Current Construction Practices Research Articles

Development of superpave asphalt binder specifications to meet climate conditions in the UAE

ABSTRACT Asphalt binder's performance is highly sensitive to temperature fluctuations and climatic conditions. The selection of an inappropriate asphalt binder leads to considerable damage and impacts roads' longevity. The current selection practice of asphalt binder in the United Arab Emirates (UAE) is mainly according to the penetration grading system, which does not consider local temperature conditions. The Superpave Performance Grade (PG) system considers extreme pavement temperatures to define appropriate asphalt binder PG. This study aimed at developing the Superpave asphalt binder PG map for the UAE. The Strategic Highway Research Program (SHRP) and Long-Term Pavement Performance Program (LTPP) Superpave models were used to calculate the pavement temperatures employing air temperature records collected from 20 weather stations across the UAE. The result of the Superpave PG map highlights three distinct asphalt binder grades at 98% reliability: PG 76-10, PG 70-10, and PG 64-10. The PG 76 -10 asphalt binder is the most prevalent PG, covering more than 85% of the UAE map. However, the current construction practice utilizes penetration grades 40/50 and 60/70, through both asphalt binders are equivalent to PG 64-xx. This necessitates the use of different modifier technologies to achieve the Superpave requirements of PG 76-10 and PG 70-10.

Feasibility of sliding base isolation for rubble stone masonry buildings in the Himalayan Mountain range

This paper studied the feasibility of a sliding base isolation layer to be used in rubble stone masonry buildings in rural areas in the Himalayan Mountain range to provide robust protection to important building like schools against strong earthquakes. In this paper, we carried out on-site investigations, quasi-static tests, and shaking table tests focusing on constructability as well as isolation performance. From the results of the feasibility study, the combination of styrofoam, concrete slab, and grease was found to be the most feasible to be used as the upper element, the lower element, and the lubricant, respectively, in the sliding isolation layer. The key features of the present sliding base isolation layer are: 1) the use of the materials that exist in rural mountain areas or those that can be easily transported from the neighboring towns and cities and 2) ease of construction and minimal change from the current construction practice. From the shaking table tests, we identified the conditions, e.g., grease amount, grease type, normal stress at the interface, and roughness of concrete slab surface, to achieve dynamic friction coefficients ranging from 0.08 to 0.16, suitable for sliding base isolation.

A Future Growth Model for Building More Housing and Infrastructure with Less Embodied Greenhouse Gas.

Global demand for housing and the climate crisis have created a seemingly impossible choice between the need to build more and the need to emit less from construction materials. Here, we present the future infrastructure growth (FIG) model, a generalizable method for finding pathways to build enough housing and infrastructure while reducing material emissions, in line with climate commitments. FIG uses open data to quantify the emissions of existing neighborhoods as if they were built new; it then uses these quantifications to forecast future cradle-to-gate embodied emissions from new residential buildings and linear infrastructure construction. This novel approach allows for detailed analysis that scales to a city, region, and/or national level and captures variability in construction norms, designs, and codes. We demonstrate FIG on Canada, using the model to find neighborhood-level drivers of embodied emissions and the most effective reduction strategies through 2030 and 2050. Current construction practices will cause a 437% overshoot of Canada's climate commitments if housing growth targets are met. Avoiding this overshoot requires a near-total reliance on multiunit buildings and best-in-class design supported by improvements in material manufacturing, building within existing urban boundaries, and halving the use of new materials.

Mapping construction sector greenhouse gas emissions: a crucial step in sustainably meeting increasing housing demands

This paper examines the tension between needing to build more infrastructure and housing and simultaneously reduce greenhouse gas emissions (GHG) to avoid the most catastrophic impacts of climate change. This study uses an Environmentally Extended Input-Output approach to conduct a high-resolution top-down analysis of Canada’s national construction GHG emissions. Our findings highlight that Canada’s current construction practices cannot accommodate the construction required to restore housing affordability by 2030 without substantial environmental consequences. On a consumption life cycle basis, the construction sector was responsible for approximately 90 Mt CO2e in 2018, equivalent to over 8% of Canada’s total GHG emissions, while delivering less than a third of Canada’s annual housing needs. Residential construction was responsible for the largest share (42%) of total construction emissions. Overall, 84% of emissions are from material manufacturing and 35% of construction emissions are imported, underscoring the need for a comprehensive regulatory framework addressing both domestic and imported emissions. Under current construction practices (i.e. current material use patterns and emissions intensities), meeting Canada’s 2030 housing affordability and climate commitments requires an 83% reduction in GHG emissions per construction product (i.e. per home) compared to the 40% economy-wide reduction promised in Canada’s international reduction commitments. Mitigating the GHG gap between emission caps and housing demand calls for changes in the ratio of housing to other infrastructure (e.g. fewer roads, less fossil fuel infrastructure), new construction approaches (e.g. increasing material efficiency) and/or disproportionally allocating climate budget to construction. The implications of our study extend beyond Canada, offering valuable insights for other growing countries with climate goals. The results emphasize the urgency in considering and establishing sectoral GHG budgets for construction and for transformative changes in the construction sector to meet national GHG emission reduction commitments.

Spectral optical performance of phase-change-material-filled glass-block system: Experimental evaluation and comparative exploration

Research on sustainable building design is pushing boundaries to introduce innovative solutions that enhance energy efficiency and improve user comfort. The integration of phase-change materials (PCMs) into transparent façade elements has gained substantial attention; however, its widespread application in current construction practices remains limited. This study examined the solar/light transmittance of PCM-based materials embedded in transparent façade elements, focusing on providing and comparing the optical properties of modular glass blocks integrated with PCM measured experimentally in a laboratory setting. Optical properties of multi-layer and non-homogeneous systems represent a more complex problem in terms of proper characterisation. To overcome this limitation, more comprehensive approaches can be considered, including integrating spheres to perform measurements on the complex nonhomogeneous glass system. This study employed spectrophotometric measurements within the visible and near-infrared (NIR) spectra by two different measurements methods: a direct method and one using an integrating sphere. Additionally, the investigation was based on a comparison between clear and various PCM-filled glass blocks. The results demonstrated that the direct method facilitated reliable spectral transmittance measurements with deviations not exceeding 3 %. In addition, the results revealed that paraffinic PCM glass blocks in liquid phases could achieve up to 90 % of light transmission and act as a highly transparent system in the visible region compared with conventional air-based glass blocks (up to 77 %). However, in the NIR region, the spectral transmission of PCM glass blocks was reduced by half (around 46 %). Depending on the PCM type in solid phases, the visible transmission is significantly reduced, which is from 5 % to a maximum of 19 %. This study contributes to the expanding knowledge base on adaptive building systems, particularly those related to PCM integration in transparent façade components.

New and Sustainable Coal Char-Based Paving Blocks for Roadway Applications

Paving blocks are widely used in engineering construction for durable pavement surfaces characterized by their interlocking capability to enhance structural integrity. This study explores the potential use of char as a byproduct from coal pyrolysis and an alternative raw material to natural aggregates in developing paving blocks, aiming to reduce the associated environmental issues associated with the uncontrolled and excessive mining of natural resources. This study finds the paving blocks made from char to have the required engineering properties as mentioned by ASTM standard C936. Trass and trass-lime are added as supplementary cementitious materials (SCMs) to enhance the performance of char-based paving blocks. The incorporation of SCMs as a cement replacement also aims to reduce the carbon footprint arising from increased cement use. The compressive strength increased from 55.7 MPa to 65.71 MPa at 12.5% cement replacement with trass-lime. The water absorption is reduced to 4.63% from 4.95%. Beneficial effects towards freeze–thaw durability and abrasion resistance are also observed on trass-lime-incorporated paving blocks. This study signifies the remarkable potential use of coal-derived char and SCMs in developing light, high-strength, and durable paving blocks, showcasing their competitive engineering performance. These new char-based paving blocks will contribute towards a more sustainable construction environment and advance the current construction and engineering practices.

Research on Risk Prediction of New Energy Photovoltaic Power Projects Oriented to Extreme Weather Conditions

Abstract In light of the increasing frequency of extreme weather events—including persistent low temperatures, rain, snow, freezing conditions, and haze—globally, the vulnerability of photovoltaic (PV) power projects to severe weather has escalated. This study presents a comprehensive analysis of the current construction practices and associated risks of PV power projects. Subsequently, it introduces two innovative risk prediction models: the gray risk prediction model and the CEMD-LSTM risk prediction model, which is enhanced by an improved k-shape clustering algorithm. These models are specifically designed for assessing the risks of new energy PV power projects under extreme weather conditions. To validate the effectiveness of these models, simulation tests are conducted, offering insights into the risk dynamics of new energy PV power projects in adverse meteorological scenarios. The assessment results show that the absolute error of the prediction results of the gray prediction model is large. The absolute value of the absolute error reaches a maximum of 8.0×104 W. The fluctuation of the prediction value is huge, so it is not possible to accurately carry out the risk prediction. The values of MAPE and MSE of the CEMD-LSTM model are 3.26% and 0.21, respectively, and the rate of identification of the risk level of the CEMD-LSTM model is 98.25%, which is higher than 93.48% of the LSTM model. The CEMDLSTM model is capable of predicting the risk of PV power projects with accuracy, and the recognition accuracy of the risk level is superior to that of the LSTM model. This study provides lessons and references for risk prediction of PV power projects in extreme weather conditions.

Effect of masonry wall on Strength and Ductility in common RC frame low storey buildings

The Nepal National Building code (NBC) was promulgated in 2003 and is divided into four different parts in order to cover buildings constructed in Nepal. NBC 105 has undergone a major update in 2020 with its repercussions on existing prevalent buildings. So, in this paper effort has been made to understand municipal drawings submitted to municipalities constructed with current prevalent building construction practice with column size of 300mm x 300mm, 300mm x 230mm and 230mm x 230mm. Moreover, effects of masonry infill are considered with a separate model considering an equivalent strut as per IS 1893:2016. Ten sample buildings were selected after a rigorous sampling process of over 5000 municipal drawings to represent typical buildings. Non-linear static pushover analysis was conducted on those ten buildings and twenty models. There has been an increase in the over-strength factor of the buildings while there was reduction in ductility factor of the buildings. Equations are proposed based on non-linear regression analysis to determine the changes in over-strength and ductility factor of the buildings.

Boundary Integrity Testing of Containment Level 3 (Biological Safety Level 3) Laboratories.

Containment Level 3 (CL3) laboratories may require boundary integrity testing. Existing guidelines for CL3 room leakage are often subjective, lacking a definitive standard for what constitutes a "sealed" room. This study reviews global biocontainment guidelines and standards, and it compares multiple test results from global CL3 facilities by standardizing test data to an equivalent test pressure of 250 Pa. Our analysis revealed that 55% of rooms constructed using typical CL3 methodologies met the proposed testing criteria. The United States Department of Agriculture (USDA) Agricultural Research Service (ARS) greenhouse leakage rate acceptance criterion of 0.139 L/s per square meter (0.027 cfm per square foot) at a room differential pressure of 250 Pa was found to be a challenging, yet achievable standard. A two-step process is recommended for boundary integrity testing: (1) Initial leaks are identified using smoke pencil or soap bubble tests, followed by necessary repairs; (2) The room is then subjected to quantifiable leakage rate testing to verify it meets minimum requirements. In the absence of definitive local guidelines, we recommend the published ARS greenhouse leakage rate at a room differential pressure of 300 Pa of 0.152 L/s per square meter of surface area as an acceptable criterion for testing construction boundaries of CL3 laboratories built using current CL3 construction practices. For primary containment CL3 rooms, a more stringent criterion following the German Verein Deutscher Ingenieure guidelines at a room pressure differential of 250 Pa is noted as 0.03620 L/s per square meter of room surface area is more appropriate.

Assessment of the embodied carbon performance of post-tensioned voided concrete plates as a sustainable floor solution in multi-story buildings

With growing concerns for the building industry’s contribution to climate change, designers are considering the global warming potential and corresponding embodied carbon (EC) emissions of building structures. However, conventional reinforced concrete (RC) floors are one of the highest contributors to the EC in a multi-story building. A solution to reduce EC that combines proven construction technologies is post-tensioned (PT) voided plates, where void formers are placed in areas where less material is required, therefore increasing the effectiveness of the pre-stressing, and reducing substantial structural material. This paper assesses the EC of PT voided plates for three different tendon layouts and compares them to RC flat plates, RC voided plates, and PT flat plates. 3280 different design conditions are assessed to replicate the range of common applications of each concrete floor system. The minimum required material quantities were determined for each design condition, which were used to calculate and compare the corresponding EC. The EC results for the floor systems were also compared to other sustainable floor designs. This paper found that PT voided plates have an EC savings up to 51 % compared to conventional floors and are a sustainable floor system that can be built worldwide using current construction practices.

Analytical Review of Key Barriers in Implementing Sustainable Construction

It has been demonstrated that sustainable building development has a distinct positive impact on the environment, and it has been identified as the current trend in environmental protection. Green building construction or sustainable construction can be influenced by various factors, including the type of buildings constructed, the type of materials employed, and the energy efficacy of their operation. The Green Building Index (GBI) which have been introduced and implemented in Malaysia is a rating system that seeks to promote the use of energy-efficient buildings. This is in line with the Sustainable Development Goals (SDG) and the Twelfth Malaysia Plan (2021-2025), where it is focusing on green growth for sustainability and resilience communities. Sustainable constructions benefitted the construction industry in terms of environmental, social, and economical benefits. However, various benefits and drawbacks are luring and discouraging industry practitioners from implementing sustainable construction in their projects. Therefore, this paper aims to identify the key barriers in implementing sustainable construction in Malaysia. The literature findings reveal that there are generally 9 barriers towards the implementation of sustainable construction. Out of these, five are identified as the most critical barriers in the best practice of sustainable construction towards implementing the sustainable construction in the country. The findings can serve as added value to existing practice, which has previously been more concerned with design and benefit consideration. Therefore, it will also help to improve the current construction practice undertaken by industry practitioner.

Residual load capacity of HVFA reinforced concrete after elevated temperature heating: Experimental and analytical study

High volume fly ash (HVFA) is used as structural concrete's main constituent in the current concrete construction practice. The residual load capacity of HVFA reinforced concrete after elevated temperature heating is needed for retrofitting compression members after fire exposure. In this experimental study, an effort has been made to estimate the axial load capacity of concrete containing HVFA after 28 and 90 days of curing after elevated temperature heating at 200 °C, 400 °C and 600 °C. The 35% and 50% amount of cement was partially replaced by fly ash. The weight loss and crack pattern in reinforced HVFA concrete were also studied. It has been observed that after heating at elevated temperature, the compression behavior of fly ash concrete is better than that of plain concrete. The analytical models are proposed to estimate the residual load capacity of HVFA concrete columns after exposure to elevated temperature. The model predictions are reasonably good. These models can be used to assess the load carrying capacity of columns in concrete buildings containing HVFA after elevated temperature exposure for deciding strengthening schemes.

Numerical Investigation on the Performance of Exterior Beam–Column Joints Reinforced with Shape Memory Alloys

Upgraded design standards coupled with the damage caused by natural disasters have led to the development of smart materials with the potential to modernize current construction practices. This investigation proposes a nonlinear finite element (FE) model for evaluating the performance of beam–column joints (RC-BCJ) reinforced with shape memory alloys (SMA) and steel rebars. The model was validated based on accredited experimental data, followed by parametric analysis in ABAQUS to optimize the use of SMA bars for enhancing the seismic resistance of RC-BCJ without compromising their energy dissipation capacity. Parameters investigated include the (a) SMA–steel reinforcement ratio, (b) lengths of SMA bars, (c) elastic modulus of SMA, (d) compressive strength of concrete, and (e) axial load applied on the column. The finite element simulation results indicated that the model was capable of predicting the optimum length of SMA bars sufficient for relocating the plastic hinge away from the face of the column along the beam. Further, simulation results proved that the use of SMA bars in conjunction with steel reinforcement could be considered as an effective tool for enhancing the seismic performance of RC-BCJ joints. Among the parameters investigated, high-strength concrete was the most effective in improving joint resistance.

Definition of the most commonly used ceramic brick for construction in Ecuador: Type and dimensions

In Ecuador, 95.9% of housing is built with the use of masonry. Current construction practice in Ecuador shows that masonry is mainly used as enclosing or partition elements and they are not considered as part of the resistant structural system even though masonry walls can work as an active structural element and their work is defined by their geometry and the mechanical properties of the bricks, mortar and their contact interaction. The aim of this work is to characterise the type and geometry of the most commonly used ceramic brick for construction in Ecuador and the particularities of its production. For this propose, field data were collected in 48.9% of the Ecuadorian territory, where 79.19% of the country's population is concentrated and statistical data processing was performed. The results show that the production of bricks in Ecuador is mainly artisanal and 92% of the factories produce solid bricks. The research showed that there are no scientific works on the geometrical characterisation of bricks in Ecuador. The data analysis shows that there is a regional influence in the average brick dimensions, where bricks produced in the coastal region are 35 × 19 × 7 cm; in the central-northern Andes 28.0 × 11.0 × 9.0 cm; in the southern Andes 25.7 × 13.0 × 7. 5 cm with CVlength = 1.21%, CVwidth = 1.31%, CVheight = 3.07%; and, in the Amazon region 25.1 × 11.8 × 7.2 cm, with CVlength = 0.92%, CVwidth = 1.27 %, CVheight = 2.36%. An important identified fact is that only 4.8% of brick manufacturers in Ecuador comply with the national standard dimensions.

Out-of-plane analysis of dry-stone walls using a pseudo-static experimental and numerical approach in natural-scale specimens

On the slopes of some Andean cities, the population is at high seismic risk due to their informal homes, built without technical advice, based on non-compacted backfill, and supported by dry stone retaining walls (pircas). In this work, we aimed to evaluate the out-of-plane performance of the typical retaining walls of the city of Lima, Peru, located on the slopes of the central Andes. In this first study, the effect of the backfill has not been considered because only the behavior of the wall was studied. Three walls of height 1 m and three of height 1.5 m were built and tested. The construction was carried out by local workers, following their traditional practices, and tests were carried out on a tilting platform to generate out-of-plane gravity loads. Delamination and overturning were the most frequent types of failure. From the experimental tests, we found that the average ultimate resistance to displacement was 31 % and 24 % of the weight for the 1 m and 1.5 m walls, respectively. The discrete element method was used for the numerical models, and the contact parameters of stiffness and friction angle corresponding to the Coulomb model were calibrated using the experimental results. The effects on the mechanical behavior of the use of through stones and overlaps between wall elements were studied. It was concluded that the pircas could be improved to a limited extent with better construction practices, and further studies are therefore required with the aim of improving current construction practices. In a later study, the interaction between the wall and the backfill will be studied numerically and experimentally.

Overheating Risk Analysis in Long-Term Care Homes—Development of Overheating Limit Criteria

Climate heat waves occurring in urban centers are a serious threat to public health and wellbeing. Historically, most heat-related mortalities have arisen from excessive overheating of building interiors housing older occupants. This paper developed an approach that combines the results from building simulation and bioheat models to generate health-based limit criteria for overheating in long-term care homes (LTCHs) by which the body dehydration and core temperature of older residents are capped during overheating events. The models of the LTCHs were created for buildings representative of old and current construction practices for selected Canadian locations. The models were calibrated using measurements of indoor temperature and humidity acquired from monitoring the building interiors and the use of published building energy use intensity data. A general procedure to identify overheating events and quantify their attributes in terms of duration, intensity, and severity was developed and applied to LTCHs to generate the limit criteria. Comparing the limit criteria from the proposed and comfort-based methods showed evident differences. The proposed method predicted the overheating risk consistent with the overall thermal comfort during overheating events in contrast to the comfort-based methods. The new limit criteria are intended to be used in any study to evaluate overheating risk in similar buildings.

Construction and Performance Evaluation of Polyurethane-Bound Porous Rubber Pavement (PRP) Trial Section in the Cold Climate

Porous pavements are designed and used in current construction practices to address environmental and safety issues related to wet weather. Porous rubber pavement (PRP) is a novel porous pavement material consisting of recycled crumb tire rubbers, stone aggregates, and polyurethane binders. The higher permeability (up to 45% of air voids) of PRP and its composition offers excellent benefits to the urban hydrological system and environment. Due to its recent outset in the Canadian climate, its properties and performance are not yet investigated. This research investigates PRP’s properties and performance as pavement material through the construction of two trial sections incorporating three newly developed PRP mixes along with a Control Mix. Samples were obtained from the field and tested in the laboratory to determine the mechanical and durability properties, including indirect tensile strength, moisture-induced damage due to freeze-thaw cycles and permanent deformation. A field evaluation was also performed three times: right after construction, three weeks later and after seven months to determine stiffness, frictional properties, roughness and permeability. The results revealed that all PRP mixes exhibited excellent permeability and retained more than 68% of tensile strength after five freeze-thaw cycles. Although PRP showed significantly lower initial elastic modulus than conventional pavement material, ranging between 28 MPa to 59 MPa, in the springtime none of them went below 23 MPa. Material composition, site geometry and subgrade conditions were found to be the main factors influencing the field performance of PRP pavement.

Prefabricated thermally-activated fiber-polymer composite building slab P-TACS: Toward the multifunctional and pre-fabricated structural elements in buildings

The traditional sequential design of building elements, where every element performs only one dedicated function, carries significant embodied energy. Thus, modular pre-fabricated load-bearing elements could overcome the disadvantages of the current carbon-intensive construction practice and go beyond; as such, lightweight glass fiber-polymer composite profiles could be more advantageous in performance. Cellular structures of such profiles can be advantageous for adding water channels for active heating and cooling indoors and for fire protection. Therefore, the development of such a modular active building slab referred to as P-TACS (Prefabricated Thermally-Activated Fiber-Polymer Composite Slab) is explored in this work. The structural performance of a proposed P-TACS design is verified in terms of serviceability and ultimate limit states. The addition of local carbon fiber inclusions allows for an increase in the span of the slab to 10 m and a more uniform surface temperature. Thermal performance of the structurally optimized geometrical configuration is analyzed by, first of all, determining water parameters based on the 1D approach partially adopted from the standard radiant systems analysis and, secondly, by a detailed 2D thermal analysis using ANSYS Fluent numerical simulations. The hydraulic and thermal performance comparison of the novel P-TACS design with two standard radiant systems (ESS Type A and RCP) reveals that the P-TACS design outperforms the standard embedded surface system ESS Type A, both for floor heating and cooling case. In addition, the response time of P-TACS is three times faster compared to the ESS response time. The main advantage of the P-TACS is in lower mean water temperature, compared to traditional embedded radiant systems (e.g., EES type), required for conditioning the space, potentially resulting in lower operational energy use. The fire outbreak scenario is considered to complete the analysis, and the measures to switch water flow from nominal to fire scenario are proposed.

Extended Reality for Safe and Effective Construction Management: State-of-the-Art, Challenges, and Future Directions

Safe and effective construction management requires tools for reducing delays, eliminating reworks, and avoiding accidents. Unfortunately, challenges still exist in current construction practices for enabling real-time interactions among project participants, field discoveries, and massive data. Extended reality (i.e., XR) could help to establish immersive and interactive virtual environments that enable real-time information exchange among humans, cyber processes, and physical environments during construction. However, limited studies have synthesized potentials, challenges, and scenarios of XR for ensuring construction safety and efficiency. This study provides a critical review that synthesizes XR in construction management. First, the authors used the PRISMA method to screen studies related to XR in construction management. Seventy-nine studies were selected and comprehensively analyzed. The authors conducted a bibliometric analysis to comprehend the spatiotemporal distributions of the selected studies. Then, the selected studies were classified into three categories: (1) progress control, (2) quality control, and (3) safety management. The authors also synthesized information for XR applications in various construction management scenarios and summarized the challenges related to XR applications. Finally, this review shed light on future research directions of XR for safe and effective construction management.

Limitations in Current Construction Practices of Public Sector Building Projects in Sindh

Undivided attention is being driven by construction productivity in today’s era. The main and the foremost concern of any organization is its construction productivity. The discovery of factors impacting construction productivity has been the subject of much research. For a very long time, research has sought to identify the key elements influencing building productivity in various nations. Continuous work in this approach has led academics to identify a wide range of factors. While the subject of this paper is however has been limited to Sindh province of Pakistan only. The construction industry of Pakistan is swelling with each passing day thus construction productivity is of the major concern. This paper aims at exposing the key weakness in current construction practices being employed in various building projects of Sindh. For this purpose, 135 questionnaires, after a rich literature survey, were distributed among the industry experts and the obtained results were analyzed and then ranked in Statistical Packages for Social Sciences (SPSS). It was revealed through the results that 10 factors chiefly influence the construction productivity which are shortage of unskilled labor, payment delay, less salary, insufficient modern tools, delay in delivery of material at site, material shortage and quality, labor absenteeism, equipment breakdown, experience of contractor and construction technology. At the end of the study, it is recommended that a framework maybe developed based upon the factors given above to improve the construction productivity of the building projects of Sindh.