Angel Antonio Ruiz Pico

27 Water is a precious natural resource, essential for agriculture, livestock, 28 industry and more than that for human consumption. We could say that, if 29 we want our society to continue, we need to guarantee its quantity and 30 quality in every possible way, since its scarcity could be very detrimental. 31 According to this idea, the quality of water in rivers and lakes must be 32 monitored by protection and management services, as it is crucial for the 33 growth and maintenance of natural ecosystems that exist throughout the 34 world. 35 In Latin America, and due to many factors, that produce human activities 36 such as mining, metallurgy and agriculture, pollution problems occur and 37 directly affect the most important resource such as water, to this come the 38 problems caused by heavy metal contamination that in Latin America has 39 worsened steadily over the years. The artificial presence of these pollutants 40 in surface waters is directly affected by this type of activities. For this reason, 41 several studies have been carried out on the presence of heavy metals in 42 rivers, lakes, crops, and soils in urban areas, as well as in environments in 43 the upper areas of river basins and also in coastal areas of several Latin 44 American countries. 45 This article focuses on the analysis of the contamination of the Moche River 46 in Peru due to the presence of heavy metals in the water, and along the 47 entire river that is supplied by this watershed. The contamination is caused 48 by mining, industrial and agricultural activities in the area. The study 49 analyzes the presence of metals such as arsenic, cadmium, copper, lead, and 50 zinc at different points in the river. The results show that the levels of heavy 51 metals exceed national and international standards, which can cause serious 52 health problems for people and animals that consume the river's water or 53 products.

Context: Soils reinforced with natural fibers such as banana fibers (BF) constitute a promising alternative for improving the geotechnical properties of the soil, especially in rapidly growing urban contexts like Peru. Methods: This study was structured into four stages: the extraction and preparation of soil samples; the evaluation of the physical characteristics of the fibers; mixing with proportions of 0.5, 1, 1.5, and 2% BF relative to the soil dry weight; and physical and mechanical tests to assess the effects on geotechnical properties. Results: The addition of 1% BF optimized the properties of the modified soil: the maximum dry density remained stable, the California bearing ratio increased by 5.95%, and the unconfined compressive strength increased by 23.81% compared to natural soil. Conclusions: The use of BF-treated soil meets the local standards for application in infrastructure such as roads and pavements, thus promoting sustainable construction practices and contributing to the development of resilient and environmentally responsible infrastructure.

The objective of this research was to evaluate the physical and mechanical properties of asphalt mixtures using construction and demolition waste (CDW) as fillers for flexible pavement projects designed for light traffic. Asphalt briquettes were produced, incorporating CDW filler, and their performance was assessed in comparison with standard mixtures. The study identified the properties of CDW necessary for its use as filler, determining the optimal percentages to be incorporated into the asphalt mixtures. Mix designs were developed for both the standard sample and for mixtures containing 1, 3, 5, and 7% CDW filler. The results showed that while 1% CDW closely mirrors the properties of the standard asphalt mix and complies with the “General Technical Specifications for Construction” (2013), the optimal performance was achieved at 5% CDW, which exhibited the highest resistance and stability under load. However, not all filler percentages met the required properties for asphalt mixtures, highlighting the importance of proper dosage for effective performance. The findings suggest that incorporating CDW as filler in asphalt mixes can offer a sustainable alternative for flexible pavement construction, provided that filler proportions are carefully controlled.

This paper presents the experimental results performed by SENCICO, based on cyclic loads that were applied to 03 walls of limited ductility brought to failure in laboratory tests. These results were evaluated and processed in order to analyse their performance under controlled lateral loading conditions, to obtain their hysteretic loops representing their stiffness degradation in 13 proposed phases. In turn, the enveloping capacity curves were determined for each specimen in order to obtain a representative curve for the samples. Subsequently, the representative curve is validated through a theoretical calibration with the help of the ETABS® software, adding the nonlinearity to the materials and the mathematical model, obtaining an analytical capacity curve very similar to the experimental one. In addition, a trilinear curve is proposed that fits accurately and represents very well the performance of walls with limited ductility in their elastic, post-cracking and post-creep performance conditions. Finally, the trilinear capacity curve is sectorized in its structural performance levels with their respective threshold drifts, guided by the guidelines proposed by SEAOC VISION 2000.

The nonlinear static analysis method has facilitated models closer to the structural response for strong seismic movements. Therefore, an evaluation of the seismic performance of a multipurpose room building located in a public national university in Chiclayo-Peru was developed by applying nonlinear static analysis, which contains two similar modules of 3 levels each with irregular floors. The structural system of the building is made of bearing walls, it was built in 2010 and was designed according to E.030 (Peruvian earthquake resistant norm) and with the seismic microzoning of Peru. For practical purposes, taking into consideration the symmetry of the global structure, one of the modules was evaluated using nonlinear methods that can simulate the effect of earthquakes on the building using distributed loads on each of the levels. This development included the application of a linear analysis to establish the response spectra and from there implement the nonlinear Pushover analysis. With the results of the analysis, the plastic ball joints of the structural elements of the building were evaluated for both directions. Based on the results, the performance in both directions was determined taking into account the performance levels of HAZUS and VISION2000. The results show a performance of "Life safety" and "Close to collapse" in the X and Y direction respectively, in addition to that, drifts also show a close relation with performance data because HAZUS shows that Y drifts are not favorable, therefore, it is necessary to execute a reinforcement.

Concrete is the most widely used construction material today due to its exceptional ability to withstand compressive forces, commonly referred to as CS. Determining the value of CS for concrete involves conducting various tests, with the uniaxial compression test on concrete specimens being the most used, assessing strength at different time intervals. This research focuses on predicting the value of concrete's CS at 28 days using 16 predictive models based on artificial neural networks, each employing different optimizers, including Adam, Adamax, Rmsprop, and Nadam. Input data includes aggregate properties, cement type, and the proportions of its components, such as water, cement, and aggregates. The neural networks were built using Google's TensorFlow, with two hidden layers that vary in the number of neurons in the first hidden layer (13, 16, 19, 22) and 8 neurons in the second hidden layer. Training was conducted over 400 epochs.The comparison of optimizers reveals that Nadam exhibits the best performance in both the training and prediction stages, with R² values of 0.83 and 0.87 respectively. The increase in the number of input variables in the prediction results in higher accuracy in predicting CS.

The development of nanomaterials in recent years has allowed for the analysis of the possibility of modifying or improving the physical and mechanical properties in concrete manufacturing. Initially, a methodology for the dispersion of nanomaterials was established to homogenize the mixtures. Samples were prepared with varying amounts of MWCNT ranging from 0.05% to 0.25%, in combination with the SNS 360 system at 1% and 2%, alongside a control mix without nano-additions. The samples were fabricated using ordinary Portland cement (OPC) maintaining a water/cement ratio of 0.55. The results indicated a 30% improvement incompressive strength and xx% in tensile strength at 28 days. High compressive strengths were obtained 3 days after its manufacture, acting as an accelerator. At the same time,increasing the percentage of nano materials reduced the slump value and workability. In addition, the permeability decreased significantly compared to standard concrete.Therefore, the concrete mixture with two nanotechnology-based materials demonstrates significant advantages over conventional concrete by being more resistant to compression, traction, exhibiting lower permeability, and achieving high compressive strengths in less time

The useful life of pavements determines the design of asphalt mixtures. However, premature structural failures and low durability are one of the main problems in pavement engineering today. The action of loads produced by traffic, exposure to environmental factors and the inadequacy of conventional designs of asphalt pavements are some of the main problems associated with the durability of the pavement. The modification of asphalt binders is an alternative that has been used for some years to improve the properties of bituminous material. Among the modifying materials are elastomers, a class of polymers with elastic properties that can be heat-treated. In this study, the asphalt was modified by wet means by adding 5, 10 and 15% of Thermoplastic Polyurethane (TPU) by weight of the binder. Subsequently, standard samples were prepared with the characterized constituents and mixtures with the modified asphalt cement. Consequently, tests were carried out to obtain the optimal mixture that improves the properties of conventional pavement. The results show that the optimal TPU addition content is 5%. With this percentage, the modified binder presented a greater elastic recovery of up to 5.60% and a reduction of up to 42.6% in penetration compared to conventional asphalt. In addition, using the Marshall method, it was determined that the stability of the modified mixtures was much higher than that of standard mixtures for light, medium and heavy traffic; so, they will have a higher resistance to deformation and better fatigue behavior.

Large quantities of steel slag are generated annually throughout the world. Some slag from steel manufacturing is reused in the generation of other materials, such as hot mix asphalt aggregate, pipe filling, concrete, among others. The research aims to enrich the mechanical characteristics of soils and minimize road construction costs. The objective of this research is to find a material that increases the mechanical properties of the subgrade in clay soils with different plasticity indices using Electric Arc Furnace Slag (EAF) in percentages: 5%, 15% and 25% of the weight of the soil. From the tests carried out on the soil samples using parameters, it was possible to classify them by the Unified Soil Classification System (USCS) and also by the American Association of Highway Transportation (AASHTO) as low and high clays. plasticity. When testing the samples in their natural state and the samples with EAF, results were obtained that showed an improvement in the physical and mechanical properties of the clay soils with the addition of EAF, increasing the values of the Bearing Capacity Ratio (CBR) and the maximum dry density. of the clay soil as the percentage of HAE in the mixture increased. The optimal HAE addition content corresponds to 25% of the weight of the soil.