Pedestrian Perceptions of Sidewalk Paving Attributes: Insights from a Pilot Study in Braga

Abstract

The influence of sidewalk paving materials on pedestrian safety and comfort remains an underexplored topic within the walkability literature. This pilot study aims to address this gap by evaluating the role of five surface-related attributes—roughness, friction, texture, heat retention, and maintenance—through a qualitative approach complemented by a simplified quantitative evaluation. The study was conducted along a pedestrian route in Braga, Portugal, where pedestrian perceptions were collected via a questionnaire and compared with objective measurements obtained at seven testing points with different paving materials. The results indicate a strong preference for concrete and mortar pavements due to their slip-resistant surfaces, smoothness, and overall regularity. Quantitative tests confirmed that these materials exhibited the highest slip resistance and surface regularity, reinforcing the general alignment between pedestrian perceptions and measured performance. Participants rated paving attributes higher than others, such as sidewalk width or obstacle-free paths. Notable demographic differences also emerged: women rated sidewalk attributes more highly than men, seniors preferred traditional stone pavements more, and adults favored concrete. These findings highlight the importance of integrating surface-related sidewalk attributes into walkability assessments and urban design strategies to promote safer, more comfortable, and more inclusive pedestrian environments.

1. Introduction

Developing walkable cities is essential for creating sustainable, equitable, and accessible urban transport systems for all citizens [1]. Pedestrian-friendly settings are considered crucial for developing walkable and healthy communities. Walkability, defined as the extent to which the built environment supports and encourages walking, is influenced by various factors, including land use density and diversity, accessibility to destinations, street connectivity, traffic safety, public security, streetscape design, and pedestrian infrastructure characteristics [2]. These attributes determine whether walking is a convenient, comfortable, connected, safe, and attractive mode of transport compared to others [1,3]. Assessing walkability features is crucial in assisting policymakers and urban planners in developing pedestrian-friendly cities. Most of these evaluations rely on walkability indexes, composite measures that sum and weight various built environment attributes influencing walkability [4]. The growing availability of spatial data at the neighborhood level, such as residential density, land use mix, street connectivity, and advancements in Geographic Information Systems (GISs), has led to the rising number of these indexes in recent years [5,6]. However, these metrics have often not included microscale attributes related to streetscape design and pedestrian infrastructure due to a lack of street and sidewalk-level data [7,8].

Pedestrian infrastructure includes sidewalks, crossings, pedestrian tunnels and bridges, ramps, stairs, trails, shortcuts, and other formal and informal paths legally accessible to pedestrians [1]. Among these, sidewalks are the most significant, providing safe, dedicated spaces for pedestrian movement and interaction within the public right-of-way, separated from roadway vehicles [9]. Typically paved and elevated above the street level to protect pedestrians and provide a clear pathway [10], sidewalks represent an important share of the urban space, accounting for approximately 5% to 7% of the total paved surface in various cities [11]. Because of their ubiquitous presence and multifunctional role, sidewalks are important urban public spaces facilitating pedestrian mobility while serving as social and economic spaces for street-level commerce, community activities, leisure, and physical activity.

The literature confirms that pedestrians are very sensitive to sidewalk conditions, significantly influencing their mobility choices [12,13]. The presence and quality of sidewalks determine whether people feel attracted, discouraged, or deterred from walking [13]. The absence of sidewalks forces pedestrians to use roadways, increasing the risk of accidents. For example, the study by Abou-Senna et al. [14] revealed that pedestrian crashes along roadways are 1.67 times more likely in areas without sidewalks. The usability and pedestrian-friendliness of sidewalks, when present, are shaped by multiple factors, including the pavement surface; width; obstructions; slope; street furniture; street trees; lighting; and accessibility features, such as curb ramps and tactile paving [2,15]. Among these, the pavement surface is one of the most critical attributes influencing pedestrian safety and comfort [16]. Pedestrian safety encompasses various dimensions, including the following:

• Public security: Ensuring pedestrians feel free from crime or harassment [2];
• Risk of collisions: Mitigating conflicts with motor vehicles, bicycles, and other road users, as pedestrians are more vulnerable [2];
• Infrastructure-related safety: Preventing injuries unrelated to vehicle collisions, like falls or other incidents caused by uneven or hazardous walking surfaces [17].

Surprisingly, recent studies highlight that infrastructure-related falls cause more pedestrian injuries than traffic-related incidents but receive less research attention [17], and there are no audit tools to assess sidewalks from the aspect of safety from falling [18]. Pavement surface conditions, such as material type, maintenance, and cleanliness, are critical to pedestrian safety by affecting stability and traction and, thus, preventing infrastructure-related accidents [15]. Hazards such as uneven surfaces, cracks, and slippery materials may force pedestrians to walk onto the roadway, increasing their exposure to vehicle collisions [19]. The literature confirms that most outdoor pedestrian falls are related to hazardous pavement conditions, including uneven or damaged sidewalks (e.g., broken, raised, loose-brick, or cracked surfaces) [13,20] and slippery surfaces (e.g., low-friction or wet materials) [21,22,23], which increase the risk of trips and slips [23,24]. Poor sidewalk conditions are particularly problematic for vulnerable populations, such as older adults and individuals with mobility impairments [3,25]. In contrast, well-maintained sidewalks encourage higher pedestrian activity [26].

Besides safety, sidewalk paving materials and maintenance significantly affect pedestrian comfort, encompassing factors that create a pleasant and suitable walking experience [1], including stability, shock absorption, and aesthetics. These factors influence emotional responses, such as relaxation, ease, and enjoyment experienced during a walk. Smooth and even surfaces minimize physical strain and enhance pedestrian comfort, while poorly maintained, irregular, and slippery surfaces contribute to discomfort and accident risks [19,24]. Pedestrian thermal comfort is another critical factor when evaluating sidewalk paving materials, especially in hot climates. For instance, dark materials, such as asphalt, absorb and retain solar heat, increasing sidewalk temperatures and causing discomfort, especially on streets lacking adequate shading [27,28,29]. Conversely, light-colored reflective materials reduce heat retention and sidewalk temperatures but may cause glare-related visual discomfort on sunny days [29].

Despite the significant impact of sidewalk paving materials on pedestrian safety and comfort, this topic remains underexplored, and these attributes have rarely been included in walkability evaluations [2,30] for various reasons. First, research on sidewalk infrastructure is limited due to a generalized lack of publicly available data on sidewalk conditions [7,8,31,32]. Most cities do not systematically collect data on sidewalk material types, conditions, and maintenance [13,22]. Although recent advancements in data collection, such as machine learning [22,33] and mobile-based assessments [34,35], have improved evaluation methods, sidewalk data remain incomplete, inconsistent, or unavailable on the city scale, limiting its integration into comprehensive walkability assessments. Second, most paving studies focus on roadways rather than sidewalks, and cities lack technical guidance for sidewalk policy and management [32]. As a result, the influence of specific sidewalk paving attributes, such as surface irregularity and friction, on pedestrian safety and comfort remains underexplored. The lack of adequate items for assessing the sidewalk condition and maintenance and insufficient factors for evaluating fall-related safety is further supported by Aghaabbasi et al. [18]. Third, limited research combines technical evaluations with qualitative assessments of pedestrian perceptions [36]. Since user perceptions can complement objective measures, surveys offer valuable insights into walking experiences [17] and attitudes toward sidewalk pavement quality [37]. Incorporating this feedback into walkability frameworks can improve infrastructure prioritization and support the design of more inclusive public spaces.

This pilot study investigates pedestrian perceptions and objective evaluations of five specific sidewalk paving materials and their impact on pedestrian safety and comfort to address the identified knowledge gaps. Using a questionnaire administered along a pedestrian route in Braga, Portugal, the study examines three key aspects:

• Preferred sidewalk paving materials and the reasons for such preferences.
• The importance of five specific paving attributes—roughness, friction, texture, heat retention, and maintenance—for pedestrian safety and comfort, as well as the alignment between perceived conditions and measured performance.
• Pedestrian evaluations of sidewalk paving conditions along the route.

The study also examines broader sidewalk attributes—such as width, obstructions, street furniture, tree presence, and curb ramps—to determine whether these general characteristics are perceived as more or less influential for pedestrian safety and comfort than surface-related paving attributes. The study offers valuable insights for urban planners and researchers by comparing these two categories, highlighting the importance of integrating surface quality into walkability assessments to support safer and more inclusive pedestrian infrastructure.

Objective measurements were conducted at selected points along the route to complement the subjective evaluations gathered through the questionnaire. These included standardized tests and visual inspection to assess four physical attributes—roughness, friction, texture, and heat retention—along with the observed maintenance condition of the surfaces. This complementary quantitative evaluation enables a direct comparison between measured and perceived conditions, reinforcing the interpretation of pedestrian feedback and offering an empirical basis for understanding how paving materials influence comfort and safety.

Figure 1 presents the conceptual framework that guided the study and illustrates its overall scope and structure. It distinguishes two categories of sidewalk attributes: surface-related attributes and general sidewalk characteristics. The former were assessed through objective methods (tests and inspection) and subjective ratings (questionnaire), while the latter were evaluated only through pedestrian perceptions. The framework also highlights how the various sidewalk attributes relate to two key outcome dimensions of this pilot study: perceived pedestrian safety and comfort.

2. Materials and Methods

2.1. Study Design

This research was designed as an exploratory pilot study to investigate perceptions of sidewalk paving attributes concerning pedestrian safety and comfort. Exploratory research is particularly valuable for addressing topics with limited existing knowledge, as it enables researchers to explore emerging areas of interest and uncover new insights. Prior studies highlight that this approach is critical for investigating complex, understudied phenomena, allowing participants to share their perspectives and contribute to a deeper understanding of the field [38]. Therefore, this study is an initial exploration of how individuals perceive specific sidewalk paving attributes and their impact on walking comfort and safety.

This study also incorporated a quantitative field-based evaluation of sidewalk surface attributes to enrich the analysis and provide a broader perspective. This complementary approach enabled the comparison of subjective perceptions with objective surface performance indicators, reinforcing the relevance of pedestrian feedback within an urban infrastructure context.

2.2. Study Area

A pedestrian route in Braga, Portugal, between the Bus Central Station (BCS) and the University of Minho (UM), was selected to examine how pedestrians perceive pavement attributes and their influence on walking safety and comfort. As shown in Figure 2, the 3.0 km route connects BCS with the Gualtar Campus of UM.

This route was chosen for its diverse conditions. First, from an urban perspective, it connects the city center to newer urban fringes, linking areas with varying land uses and densities, including residential, retail, public, cultural, and tourist spaces. The city center includes a well-preserved heritage site with medieval history, Roman vestiges, and notable monuments and buildings reflecting Portuguese architecture from the 15th to 19th centuries. In contrast, the northeastern sector is predominantly residential, housing major educational and healthcare facilities, including UM and Braga’s hospital.

Second, the route includes various paving materials representing the city’s sidewalks, reflecting common design choices and construction practices. The selected route is paved with different materials, including granite blocks (cobblestones), mortar, granite stone slabs, Portuguese pavement, concrete blocks, and concrete hexagons (Figure 3). Specific streets, such as Conselheiro Januário Street, have a mix of paving materials, including stone slabs, Portuguese pavement, concrete blocks, and mortar. Concrete is the most prevalent paving material along the route, covering substantial portions of the pathway. Specifically, concrete hexagons account for 32%, while concrete blocks comprise 17% of the total route length. The other sidewalk materials used in the route include mortar (29%), granite stone slabs (14%), granite blocks (6%), and Portuguese pavement (2%). Ferreira [39] also noted that these sidewalk paving materials are the most frequent in Portugal. Pedestrian crossings and overpasses were excluded from the analysis, as this study focuses specifically on sidewalk pavements.

Third, it features a range of sidewalk characteristics that reflect different phases of urban development and evolving paving techniques. This range includes recently improved sidewalks and sections with noticeable distress, such as cracked, uneven, and broken surfaces (Figure 4), representing a wide range of pavement maintenance conditions relevant to assessing the pedestrian experience. For instance, while Nova de Santa Cruz Street’s sidewalks have been recently improved, some areas still exhibit pavement deterioration.

The three aforementioned reasons make the selected route a suitable case study for understanding how pedestrians perceive the effects of the paving attributes on pedestrian safety and comfort.

2.3. Subjective Evaluation (Qualitative Data Collection)

A face-to-face questionnaire was administered along the selected route to gather individuals’ perceptions of how sidewalk attributes influence pedestrian safety and comfort. Questionnaires are effective for collecting pedestrian opinions on walking conditions [36]. In this pilot study, participants were approached and invited to participate in the survey as they were found along the route, based on their presence and availability. This method was chosen to ensure real-time engagement with pedestrians using the sidewalk. The full questionnaire used in this study is available in the Supplementary Materials (File S1), ensuring transparency and allowing replication of the data collection process.

2.3.1. Organization of the Questionnaire

The questionnaire comprised 24 structured, closed-ended questions (single-choice, multiple-choice, or ranking), categorized into four sections to assess pedestrian perceptions systematically:

• Demographic data (e.g., gender, age, and disabilities affecting walking) and pedestrian profiles (e.g., walking frequency and purpose).
• Preferences regarding sidewalk paving materials and corresponding reasons.
• Evaluation of sidewalk attributes, including paving materials’ type, condition, and overall sidewalk characteristics. Participants ranked each walking attribute using a five-point Likert scale (1 = “not important” to 5 = “very important”).
• Assessment of sidewalk paving attributes along the route for each survey location. Again, pedestrian perceptions of paving conditions along the route were ranked using an identical five-point Likert scale.

2.3.2. Paving Attributes Assessment

The reasons below explain why the following five paving attributes were assessed in this pilot study (survey Section 3 and Section 4).

• Roughness: Measures the pavement’s smoothness and regularity. Uneven surfaces with cracks, raised edges, or broken areas increase pedestrian fall risks and walking discomfort [13,20].
• Friction: Evaluates slip resistance in the interaction between the sidewalk surface and the footwear [40]. Depending on material characteristics, slip resistance decreases over time due to surface wear, polishing, and weathering. Low-friction sidewalks increase pedestrian fall risks, particularly for elderly individuals [21,22,23].
• Texture: Influences surface drainage, skid resistance, and smoothness, thus impacting pedestrian safety and comfort [20,41]. The surface texture depends on the materials and the joints between blocks or stones. While rougher surfaces provide better water drainage in wet climates, like that of Braga, with rainy autumns and winters [42], they may be less comfortable, particularly for wheeled mobility aids.
• Heat retention: Affects pedestrian thermal comfort, especially in hot summers [28,29], being influenced by shading (e.g., vegetation and buildings), microclimate conditions, and the sidewalk materials’ type and color [27,28]. Dark materials, such as asphalt, retain more heat, causing discomfort, whereas light-colored materials reflect solar radiation and absorb less heat but may cause glare [29].
• Maintenance: Poor maintenance results in hazardous, uncomfortable, and aesthetically unappealing sidewalks to pedestrians [12,15,43]. Contributing factors include lack of regular maintenance operations, adverse weather, collisions, unsuitable street furniture, substandard materials, heavy pedestrian traffic, and inadequate sidewalk cleaning [12].

2.3.3. General Sidewalk Characteristics Assessment

The questionnaire also assessed the following five broader sidewalk attributes influencing pedestrian safety and comfort:

• Sidewalk width: Ensures enough space for safe pedestrian movement without obstruction or collision, particularly in high-traffic areas. A minimum of 1.5 m is recommended for accessibility and to meet diverse pedestrian needs [1,15].
• Obstacle-free path: Physical obstructions or hazards, such as improperly parked vehicles and some street furniture, can hinder pedestrian movement, particularly for those with mobility impairments [1,12]. Thus, unobstructed sidewalks are essential to ensure all users’ safe and free pedestrian movement.
• Street trees: Provide shade, cooling, and UV protection while improving the aesthetic appeal and the sense of enclosure of sidewalks. Therefore, they improve pedestrian thermal comfort in hot climates and foster a more pleasant environment [1,2,15].
• Street furniture: Includes benches and other amenities that enhance pedestrian comfort and encourage social interactions in public spaces. Thoughtfully designed and well-placed furniture can reduce fatigue and encourage walking [1,44].
• Curb ramps: Facilitate accessibility for wheelchair users, strollers, and individuals with mobility challenges. These smooth transitions, for example, at crossings, eliminate tripping hazards, making urban areas safer and more inclusive [15].

2.3.4. Further Information on Data Collection

Simplified explanations were provided for each attribute under evaluation to ensure that participants understood the technical terminology used throughout the questionnaire. These descriptions were carefully adapted to make the concepts accessible to a general audience and were supported by illustrative images to reduce interpretation errors.

For surface-related attributes, roughness was described as how uneven or bumpy the pavement feels while walking, while friction referred to how slippery the surface might be, particularly in wet conditions. Texture was explained as the overall smoothness of the surface, including the presence of joints, and how it influences water drainage and walking comfort. Heat retention was introduced as the amount of heat the pavement absorbs during the day, affecting thermal comfort. Finally, maintenance was described in terms of visible conditions, such as cracks, patching, or dirt, reflecting the overall upkeep of the surface.

Similar simplifications were made for the broader sidewalk characteristics. Sidewalk width was referred to as the availability of at least 1.5 m of obstacle-free walking space. Obstacle-free paths were defined as areas without physical barriers, such as parked vehicles or street furniture. Street trees were described as lining at least one side of the street, contributing to shade and thermal comfort. Street furniture was depicted as benches, bins, or other items that improve pedestrian convenience. Lastly, curb ramps were explained as lowered transitions at crossings or entrances that facilitate accessibility for wheelchair or stroller users.

Before the final application of this survey, a preliminary test was conducted with a small group of participants to evaluate the clarity and usability of the questionnaire. Based on the feedback received, minor adjustments were made to improve the instrument’s reliability and effectiveness in capturing relevant data.

A researcher (AR) administered the final questionnaire in person to ensure that participants fully understood the technical aspects of the questions. This approach facilitated real-time clarifications for participants’ uncertainties about the sidewalk attributes, which might be challenging to grasp online. Potential participants were approached along the selected route and invited to participate in this pilot study. Surveys were conducted on weekdays between 5 May and 21 June 2023, from 9 a.m. to 6 p.m., with each session lasting approximately 15 min. As the weather conditions influence pedestrian perceptions [45], it is important to present an overview of the weather in Braga during the survey period. As shown in

Table 1. Weather conditions in Braga during the data collection period.

Parameter	Minimum	Maximum	Average
Temperature (°C)	7.4 (14 May)	31.0 (7 June)	19.0
Precipitation (mm/m2)	0.0 (27 days)	54.0 (9 June)	4.5
Relative humidity (%)	31.0 (18 May)	91.2 (10 June)	62.5
Wind speed (km/h)	6.1 (30 May)	63.7 (27 May)	9.9
Solar radiation (W/m2)	-	1425 (11 June)	-

Source: Braga Meteorological Station [46].

, the weather conditions in Braga during this period varied considerably. The average temperature was 19.0 °C, with a minimum of 7.4 °C recorded on 14 May and a maximum of 31.0 °C on 7 June. Precipitation levels fluctuated, with 27 days recording no rainfall, while the highest daily total reached 54.0 mm on 9 June. The average precipitation was 4.5 mm. Relative humidity ranged from 31.0% on 18 May to 91.2% on 10 June, with an overall average of 62.5%. Solar radiation reached a maximum of 1425 W/m² on 11 June.

2.4. Objective Evaluation (Quantitative Data Collection) of Sidewalk Surface Attributes

The subjective assessment was complemented with a quantitative evaluation of surface-related sidewalk attributes conducted at seven testing points along the pedestrian route, as illustrated in Figure 2. These points were selected based on the type of paving material and the diversity of surface conditions, aiming to represent the areas where the pedestrian surveys were conducted. The following attributes were evaluated using standardized or widely accepted field methods:

• Roughness was measured using a 3 m straightedge test to assess longitudinal unevenness and geometric surface irregularities. A laser sensor mounted on the straightedge moved along its entire length to measure the vertical distance to the surface. Three repetitions were performed at each location, and the mean deviation was calculated. Similar methodologies have been used in previous studies on pedestrian infrastructure [47].
• Friction was evaluated with the British Pendulum Tester (BPT), a standard method to characterize the slip resistance of walking surfaces under wet conditions. This equipment simulates heel strike via a rubber slider, translating the resulting energy loss into a BPT value. According to the literature [20], BPT values above 35 indicate low slipping potential, values between 25 and 34 suggest moderate risk, and values below 24 show high slipping potential.
• Texture was assessed using a portable laser profilometer mounted on a straightedge. At each location, sixteen profiles were measured (300 mm long and spaced 20 mm apart), covering a 30 cm² area. The Estimated Texture Depth (ETD), calculated from the mean profile depth, reflects the pavement’s capacity to drain water and affect walking comfort. ETD values below 0.7 mm may increase slipping risk due to smoother surfaces, while values above 1.2 mm improve drainage but may reduce comfort, particularly for wheelchair users.
• Heat retention was analyzed by recording surface temperatures using an infrared thermometer. Five readings were taken per point, and the average was used to characterize the surface’s thermal behavior. High surface-air temperature gradients (ΔT) indicate increased heat retention, negatively affecting pedestrian thermal comfort in sunny conditions.
• Maintenance condition was evaluated through systematic visual inspection of the pavement surface, identifying signs of deterioration, such as cracking, material loss, patching, or deformation. Although not instrument-based, this approach offers an objective, field-based perspective of maintenance quality across different segments.

The quantitative fieldwork was conducted on 5 and 6 April 2023, during the afternoon, under sunny, dry, and calm wind conditions. According to meteorological data for Braga, air temperatures ranged from 3.6 °C to 25.0 °C on 5 April and from 4.2 °C to 27.8 °C on 6 April.

2.5. Data Analysis

The qualitative data collected were analyzed using descriptive and inferential statistical methods. Descriptive statistics summarized participant demographic characteristics and the survey response distribution, including frequencies, percentages, means, and standard deviations (SDs).

Although pilot studies often rely on descriptive statistics [48], the sample size in this study allowed for statistical hypothesis testing that provided additional insights into the collected data. Chi-squared tests were used to analyze relationships between participants’ sidewalk material preferences and demographic variables (e.g., age and gender). The statistically significant differences identified in pedestrian material preferences by age and gender provide valuable insights for optimizing sidewalk infrastructure design.

3. Results

3.1. Subjective Evaluation (Qualitative Data Collection)

3.1.1. Sample Description

According to the 2021 Census, approximately 127,000 inhabitants reside within the urban boundary defined by the municipality [49,50]. In this pilot study, 70 individuals participated in the questionnaire. This sample size falls within the range established for pilot studies [51], ensuring a 75% confidence level with a margin of error of approximately 10%, which is acceptable for exploratory studies [48].

Table 2. Demographic characteristics and walking habits of the survey participants.

Variables	Attributes	Total	Percentage
Gender	Female	47	67.1
	Male	23	32.9
Age	≥18–≤24	15	21.4
	≥25–≤64	41	58.6
	≥65	14	20.0
Disability	No	67	95.7
	Yes	3	4.3
Origin	Resident	51	72.9
	Commuter	7	10.0
	Visitor	12	17.1
Walking habits	Daily/regular	57	81.4
	Occasional	13	18.6
Walking purposes (regular walkers)	Utilitarian	41	86.0
	Recreational/multiple reasons	16	14.0
Barriers to walk (occasional walkers)	Distance	6	46.1
	Time	3	23.1
	Others	4	30.8

presents the demographic breakdown. Most respondents were women (67.1%), aged between 25 and 64 years (58.6%), residing in Braga (72.9%), and without disabilities (95.7%).

A significant portion of participants (81.4%) reported walking daily or frequently (over three days per week) to meet their routine needs. In contrast, 18.6% walked only occasionally, opting for other modes of transport. This high proportion of regular walkers familiar with the city’s sidewalk materials and conditions along the selected route strengthens the reliability of their insights.

Regarding walking purposes, 86% of regular walkers cited utilitarian reasons, such as commuting to work, school, university, or accessing public transport. The remaining 14% walked for recreational purposes, including exercise or engaging in multiple activities, like shopping, accessing services, and leisure.

Among occasional walkers, 46.1% cited distance as the primary barrier, followed by time constraints (23.1%). Other constraints included participants’ physical limitations and inadequate pedestrian infrastructure, though only two respondents explicitly identified these as reasons for avoiding regular walking.

These findings provide an essential context for understanding the role of pedestrian habits and constraints in evaluating sidewalk conditions and material preferences.

3.1.2. Preferred Sidewalk Paving Materials

Regarding preferred sidewalk paving materials, participants could select up to two options. This possibility resulted in 104 responses from 70 participants (

Table 3. Participants preferred sidewalk paving materials and key influencing factors.

Pavement Attributes	CBs	M	PP	SSs	GBs	CTs	B
Total (N = 70)	31.7%	19.2%	10.6%	7.7%	1.9%	15.4%	13.5%
Roughness	34.4%	57.9%	44.4%	12.5%	0.0%	60.0%	53.8%
Friction	46.8%	36.8%	11.2%	50.0%	0.0%	26.7%	38.5%
Aesthetic	9.4%	0.0%	44.4%	12.5%	0.0%	13.3%	7.7%
Durability	9.4%	0.0%	0.0%	25.0%	0.0%	0.0%	0.0%
Drainage	0.0%	5.3%	0.0%	0.0%	100.0%	0.0%	0.0%

Legend: CBs = concrete blocks; M = mortar; PP = Portuguese pavement; SSs = stone slabs; GBs = granite blocks; CTs = ceramic tiles; B = bituminous.

). Concrete and mortar pavements were the most favored materials, followed by ceramic tiles and bituminous paving. Natural stone pavements, including the traditional Portuguese pavement, were less preferred.

Roughness and friction were the primary factors influencing participants’ material preferences. Concrete blocks were valued for their slip-resistant surfaces, while mortar surfaces were preferred for their smoothness and evenness. Participants favored ceramic tiles and bituminous materials for their regularity, with some also appreciating the aesthetic appeal of ceramic tiles. The attractive, smooth surface of Portuguese pavement and the durability and slip resistance of granite slabs—a traditional Braga building material—were appreciated features of natural stone sidewalks. In contrast, granite blocks were favored for their effectiveness in water drainage.

No participants explicitly considered heat retention when selecting paving materials, suggesting these attributes were not a primary concern.

3.1.3. Evaluation of Sidewalk Paving Attributes and General Characteristics

Table 4. Pedestrian evaluation (mean Likert scale ratings) of sidewalk paving and general characteristics.

Evaluated Attributes	Weighted Mean	Overall Mean	Standard Deviation
Sidewalk surfaces with adequate roughness	4.96	4.79	0.20
Sidewalk surfaces with adequate friction	4.91		0.37
Sidewalk surfaces with adequate texture	4.87		0.41
Sidewalk surfaces ensure thermal comfort	4.41		0.85
Well-maintained sidewalk surfaces	4.79		0.53
Wide sidewalks (>1.5 m)	4.60	4.64	0.74
Unobstructed sidewalks	4.87		0.44
Sidewalks with trees providing shade	4.60		0.73
Sidewalks with street furniture	4.36		0.97
Sidewalks with lowered ramps	4.77		0.56

presents participants’ evaluation of sidewalk attributes. All attributes were rated as being critical to walking, with mean values exceeding 4.0 on a 5-point Likert scale.

Paving-material attributes (mean = 4.79) were rated higher than general sidewalk characteristics (mean = 4.64), with roughness (4.96) and friction (4.91) being the most valued factors. The results underscore the necessity of incorporating pavement attributes more thoroughly into walkability assessments. Within the broader sidewalk characteristics, unobstructed sidewalks (4.87) received the highest rating, highlighting the importance of clear, obstacle-free pedestrian pathways.

Conversely, attributes such as tree-shaded sidewalks (4.60) and street furniture (4.36) were rated slightly lower, suggesting that participants prioritized functional pavement qualities over secondary environmental features.

Table 5. Mean ratings of sidewalk paving and general attributes by gender and age group.

Paving and Sidewalk Parameters	Gender		Age
	Female	Male	≥18–≤24	≥25–≤64	≥65
Roughness	5.00	4.87	4.87	4.98	5.00
Friction	4.98	4.78	4.93	4.93	4.86
Texture	4.98	4.65	4.93	4.90	4.71
Heat retention	4.55	4.13	4.40	4.49	4.21
Maintenance	4.89	4.56	4.80	4.76	4.86
Paving attributes’ overall mean	4.88	4.60	4.79	4.81	4.73
Wide sidewalks	4.74	4.30	4.27	4.58	5.00
Unobstructed sidewalks	4.91	4.78	4.80	4.85	5.00
Sidewalks with trees	4.68	4.43	4.27	4.68	4.71
Sidewalks with street furniture	4.57	3.91	4.33	4.22	4.79
Sidewalks with lowered ramps	4.91	4.48	4.87	4.71	4.86
General characteristics’ overall mean	4.76	4.38	4.51	4.61	4.87

highlights notable gender and age differences in pedestrian perception. Women consistently rated sidewalk quality higher than men, with the most significant difference observed for street furniture ratings (3.91 for males vs. 4.57 for females). This result suggests that female participants may be more attuned to elements that enhance pedestrian comfort and safety, such as smoothness, friction, and furniture, potentially due to differences in walking habits and urban mobility concerns.

Older participants (≥65 years) prioritized roughness (i.e., even surfaces), while younger individuals preferred smoother surfaces with sufficient grip, emphasizing friction. Unlike younger respondents, seniors placed greater importance on wide and unobstructed sidewalks (rated 5.0), likely due to accessibility concerns.

Older participants emphasized general sidewalk characteristics over paving attributes, highlighting the importance of spatial considerations in their walking experience. Except for seniors, adults generally rated paving attributes higher than general sidewalk characteristics, regardless of gender and age. Younger participants appeared less concerned with environmental features like trees and street furniture, indicating a stronger focus on the walking surface rather than surrounding amenities.

3.1.4. Evaluation of Sidewalk Paving Characteristics at Surveyed Locations

Table 6. Participants’ evaluation of paving materials at different locations along the route.

Street	Paving Material	n	Mean Score
Gabriel Pereira Castro, Conselheiro Januário, Nova de Santa Cruz, and D. Pedro V Sts.	Stone slabs	22	2.81
Nova de Santa Cruz St.	Concrete hexagons	21	3.28
Conselheiro Januário, and Taxa Sts.	Mortar	15	2.87
Conselheiro Januário, and Taxa Sts.	Portuguese pavement	10	3.20
Galiza Sq.	Granite blocks	2	5.00

presents participants’ evaluations of sidewalk paving conditions at various locations along the study route, using a 5-point Likert scale. Concrete hexagons, mortar, Portuguese pavement, stone slabs, and granite blocks were among the different paving materials observed at the selected sites.

Concrete hexagons, recently installed on Nova de Santa Cruz St., received the highest mean rating (3.28). In contrast, stone slabs and mortar pavements scored below 3.0 at other locations, while Portuguese pavement received a moderate score of 3.20. These findings suggest a preference for newer, well-maintained materials over older, uneven, or deteriorated paving types that may reduce comfort and create trip hazards.

The overall mean score of 3.09 indicates moderate satisfaction with sidewalk paving conditions along the route. The most frequently cited issue among participants who assigned ratings below 2.0 was excessive roughness (n = 22), particularly on older stone slab sidewalks that have become uneven over time, increasing trip hazards (e.g., D. Pedro V and Gabriel Pereira Castro Streets). Poor friction was the second most reported concern (n = 13), especially for Portuguese pavement, with three participants explicitly mentioning its slipperiness in wet conditions.

Twelve respondents noted inadequate surface maintenance across various materials, citing issues such as holes, cracks, and broken mortar (Conselheiro Januário and Taxa streets); cracked and uneven concrete block surfaces due to tree roots (Conselheiro Bento Miguel St.); or uneven stone slabs (D. Pedro V St.).

A smaller number of participants (n = 12) complained about thermal comfort, but they associated this problem with the lack of tree shading (e.g., Taxa St.) rather than the heat-retention properties of the paving materials themselves. Lastly, four participants reported problems with mortar surfaces related to inadequate drainage, leading to wet and slippery conditions.

These findings highlight the need for Braga’s urban planners to prioritize pedestrian-friendly paving materials and implement consistent maintenance strategies for enhancing pedestrian safety and comfort along the studied route.

3.1.5. Correlations Between Preferred Paving Materials and Demographic Variables

Table 7. Relationship between paving-material preferences and demographic characteristics (Chi-squared test results).

Variables	CBs	M	PP	SSs	GBs	CTs	B
Female (n = 75)	30.6%	22.7%	8.0%	8.0%	2.7%	13.3%	14.7%
Male (n = 29)	34.5%	10.3%	17.2%	6.9%	0.0%	17.2%	13.8%
Chi-squared	0.141	2.044	1.889	0.036	-	0.259	0.013
p-value	0.708	0.153	0.169	0.850	-	0.611	0.909
≥18–≤24 (n = 24)	29.1%	25.0%	4.2%	4.2%	4.2%	25.0%	8.3%
≥25–≤64 (n = 62)	40.3%	16.1%	6.5%	8.1%	0.0%	11.3%	17.7%
≥65 (n = 18)	5.6%	22.2%	33.3%	11.1%	5.6%	0.0%	22.2%
Chi-squared	7.550	1.257	11.989	5.691	-	-	1.670
p-value	0.022 *	0.533	0.002 *	0.058	-	-	0.433

Legend: CBs = concrete blocks; M = mortar; PP = Portuguese pavement; SSs = stone slabs; GBs = granite blocks; CTs = ceramic tiles; B = bituminous. * p-value < 0.05 shows statistical significance.

presents the correlations between preferred paving materials and demographic variables, highlighting notable differences in gender and age groups. The Chi-squared test results indicate that some preferences varied across demographic groups, but only specific differences reached statistical significance.

Women preferred smoother materials, such as mortar and bituminous mixtures, while men favored textured materials, including Portuguese pavement, ceramic tiles, and concrete. However, these differences were not statistically significant across all materials, as indicated by p-values above 0.05.

Age was a stronger determinant of paving-material preferences. The preference for concrete was significantly higher among adults aged 25–64 (p-value = 0.022), whereas older participants (≥65 years) showed a stronger inclination toward traditional materials, such as Portuguese pavement, stone slabs, and granite blocks. The significant preference for Portuguese pavement among seniors (p-value = 0.002) suggests that cultural and aesthetic considerations play a role in material selection.

These results underscore the importance of considering gender- and age-based preferences in the design of pedestrian infrastructure, including both practical and aesthetic factors, to reinforce pedestrian safety and comfort.

3.2. Objective Evaluation (Quantitative Data Collection) of Sidewalk Surface Attributes

This section presents the objective evaluation of sidewalks at the seven testing points along the pedestrian route, as described in Section 2.4. The physical performance of the sidewalk surfaces was assessed based on five attributes: roughness, friction, texture, heat retention, and maintenance condition. The values obtained are summarized in

Table 8. Quantitative evaluation results of sidewalk surface attributes at the seven testing points.

Testing Point	Material	Roughness (mm/m)	Friction (BPT Value)	Texture Depth ETD (mm)	Surface Temp. (°C)	Maintenance (Visual)
P1	Granite blocks	3.63	51	2.43	32.0	Good
P2	Stone slabs	3.29	30	1.30	40.5	Moderate
P3	Portuguese pavement	2.30	28	2.37	32.1	Good
P4	Mortar (well maintained)	1.39	49	1.49	40.0	Very good
P5	Mortar (deteriorated)	1.71	53	0.89	38.4	Poor
P6	Concrete blocks	3.13	60	0.84	42.6	Very good
P7	Concrete hexagons	2.22	52	1.39	43.5	Very good

.

Regarding surface roughness, mortar pavements—particularly the well-maintained surface at P4—exhibited the lowest values, indicating the most regular conditions with deformations below 1.7 mm. In contrast, pavements composed of individual units, such as granite blocks (P1), stone slabs (P2), and concrete blocks (P6), showed higher roughness values, with deviations exceeding 3.6 mm at P1. These results confirm that continuous surfaces like mortar are generally more even than modular pavements.

The friction results showed that concrete, mortar, and granite surfaces presented high BPT values (>50), suggesting low slip potential under wet conditions. Conversely, Portuguese pavement (P3) and stone slabs (P2) showed moderate slip risk, with BPT values of 28 and 30, respectively. These materials are characterized by smoother, polished finishes that increase the likelihood of slipping, especially in rainy weather.

Regarding texture, granite blocks (P1) and Portuguese pavement (P3) recorded the highest ETD values, near 2.4 mm, which enhance traction and water drainage. However, excessive jointing or uneven blocks may cause discomfort for wheelchair users. The smoothest textures were observed at P5 and P6, with ETD values below 0.9 mm, indicating more uniform surfaces.

The heat-retention analysis revealed that the highest surface temperatures (>42 °C) occurred on concrete pavements at P6 and P7. With darker tones, these materials absorb more solar radiation, leading to more significant thermal buildup. In contrast, granite blocks (P1) and Portuguese pavement (P3), with lighter tones and higher reflectivity, exhibited lower temperatures (around 32 °C). The temperature differential between materials reached 11.5 °C, highlighting the impact of surface type on thermal comfort. Notably, all surface temperatures exceeded the maximum recorded air temperature, with differences ranging from +4 °C (P1, P3) to +15.7 °C (P7).

Finally, maintenance conditions were assessed through visual inspection. Well-maintained surfaces—such as concrete (P6, P7) and mortar (P4)—showed no visible defects, receiving a “very good” classification. Deteriorated mortar (P5) displayed surface wear, cracks, and patching, while stone slabs (P2) were categorized as “moderate” due to joint degradation and aging signs. This field-based observation reinforces the relevance of surface maintenance, as visually deteriorated areas were frequently associated with lower performance across other measured attributes.

4. Discussion

This section presents a comprehensive discussion of the findings, exploring the relationship between pedestrian preferences and objective paving evaluations, the influence of demographic factors, weather conditions, and the variability of sidewalk conditions along the route.

4.1. Pedestrian Paving Preferences vs. Objective Surface Evaluations

In this pilot, most participants (51%) preferred concrete and mortar pavements for their slip resistance, smoothness, and surface regularity, contributing to enhanced pedestrian safety and comfort. These perceptions align with several measurements taken along the route (Table 8). The friction test results reveal that sidewalks paved with concrete blocks and mortar had low slip potential, with BPT values significantly above 35—the minimum required for adequate slip resistance [20,52]. Concrete, often described as the “stone of the 20th century” [37], has become widely used in outdoor infrastructure due to its reliable microtexture, generally outperforming natural stone pavements in terms of safety [53].

Natural stone pavements were less preferred by participants, suggesting that these materials contribute less to pedestrian safety and comfort. The lowest evaluations from participants were associated with stone slabs. Surface roughness tests confirmed that sidewalks paved with granite blocks and stone slabs were the most irregular, with deviations exceeding 6 mm, which may pose tripping hazards [54]. These results are consistent with previous research showing that pavements constructed from individual units tend to become uneven over time due to improper installation, tree root growth, unauthorized vehicle traffic, and water infiltration [12,55]. Such surfaces may also cause discomfort for wheelchair users due to increased vibrations and noise [20]. Accordingly, only 12.5% of pedestrians identified stone slabs as preferable regarding roughness, confirming an overall accurate perception of their lower regularity. Similarly, granite blocks were positively mentioned for their drainage properties—a perception supported by the high ETD values for this material, likely resulting from the multiple joints typical of small-block paving.

However, some mismatches were also observed between subjective evaluations and measured performance. For instance, 50% of participants preferred stone slabs, and 11% selected Portuguese pavement based on perceived friction. However, friction tests conducted at P2 and P3 revealed that these two materials performed the worst, with BPT values below 35, showing a moderate slipping potential. These pavements have smooth, polished surfaces that tend to degrade over time, increasing the risk of slipping, especially under wet conditions [52]. Portuguese pavement has long been debated in Portugal because of its known slipperiness, posing particular risks to older adults and tourists unfamiliar with its surface behavior.

In summary, the quantitative evaluation confirmed pedestrian perceptions, particularly regarding the roughness and drainage of certain materials. However, some discrepancies persist, suggesting individuals may have varying perceptions of specific material attributes, especially regarding friction.

4.2. The Influence of Demographics on Paving Preferences

The observed variations in paving-material preferences across demographic groups in this pilot may be influenced by comfort perception, safety concerns, and cultural familiarity. Gender-based differences suggest that women prioritize smoother surfaces, possibly due to greater sensitivity to trip hazards or differences in footwear. Women consistently rated all paving and sidewalk attributes higher than men, indicating that gender may influence how surface characteristics—such as smoothness or slipperiness—are perceived concerning safety and comfort. This finding aligns with previous studies showing that women are more concerned with pedestrian safety [56,57] and sensitive to infrastructure conditions [56,58,59]. It may also reflect that women, on average, walk more frequently than men [57] and are statistically more likely to be involved in pedestrian falls [17,23]. These factors could help explain the stronger preference among women for mortar pavements, which offer regular, stable, and slip-resistant walking surfaces.

Age-related differences in perception were also evident. Among older participants, roughness was considered the most important attribute, which supports findings from previous research linking uneven surfaces to a higher risk of falls and fear of falling among older adults [60]. Interestingly, seniors often preferred Portuguese pavement, which, according to the objective surface scores presented in Table 8, is neither the most regular nor safest regarding friction. Portuguese pavement’s cultural value and urban identity may explain this apparent contradiction. For many older individuals, these surfaces represent a heritage element deeply embedded in collective memory [61], and familiarity with the material may enhance comfort or acceptance. There is evidence that familiar urban environments positively influence the age-friendliness of cities [62].

In contrast, younger and working-age adults prioritized paving attributes more than broader sidewalk features. Unlike seniors, they were more likely to favor concrete pavements, which offer functional benefits, such as uniformity and slip resistance. These preferences may reflect a more utilitarian approach to walking infrastructure, especially among individuals with limited time and higher mobility needs [63].

From this pilot study, it can be concluded that designing sidewalks that consider gender- and age-based preferences can help create more inclusive, walkable urban environments. Ensuring that surfaces are well maintained and responsive to the needs of diverse pedestrian groups ultimately contributes to a safer and more comfortable public realm for all.

4.3. The Influence of Weather Conditions

Weather conditions are a well-recognized factor influencing travel behavior. Adverse weather, in particular, is a barrier to walking, making pedestrian trips uncomfortable and unpleasant [56,64]. In addition, evidence suggests that most pedestrian falls occur on wet and icy surfaces due to reduced surface friction, with falls being more frequent during the winter [17,21,23].

Winters in Braga are not cold enough to create icy or snow-covered sidewalk surfaces. However, precipitation is most concentrated in the autumn and winter months. Since both the qualitative (survey) and complementary quantitative evaluations were conducted during spring, the full effects of wet and cold weather may not have been fully captured—especially in pedestrian perceptions. Nonetheless, as shown in Table 1, the survey period covered various meteorological conditions. Rain was recorded on 21 days, with the second week of June (7–14 June) being the wettest, accumulating 156 mm/m² of precipitation. Notably, the friction tests were conducted on wet surfaces, with water manually applied before each test, ensuring a realistic evaluation of slip potential.

The analysis period also encompassed significant thermal variation, with maximum air temperatures ranging from 19.9 °C (30 May) to 31.0 °C (7 June). Solar radiation levels exceeded 1000 W/m² on 86% of the days, indicating predominantly sunny or partly cloudy conditions. Although these values may not fully reflect the specific microclimatic conditions at the sidewalk level throughout the year, they provide a reasonable context for evaluating thermal behavior, as reflected in the heat-retention data presented in Table 8.

In conclusion, although the evaluations captured various weather conditions, they may not fully reflect seasonal extremes. Future research should aim to expand data collection across different seasons, particularly during winter and under naturally wet conditions. That development would offer a more comprehensive understanding of how weather interacts with sidewalk materials to influence pedestrian safety and comfort.

4.4. Variability in Sidewalk Conditions Along the Route

The study conducted in Braga revealed significant variability in pavement materials and conditions along the selected pedestrian route, highlighting a lack of standardization in both material selection and surface conditions across different streets that directly affects pedestrian safety and comfort. This result is consistent with previous studies showing diverse paving-material mixes in sidewalk construction [61]. The route included recently installed concrete sidewalks (e.g., Nova de Santa Cruz St.), which were in good condition, and older sidewalks paved with uneven and polished granite slabs (e.g., D. Pedro V St.). However, it also includes sections paved with materials in poor condition, showing broken surfaces and holes (e.g., Conselheiro Januário and Conselheiro Bento Miguel Sts.). Thus, the selected route does not always meet established design guidelines, which require sidewalk surfaces to be uniform, slip-resistant, firm, and free from physical irregularities to ensure adequate mobility and accessibility for all pedestrians [12,65,66].

The moderate satisfaction score (3.09) for paving conditions suggests that participants were aware of these sidewalk conditions and their impact on walkability. Specific issues identified include the following:

• Uneven surfaces on stone slab pavements, posing trip hazards.
• Insufficient friction on Portuguese pavement, increasing the risk of slips.
• Poor maintenance evidenced by cracked surfaces, potholes, uneven blocks, and deteriorated mortar pavements along the route.
• Reduced thermal comfort, particularly in areas with insufficient tree cover.

These findings highlight the need for targeted interventions to improve sidewalk quality, aligning them with best practices and safety regulations. Standardizing materials and implementing consistent maintenance strategies based on subjective assessments and the quantitative evaluation of paving attributes can help create a safer and more comfortable pedestrian environment for all users.

5. Conclusions

Pedestrian infrastructure, particularly sidewalks, is crucial for safe and comfortable walking experiences. The quality of sidewalk surfaces, including the materials used and their maintenance, significantly impacts pedestrian safety and comfort. However, paving attributes have been largely overlooked in pedestrian studies, often leading to potential overestimations of walkability [25,67]. This pilot study contributes to bridging this gap by evaluating the role of paving attributes in shaping pedestrian experiences, thus expanding the limited literature on this topic.

Understanding how pedestrians perceive different materials can help city authorities make informed decisions for sidewalk design, contributing to safer and more comfortable urban spaces. Based on the insights gathered from a questionnaire conducted in Braga, Portugal, this pilot confirms that sidewalk paving attributes are perceived as key determinants of walkability. Participants rated these attributes higher than broader sidewalk characteristics usually included in walkability evaluations, like width or street furniture.

In terms of practical planning recommendations, this pilot suggests that well-maintained concrete and mortar surfaces should be prioritized in future sidewalk designs. Concrete pavements were preferred for their slip-resistant performance, while mortar surfaces were valued for their smoothness and evenness—an outcome confirmed by the complementary quantitative evaluation. Maintenance and repair actions to prevent these surfaces from becoming uneven (e.g., due to tree rooting) are essential to enhance pedestrian safety and comfort. Other materials, such as stone slabs, can be optimized through proper installation and consistent maintenance, while the slipperiness typical of some surfaces—such as Portuguese pavement—can be mitigated by surface texturing or applying anti-slip treatments. In addition, integrating deciduous street trees can help reduce heat retention in high-temperature conditions and improve winter comfort.

The comparison between pedestrian preferences and engineering-based evaluations in this study offers a practical framework for identifying mismatches between perceived and actual material performance. Given the importance assigned by participants to sidewalk paving, these attributes should be more systematically included in walkability studies. One of the main barriers is the lack of comprehensive sidewalk data, particularly regarding surface characteristics. Future research should address this gap by integrating advanced data collection techniques, such as mobile sensors and AI-driven sidewalk mapping. Additionally, crowdsourced data and standardized walkability audits can support better-informed infrastructure planning by incorporating real-world insights into material selection and maintenance strategies.

While based on a limited sample (N = 70), this pilot provides valuable insight into how pedestrians perceive different paving materials and offers a foundation for further investigations. Nevertheless, some limitations must be acknowledged due to the study’s exploratory nature. First, expanding the sample size and achieving a more balanced demographic distribution would enhance the generalizability of the results. Second, assessing seasonal weather variation over a year would improve understanding of its effects on sidewalk performance and pedestrian perceptions of safety and comfort. Third, evaluating paving materials that were not present in the study area, such as ceramic tiles, would broaden the scope of the analysis. Finally, incorporating an objective performance assessment of sidewalk attributes, as demonstrated in this study, proved helpful in reinforcing the interpretation of pedestrian perceptions and should be extended in future research. Despite these limitations, this pilot study highlights the value of combining subjective and objective evaluations to support more inclusive, data-informed decisions in pedestrian infrastructure design.