6%. The findings of the present study would facilitate the calculation of the cooling and heating loads of buildings with balconies.

Numerical modelling of breaking wave impact loads on a vertical seawall retrofitted with different geometrical configurations of recurve parapets

Abstract Experiments are the traditional techniques used in coastal engineering to study complex wave structure interactions. However, with the advent of high-performance computing, even performing 1:1 scale numerical simulations has become a reality. The progress aids in extending the parametric investigation or repeating the procedure for comparable structures. In this study, a numerical model in OpenFOAM® with waves2Foam wave boundary conditions is used to simulate wave structure interactions at seawalls with varied geometrical configurations of recurved parapets. The numerical model is validated by employing ForschungsZentrum Küste (FZK)'s large-scale (1:1) experiments. The validated model is then applied to the plain parapet and vertical wall to understand better overtopping behaviour, pressure distribution, and structural loads. Numerical modelling is used in this study to visualise and assess intrinsic parameters such as the velocity profile, vorticity, air entrapment, and entrainment better to understand the dissipation characteristics of seawalls with recurved parapets.

Evaluation of Maintenance Procedures for Bridge Spalling on Parapet Walls

Parapet wall deterioration concerns the Ohio Department of Transportation as well as other transportation agencies. The spalling of parapet walls presents a danger to the traveling public, as pieces of deteriorated concrete may fall onto the road below. The current repair method is to chip off the weakened concrete using pneumatic chipping hammers. However, this process not only damages the sound concrete, but it also leaves an unprotected surface. This project implemented hydrodemolition as a means of removing spalled concrete. A hydrodemolition robot was utilized in the field to remove concrete on the interior and exterior face of a parapet wall. This method was determined as promising as it does not damage the sound concrete surface and exposed reinforcing steel, it mitigates silica dust, and it efficiently removes unsound concrete. Polyaspartic polyureas are a concrete protectant/sealant that may be rolled onto a prepped concrete surface using a paint roller. This material not only seals the concrete but may provide a reinforcing barrier that retains loose pieces of concrete. This material was used to coat several parapet walls in the field, and it was observed that three of the five polyaspartic products appeared effective in the field at providing a protective barrier. In contrast, all were equally effective in laboratory testing.

Effect of hanger system on resistance against progressive collapse of RC buildings under column removal in alternate storeys

Progressive failure refers to the continuous disintegration of a structure until partial or complete collapse, resulting in severe economic losses and mass casualties. The present study proposes a feasible solution against progressive collapse by the introduction of a hanger system and highlighting its effect on R.C. building under the progressive collapse scenario. The hanger system mainly comprises of a structural wall enacted at the terrace level in place of the parapet wall, which acts as a highly stiff member connecting the columns in various bays and allowing load transfer between these bays, thus creating an alternate path for loads. This study follows the removal of various critical columns on the alternate storeys, in contrast to previously conducted researches which were focused on only removing selected columns on the ground storey. CSI's ETABS 19 software has been used to simulate the progressive collapse of a reinforced concrete building, assessing the behaviour of a 10 storey reinforced concrete building under progressive collapse, with and without designing structural wall at the parapet, using static linear analysis of progressive collapse compliant with the general service administration guidelines (2016). In all the cases of removal of critical columns, the results are compiled in respect of DCR values (Demand Capacity Ratio) at critical locations and joint displacement at the top of removed columns. The hanger system used in this study provides an innovative and feasible solution to prevent progressive collapse by providing alternate load paths and increasing the robustness of the building.

Malacca's “Straits Chinese traditional courtyard eclectic style shophouses”: facades' architectural design elements through place identity

PurposeThe traditional courtyard shophouses modifications, alterations and deterioration over the years have become a source of concern to major stakeholders. In George Town World Heritage Site Malaysia, studies have shown that the worst hit among its various shophouses are the Straits Chinese traditional courtyard eclectic style shophouses. This paper investigates the traditional courtyard shophouses concerning the role of architectural formation design components, and how this can sustain the place identity of the Straits Chinese typology.Design/methodology/approachThe methodological approach regards the collection of data and analysis of 30 face-to-face interviews and the observation of Lots number 3, 5 and 7, located along Lorong Ikan, George Town World Heritage Site.FindingsIt was found that these Lots express the place identity of the Straits Chinese, and its major exterior architecture components to be observed are the column head (Chi Tou) capital, parapet wall, bressummer beam and ionic column, and gable and gable ends.Research limitations/implicationsThis paper is limited to the role of architectural formation design components. Future research is needed to expand the scope of participant elements via a quantitative approach. This will enhance the validation of findings from this paper.Practical implicationsIt is recommended the use of the proposed checklist to enhance the sustainability of the architectural components regarding the place identity of these styles of shophouses, which provides salutary lessons on how to preserve the heritage buildings. Also, major stakeholders with leading evidence from relevant government agencies should ensure the preservation of these cultural and heritage buildings for the next generation.Social implicationsThis paper found that the family beliefs and social impact were the components that express the place identity of the Straits Chinese.Originality/valueThis paper demonstrates that the role of architectural formation design components regarding place identity of Straits Chinese traditional courtyard eclectic style shophouses cannot be over-emphasised.

CFD analysis of the impact of geometrical characteristics of building balconies on near-façade wind flow and surface pressure

The presence of building balconies can significantly modify the near-façade wind flow pattern and surface pressures. The present study evaluates the impact of building balcony geometry on mean wind speed on balcony spaces and wind-induced mean surface pressure for generic high-rise buildings. The focus is on balconies that extend along the entire width of the building façade. Large-eddy simulations (LES), validated with wind tunnel experiments, are conducted to investigate the impact of (i) balconies present or not, (ii) balcony depth, (iii) balcony parapet walls, (iv) balcony partition walls, and (v) density of balconies. The results indicate that the balcony geometry can greatly affect the mean wind speed on balcony spaces and the local and façade-averaged mean pressure coefficient (Cp). The presence of balconies can increase the façade-averaged Cp over the windward and leeward façades by 5.2% and 8.9%, respectively. These numbers rise to 23.5% and 23.3% when two partition walls are added at the lateral edges of the façades. Adding five partition walls can reduce the overall area-averaged wind speed on balcony spaces by 68.0% compared to the case without partition walls. These findings can be useful in developing, designing and constructing buildings with façade geometrical details that improve building ventilation, air quality and wind comfort.

High Reynolds number aerodynamic testing of a roof with parapet

Aerodynamic testing was executed on a large-scale building with two distinct aspect ratios (1:6 and 1:3), at a large open-jet facility, Louisiana State University (LSU). To illustrate, a 1:15 scale test model was extensively investigated by experimental testing at a high Reynolds number (~2.3 × 107). The objective was to understand the performance of parapets in reducing the magnitude of localized and area-averaged roof pressures. Through analogy with bare-roof and several parapet configurations, the paper explores the performance of parapet walls and why they can be employed in aerodynamic mitigation. The results suggest installing a parapet wall will act as an aerodynamic mitigation device to reduce negative (uplift) loads. Large-scale testing indicates that the taller the parapet, the higher the reduction in mean and fluctuating pressures. However, depending on the roof’s aspect ratio, there is an optimal parapet height. The study concludes that 40–50% reductions in roof pressures can be achieved with parapets. Along the same lines, to yield high reductions in roof pressures, the parapet height is a key parameter. Short parapets may have low performance under conical vortices. The importance of the current study is that parapets, as well as other architectural features, are widely considered difficult to investigate by small-scale testing, at low Reynolds numbers, the leading cause of discrepancies between the laboratory and field measurements. Consequently, the current paper contributes to knowledge useful to explain the role of parapets in reducing aerodynamic pressures, for buildings to withstand wind loads at high Reynolds numbers.