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Urban heritage is a precious asset for humanity, reflecting its accomplishments over the eras. There are many buildings and heritage sites that have been lost due to lack of interest in documenting and preserving them. At this present time, when the information about these buildings and heritage sites are available, that leads to make studies for virtually rebuilding them. The aim of this study is to use modern technology to virtually rebuild and document the data of the old market of Domat Al-Jandal, and make a virtual rebuilding of the market, to be a strong historical addition to this archaeological area as it was before. This historical market was one of the most famous old markets in the Arabian Peninsula, which was destroyed in 1974 as a result of urban development and the absence of development strategies to protect the market's urban heritage. The author digitally documents and preserves the market for architectural, urban, construction, and other purposes. The study includes a set of important steps, beginning with collecting information from different sources about the old market through interviews and collecting both of old and new aerial photographs for the case study site. Computing software and 3-D digital modeling technology are then used to virtual rebuilding of the market and document it via a virtual reality system using real materials. Finally, this study provides details related to the features and terrain of the ancient Dumat Al-Jandal market. The study showed that the reconstructed market will consist of two parts with 42 shops, 33 shops facing on the corridor of market`s piazza, and 9 of which were with piazza-facing entrances.

The nature of soil varies horizontally as well as vertically, owing to the process of the formation of soil. Thus, ensuring the safe design of geotechnical structures has been a major challenge. In shallow foundations, conducting field tests is expensive and time-consuming and often conducted on significantly scaled-down models. Empirical models, too, have been found to be the least reliable in the literature. The study proposes AI-based techniques to predict the bearing capacity of a shallow foundation, simulated using the datasets obtained in experiments conducted in different laboratories in the literature. The results of the ELM-EO and ELM-PSO hybrid models are compared with that of the ELM and MARS models. The performance of the models is analyzed and compared with each other using various performance parameters. The models are graded to each other using rank analysis and the visual interpretations are provided using error matrices and REC curves. ELM-EO is concluded to be the best performing model (R2 and RMSE equal to 0.995 and 0.01, respectively, in the testing phase), closely followed by ELM-PSO, MARS, and ELM. The performance of MARS is better than ELM (R2 equals 0.97 and 0.5, respectively, in the testing phase); however, hybridization greatly enhances the performance of the ELM and the hybrid models perform better than MARS. The paper concludes that AI-based models are robust and hybridization of regression models with optimization techniques should be encouraged in further research. Sensitivity analysis suggests that all the input parameters have a significant influence on the output, with friction angle being the highest.

Public projects in Saudi Arabia have faced performance issues. The primary procurement system used in Saudi Arabia (low-bid) does not consider the contractors’ performance. A case study conducted at a university campus in northern Saudi Arabia showed low project performance. The current procurement system was analyzed and modified to utilize the concepts of the Best Value Performance Information Procurement System (BV PIPS). BV PIPS has demonstrated high levels of project performance in previous tests. A large survey was conducted of 761 classified contractors and 43 universities’ representatives. Survey respondents were asked to quantify their view regarding the current procurement system, rate their level of agreement regarding Best Value principles, and rate their level of agreement with the newly proposed procurement system which integrates Best Value principles. The results of the survey show that both, clients and contractors, are dissatisfied with the current procurement system, and agree with the new procurement system. The survey also suggests that respondents agree with Best Value principles suggesting that contractors’ performance should be tracked, and procurement should be conducted using both price and past performance information. The authors recommend that the newly proposed procurement model should be implemented in more projects in Saudi Arabia to further validate the Best Value system and improve the performance of projects in the country.

Public projects in Saudi Arabia have been experiencing low construction project performance for the past decade. Studies have identified the low-bid delivery method as an important factor in causing such delays. In addition, low bids for contracts have not reflected the actual project cost. A case study was conducted at a university campus in northern Saudi Arabia in which the actual project costs for four projects were examined. The study found that all four projects’ costs were higher than the original bid. In addition, a large survey was conducted of 804 classified contractors and universities representatives who identified change orders as the most common factor causing cost overruns in Saudi Arabia. Previous studies showed that some contractors aim to submit low bids for winning the competition then change orders to reduce their losses. Consequently, low bids also lead to cost overruns. In a comparison using the result of a case study and the results of the Performance Information Procurement System (PIPS), Saudi Arabia’s delivery system was identified as a potential cause of project performance issues.

Unreinforced masonry (URM) is one of the most popular construction materials around the world, but vulnerable during earthquakes. Due to its brittle nature, the URM structures may lead to a possible collapse of the wall of a building during earthquake events causing casualties. In the current research, an attempt is made to enhance the seismic capacity of URM structures by proposing a new innovative composite material that can improve the shear strength and deformation capacity of the URM wall systems. The results revealed that the fiber-reinforced plastic having high tensile and shear stiffness can significantly increase in-plane as well as out-of-plane bending strength of the URM wall. It was recorded that the bending moment of the prism increased up to 549.5% by increasing the bending moment from 490 N*mm to 3183 N*mm per mm deflection of prism upon using glass fibers. Moreover, the ductility ratio amplified up to 5.73 times while the stiffness ratio increased up to 4.16 times with the aid of glass fibers. Since the material used in this research work is low cost, easily available, and no need for any skilled labor, which is economically good. Therefore, the URM walls retrofitted with fiber-reinforced plastic is an economical solution.

This study aims to investigate the two-way shear strength of concrete slabs with FRP reinforcements. Twenty-one strength models were briefly outlined and compared. In addition, information on a total of 248 concrete slabs with FRP reinforcements were collected from 50 different research studies. Moreover, behavior trends and correlations between their strength and various parameters were identified and discussed. Strength models were compared to each other with respect to the experimentally measured strength, which were conducted by comparing overall performance versus selected basic variables. Areas of future research were identified. Concluding remarks were outlined and discussed, which could help further the development of future design codes. The ACI is the least consistent model because it does not include the effects of size, dowel action, and depth-to-control perimeter ratio. While the EE-b is the most consistent model with respect to the size effect, concrete compressive strength, depth to control perimeter ratio, and the shear span-to-depth ratio. This is because of it using experimentally observed behavior as well as being based on mechanical bases.

Based on modified methods for the results of first-order analysis of RC columns, different codes approximate the second-order effects by using equations focusing on the maximum additional moment through the column height. These equations did not refer to the additional moments between the column and the connected beam, only the effect of the connected beams is taken into consideration by dealing with the effective length of the column, not the total length. Moreover, these equations did not take into account the second-order effect, which is caused by axial force and the inverse moments due to beam restriction for the column ends. This paper presents a new moment magnifiers matrix for the additional moments at the connection between braced columns and the connected beams as a simplified computation that can be used in the design procedure. That is through an equation based on transforming the original long column in second-order analysis to an equivalent isolated column. The equivalent column was represented as an element restricted with rotational spring support at its ends, and it is subjected to lateral distributed loads that have the same influence of the second-order effect on the induced additional moments in the long column. The suggested equivalent column can be used to form the additional bending moment diagram, also to compute the additional deformations as well. Numerous factors were analyzed linearly by using the presented new moment magnifiers matrix and finite element method, and the results proved the efficiency of the proposed model. Although the presented suggested model is based on the isolated analysis of the long column, the effect of the additional moments in the adjacent long column can be considered by presented two suggestions to improve the model. Also, development was proceeded on the model by modifying the flexural rigidity (EI) which is recommended in ACI to appropriate the time of failure. The additional moment values of the developed model were close to the values calculated by the ACI equation.

Formulation of high-performance cement mortar matrices reinforced with varying aspect ratios of carbon nanotubes and carbon fibers have been devised. Investigations on comparative effect of varying aspect ratios of carbon nanotubes and carbon fibers, with varying loads at two different water to cement ratios (w/c) of 0.45 and 0.50 in cement mortar matrices, were studied for the fracture response of the composites in crack initiation and propagation phases. The experiments concluded that an optimum addition of carbon nanotubes results in substantial improvements in terms of fracture properties. However, in case of carbon fibers, optimum increase in flexural strength was attained for carbon fibers having 12 mm length with 0.45 w/c, with the inclusion percentage of 0.15 by weight of cement indicating the increase in flexural strength up to 62.47%, followed by carbon fibers of 6 mm length at 0.45 w/c with the increase of 41.02%. Research also provides novelty for selection of optimum formulations among different aspect ratios. The field emission scanning electron microscopy evidenced a uniform level of tubes/fibers dispersion, the effective reinforcing effect by the tubes/fibers on the host matrix by providing the fracture mechanics phenomena of crack initiation, crack suppression, crack bridging and fiber–matrix debonding.

The characteristics of the unbound base layer have been recognized to influence the performance of flexible pavements to wide extents depending on climate conditions, construction quality, material source, traffic level, and pavement structure. Recently, unsaturated soil modeling has become generally accepted in predicting the pavement performance as pavement layers are typically placed well above soil water table, and tend to remain unsaturated during pavement service life. This paper investigates the combined impact of compaction level and initial matric suctions of construction and demolition (C&D) waste material used as a based layer on simulated pavement performance using the AASHTOWare Pavement ME Design software. Towards the preparation of the software inputs as per level 1 requirements, a laboratory experimental program was conducted on C&D material which includes the construction of soil water characteristic curve (SWCC) and determination of resilient modulus at four different moisture contents and two levels of compaction effort. The simulated pavement performance analyses consider two climatic conditions (dry and wet), two groundwater table levels (shallow and deep), two types of subgrade soil (strong and weak), and two thickness levels for the base and asphalt surface layers (thin and thick). Full statistical analyses of the main and interaction effects were performed on the results of AASHTOWare Pavement ME Design software. The results showed that the compaction level has more significant effect on the base and subgrade rutting and bottom-up fatigue cracking than the initial matric suction. In addition, both initial matric suction and SWCC input level were found to have a significant effect on all simulated distresses. Furthermore, the interaction between the compaction and initial matric suction was found to be significant.

Research has shown that public construction projects in Saudi Arabia have exhibited poor performance for the past three decades. Recent studies have identified the ownership of parties who cause risks and lead to low performance in the Saudi construction industry. These studies identified that contractors are not the main party that cause risks as owners, consultants, and other parties have the major share of causing risks in the industry. The aim of this study is to assess the current risk management and performance measurement practices applied by contractors to minimize risk out of their control (caused by other parties) through conducting a questionnaire survey. The questionnaire survey was sent to contractors who work in public construction projects in Saudi Arabia. The assessment included the contractors’ practices in the identification of projects activities and risks, contractors’ practices in mitigating other parties’ activities and risks, and contractors’ practices in measuring the performance of all project parties. The study identified that contractors’ current risk management and performance measurement practices are not effective in minimizing projects risks caused by other parties and ineffective in measuring performance of all parties. The study recommends a proactive risk management approach that can help contractors to minimize risks caused by other parties and can measure the performance of all parties in projects.

In this research, a suggested linear model was investigated to analyze the plastic stage for indeterminate skeletal steel structures. The aim of this model is to facilitate the analysis of the structure element in the plastic stage without resorting to the complicated calculations of the material nonlinearity. The suggested model was represented by considering the full plastic sections in the element as a concentrated plastic hinge. The plastic hinge was modeled instead of the plastic zones as a pin support or an intermediate hinge with a rotational spring. Computing the stiffness of rotational spring was based on the acceptance criteria in the nonlinear static analysis according to FEMA 356 (2000). The linear structural methods can be used after that to calculate the deformations and moments in plastic stage. In this paper and due to the simple cases which are analyzed, the forced method of structural analysis can be used. But for structural elements which are more complicated than the present cases where the plastic hinges are separated on more positions, the finite element analysis is the best. The suggested model can be used to predict the mechanism of failure, to evaluate the deformations after occurring the plastic moment as well as to compute the elastic redistribution moments. The suggested model was verified by comparing the experimentally and analytically results of steel beam deformations which made by El Damatty (J Steel Compos Struct 3:421–438, 2003) with the obtained results of the suggested model, and the suggested model gave good results. Moreover, a W-shaped fixed steel beam was analyzed by finite element method by using ANSYS program, the suggested model and elastic analysis to compute the induced moments in plastic stage and evaluated the elastic redistribution moments. The suggested model gave matching values of the induced moments of the fixed compared with the finite element results.

Geo-foam is an expanded polystyrene (EPS) or extruded polystyrene manufactured into large lightweight blocks. EPS Geo-foam density is only about 1% that of soil and rock, making it a superior, ultra-lightweight fill material that significantly reduces the stress on underlying subgrades. The lighter load can reduce settlements and can improve stability against bearing and slope failures. Geo-foam offers special advantages for construction on soft ground, slope stabilization, and retaining walls. A parametric study is carried out using ADINA program, different values of Geo-foam thickness (t), and Geo-foam height (H). Loaded and unloaded retaining wall models are also studied. The study aims at achieving the lowest possible stresses in both soil and the retaining wall body. This will reduce the expected soil settlement. Results showed that the most effective and preferable value of the Geo-foam thickness (t) is equal to 1.00 m. Numerical results pointed indicated that the decrease in soil settlement was about 35% when using Geo-foam of thickness equal to 1.00 m. Also, results showed that soil settlements and lateral stresses decreased by about 20% for loaded cases for different values of the Geo-foam thickness when compared with unloaded ones.

Saudi Arabia has been facing issues with completing construction projects on time and on budget. It has been documented that 70% of public construction projects are delayed. A case study was performed at a University campus in northern Saudi Arabia, identifying the major causes of project delays. The University was experiencing delays from 50% to 150%. The delay factors were gathered from the University Projects Director. The University's delay factors were then compared to delay factors experienced on Saudi construction projects, identified by performing a literature research. The comparison identified nine causes of delays that both studies documented. The study also proposes a solution to minimize the nine major delay factors. A literature research identified one construction management method, the Performance Information Procurement System (PIPS), has documented multiple times its ability to improve project performance and minimize delays.

Saudi Arabia has been facing issues with completing construction projects on time and on budget. It has been documented that 70% of public construction projects are delayed. A case study was performed, at a University campus in northern Saudi Arabia, identifying the major causes of project delays. The University was experiencing delays from 50% to 150%. The delay factors were gathered from the University Projects Director and five engineers. The University delay factors were then compared to delay factors experienced on Saudi construction projects, identified by performing a literature research. The comparison identified nine causes of delays that both studies documented. The study also proposes a solution to minimize the nine major delay factors. A literature research identified one construction management method, the Performance Information Procurement System (PIPS), has documented multiple times its ability to improve project performance and minimize delays.