MPa Compressive Strength Research Articles

Acid and Sulphate Attacks on a Rubberized Engineered Cementitious Composite Containing Graphene Oxide.

The objective of this research was to determine the durability of an engineered cementitious composite (ECC) incorporating crumb rubber (CR) and graphene oxide (GO) with respect to resistance to acid and sulphate attacks. To obtain the mix designs used for this study, response surface methodology (RSM) was utilized, which yielded the composition of 13 mixes containing two variables (crumb rubber and graphene oxide). The crumb rubber had a percentage range of 0–10%, whereas the graphene oxide was tested in the range of 0.01–0.05% by volume. Three types of laboratory tests were used in this study, namely a compressive test, an acid attack test to study its durability against an acidic environment, and a sulphate attack test to examine the length change while exposed to a sulphate solution. Response surface methodology helped develop predictive responsive models and multiple objectives that aided in the optimization of results obtained from the experiments. Furthermore, a rubberized engineered cementitious composite incorporating graphene oxide yielded better chemical attack results compared to those of a normal rubberized engineered cementitious composite. In conclusion, nano-graphene in the form of graphene oxide has the ability to enhance the properties and overcome the limitations of crumb rubber incorporated into an engineered cementitious composite. The optimal mix was attained with 10% crumb rubber and 0.01 graphene oxide that achieved 43.6 MPa compressive strength, 29.4% weight loss, and 2.19% expansion. The addition of GO enhances the performance of rubberized ECC, contributing to less weight loss due to the deterioration of acidic media on the ECC. It also contributes to better resistance to changes in the length of the rubberized ECC samples.

PENGARUH PENGGUNAAN TANAH MEDITERAN SEBAGAI BAHAN SUBSTITUSI SEMEN TERHADAP KUAT TEKAN DAN TARIK BETON

Title: The Effect of Using Mediteran Soil as Cement Substitution Materials in Compressive Strength and Tensile Strength of Concrete Concrete is a composite material (mixture) of cement, fine aggregate, coarse aggregate, and water. The potential of limestone in Indonesia is very large, reaching 28.678 billion tons which is the main ingredient in the cement manufacture. In the long run it will be depleted because it is a non-renewable natural resources. So to reduce the use of limestone the utilization of Mediteran soil as a substitution for some cement in the manufacture of concrete is required. The initial idea is based on the chemical composition contained in the Mediteran soil almost identical to the cement, which is carbonate (CaO) and silica (SiO2). The purpose of this research is to reveal the influence of substitution of Mediteran soil by 20% and 40% in the compressive strength and tensile of the concrete at age 3, 7, 14, and 28 days with the number of test specimen each 3 pieces on each variation in 10cm x20cm cylinder with planning of concrete mixture refers to SK SNI method T-15-1900-03. The type of research used is quantitative with the experimental method of laboratory test and data analysis of comparative method and regression. The results show that compressive strength and tensile strength of concrete using Mediteran soil substitution comparable to the strength of normal concrete with dry treatment. In the composition of 20% Mediteran soils decreased by 51.35% or 7.9 MPa (compressive strength) and 30.60% or 0.93 MPa (tensile strength). While the composition of 40% Mediteran soil decreased by 43.78% or 9.13 MPa (compressive strength) and 2.24% or 1.31 MPa (tensile strength).

An Experimental Study on the Dynamic Behavior of an Ultra High-Strength Concrete

Ultra-high-strength concrete is a newly developed construction material that has a minimum 120 MPa or higher compressive strength. Recently, the usage of high-strength and ultra-high-strength concretes has become widespread due to the enhancement of the concrete technology. Many civil engineering structures constructed by using concrete materials are usually subjected to, in addition to static loads, dynamic loads due to earthquakes, wind and storm, impact and blast, which take place under high energy and high strain rate values. The effects of such loadings on the structure must be understood thoroughly. In recent years, the withstanding of a structure on these loading conditions has become a crucial issue for its impact on the economy and human safety. One of the approaches to fulfill these requirements is to develop high-strength or ultra high-strength concretes (UHSCs). In this study, an ultra-high-strength concrete with a compressive strength of 135 MPa was designed and developed. In order to determine the dynamic behavior of this UHSC, the specimens at three height/diameter ratios (approximately, 0.6, 1.0 and 1.2) were extracted from the prepared concrete mixtures. These concrete specimens were tested to determine both the quasi-static and dynamic compressive behaviors of the developed concrete. In the quasi-static compression tests, cylindrical specimens and a conventional compressive testing machine were used. In order to study the dynamic compressive behavior, a Split Hopkinson Pressure Bar (SHPB) test setup was used. In this test system, the time variations of compressive strength, the strain and strain rates under uniaxial pressure loading were experimentally evaluated and the deformation and fracturing processes of the specimens were recorded using a high-speed camera. The test results, based on the testing of 21 different specimens, have shown that the dynamic compressive strength values of the developed concrete varied in the range of 143 to 253 MPa, while the strain rate values varied in the range of 353 s−1 to 1288 s−1. Using the data generated in the SHPB tests, the parameters present in a Johnson–Holmquist–Cook concrete material model, which is used in numerical studies on the high strain rate behavior of concretes, were evaluated.

Design of the RFX-mod2 first wall

RFX-mod2 is the latest upgrade of the reversed field pinch machine operated at Consorzio RFX. A significant modification consists of replacing the first wall tiles, proposed as a key factor to improve the gas density with reduction of hydrogen retention. Polycrystalline graphite has been identified as tile material given its high thermal conductivity (up to about 165 Wm−1 K−1), uniformity and small grain size (about 20 μm), and high mechanical strength (100 MPa compressive strength, 30 MPa tensile strength).With respect to RFX-mod, the mechanical resistant section of tiles has been increased coherently with the magnetic front-end modification that foresees the tiles supported by the existing MHD passive stabilising shell, so decreasing the maximum stress at 3.5 MPa calculated from finite element analysis that simulates the operating condition. This low stress level together with a measurement of the experimental loads during next RFX-mod2 operations could qualify the use of extruded graphite for a possible further first wall change in the future. Indeed, extruded graphite is considered attractive given its high directional thermal diffusivity (about 50 % better then polycrystalline graphite) to enhance the heat transmission and so improving the gas density control, and the low stress induced may allow use of this mechanically less performing graphite.

Sustainable use of industrial-waste as fine-aggregate of Foam Concrete

The benefits of using industrial waste as a replacement for natural sand and cement in light-weight concrete are also discussed. The paper presents the use of fly ash and blast furnace slag to replace 100% sand in foam concrete with a wet density of 1700 kg/m3 and 900 kg/m3 as well as their mechanical properties. The absolute volume method was used to calculate the ratio of foam concrete mixture. Besides, the foam concrete mechanical properties are determined according to the Russian standard GOST 10180-2012. Research results indicate that at the age of 28 days with Series I, the value of compressive strength obtained from 13.91MPa to 42.35 MPa, flexural strength from 0.53 MPa to 1.06 MPa and water absorption between 0.92% and 5.78% with Series II these values from 1.69 MPa to 8.22 MPa for compressive strength, from 3.25 MPa to 6.72 MPa for flexural strength and the result for water absorption is in the range of 12.35% and 22.16%. Besides that, research results also indicate that the correlation between dry density and compressive strength has a positive linear relationship. The results of this study have proved that foam concrete uses fly ash and blast furnace slag can replace traditional concrete in construction as well as replacing clay bricks will not only improve concrete strength but also reduce costs as well as protect the environment.

Effect of raw material forms on the microstructure and mechanical properties of MoNbRe0.5TaW high-entropy alloy

MoNbRe0.5TaW high-entropy alloy with different raw material forms was synthesized using arc-melting technique. The alloy melted with bulks or powders shows different microstructure and mechanical properties. The MoNbRe0.5TaW alloy has a single body-centered-cubic (BCC) solid solution when melting metal bulks. When melting the mixture of metal powders at the same process parameters, this alloy consists of BCC solid solution and oxide particle phase. However, the particle phase disappears and the alloy turns to single BCC phase as increasing the re-melted times. The formation and element segregation of the BCC solid solution match well with the computer-aided thermodynamic calculation. The precipitation of metastable oxide particles is mainly due to the oxidation of powders originated from their high surface energy. The MoNbRe0.5TaW alloy with oxide phase shows high Vickers micro-hardness of 5674 ± 92 MPa, high yield strength of 1145 ± 10 MPa and ultimate compressive strength of 1324 ± 18 MPa. The strength mechanism is Orawan strengthening. This study provides guidance for the design and preparation of high-entropy alloys with high performance.

Synergic Effects of Magnetic Nanoparticles on Hyperthermia-Based Therapy and Controlled Drug Delivery for Bone Substitute Application

Three-dimensional bio-nanocomposite scaffolds using bioactive wollastonite and bioglass as the base materials are composed with 0 (as the control), 5, 10, and 15 wt% of magnetic nanoparticles (MNPs) with space-based agents sodium bicarbonate (NaHCO3). The process, in this study, is performed by homogenizing and mixing MNPs, wollastonite, and bioglass, after high-energy ball mill, pressing at 150–200 MPa, and kept at 900 °C, which eventually produced scaffolds with 20–40% porosity. Additionally, X-ray diffraction (XRD), scanning electron microscopy (SEM), and mechanical testing including compressive strength are investigated. The size of the powder and scaffold crystals size are measured between 30 and 50 nm, and the pores are measured between 70 and 180 μm. The results show that the best mechanical properties of the specimen belong to the sample containing 15 wt%, with 7.9 ± 0.5 MPa and 203.3 ± 5 MPa of compressive strength and elastic modulus, respectively. Besides, the biological evaluation confirms that the sample with 10 wt% MNPs presents a better apatite formation on porous scaffolds, after 28 days in SBF solution. The obtained results indicate that the samples with 10 and 15 wt% MNPs illustrate proper mechanical and biological responses for bone tissue application. The samples having sodium chloride space agent present an open porous architecture in comparison with the sample containing sodium bicarbonate space agent. Moreover, in this study, the global criterion method (GCM) has been used to find the best combination of nanocomposite scaffold having the optimal mechanical and biological properties. The total porosity of the fabricated scaffold is similar to real bone architecture and can be a useful option for cancer therapy and insert in the bone sarcoma tumor.

Performance Evaluation of Cost-Effective Non-autoclaved Aerated Geopolymer (NAAG) Blocks

Owing to the increased population in developing country like India, the demand of sustainable building material is likewise increased to meet its excessive consumption. In the present study, non-autoclaved aerated geopolymer (NAAG) blocks were developed using industrial waste [fly ash, granulated blast furnace slag (GGBS)], foam and aerating agents with less concentration of alkaline solution (i.e. 1.5–4 M) and tested for their physio-mechanical properties. These NAAG blocks achieved up to 13.5 MPa compressive strength. Optimized samples were tested for thermal and durability related properties. Performance evaluation of NAAG blocks exhibited low thermal conductivity and durable nature as compared to the clay bricks. This developed NAAG block is proven to be a cost-effective and energy effective solution and can be used as building material.

Performance of Crumb Rubber and Nano Fly Ash Based Ferro-Geopolymer Panels under Impact Load

This paper presents an experimental investigation into the impact performance of Ferro-cement panels incorporating a significant proportion of geopolymer mortar. This panel could be an effective replacement for prefabricated roof and floor deck construction elements. In this study, the geopolymer mortar includes wastes disposed from industries like ground granulated blast furnace slag (GGBFS) and flyash as their base material which contributes to reduced CO2 emission. The pore filling and element densifying mechanism is enhanced by the addition of Nano flyash. The fine aggregate is replaced up to 5% with treated tyre crumb rubber which can be utilized as a sustainable construction material. The cast panel was cured at 80oC for 48 hours in the oven. The incorporation of Expanded Metal Mesh into geopolymer mortar results in higher impact load absorption capacity rather than other kind of reinforcing meshes. The GGBFS based Geopolymer results in 17% higher compressive strength than fly ash based geopolymer because of its good bonding nature. The Nano fly ash based geopolymer gives 35 MPa in compressive strength and 902.52 joules in impact energy absorption which is greatest among all panels because of its densifying effect of mortar.

A high-strength lightweight concrete made using straw

This experimental work aims to develop an eco-lightweight concrete with excellent mechanical and thermophysical properties using straw. Thus, this paper considers the use of a formulation of an ultrahigh-performance concrete based on dune sand, with the introduction of up to 20 kg/m3of straw. The study investigates the mechanical and thermophysical properties of the obtained high-strength lightweight concrete and examines the effects of the straw length. The results show that, depending on the amount of straw used, a decrease of up to 33% of density and 60% of thermal conductivity is noted. Moreover, despite increasing the straw content, which reduces the mechanical strength of the concrete, interesting strength values are noted; for instance, values varying from 42 to 59 MPa in compressive strength and from 3·2 to 5·3 MPa in flexural strength for 2 cm of straw length are obtained.

Alkali-activated binder as stabilizer in compressed earth blocks

Compressed earth blocks (CEB) has number of advantages: cost and energy efficient, eco-friendly, non-toxic, and fireproof. It is composed of available compressed soil near project site with binders as stabilizers. From literature, adding ordinary Portland cement (OPC) as stabilizer is practiced. However, the use of OPC produces high carbon footprint in its production phase. This paper aims to use Alkali-activated (AA) binder as stabilizer for the CEB to promote sustainable construction. It uses a combination of fly ash (FA) mixed with Sodium Hydroxide (NaOH) to produce the stabilizer. Compressive strength and water absorption using AA binder as stabilizer in CEB are investigated. Total of fifty-two CEBs with dimensions of 295mm x140mm x100mm are made as an alternative to conventional concrete hollow blocks with a minimum value of 2.50MPa compressive strength from the provision of Philippine National Standard (PNS). The AA binder ratio of 5% and 15% produced compressive strength of 0.42MPa and 2.92MPa, respectively. Additionally, AA binder ratio of 10% produced lowest percentages of water absorption at 12.83%. It shows that the use of CEB with AA binders is possible in achieving sustainable construction building materials.

Proposed mix design method for sustainable high-strength concrete using particle packing optimization

A sustainable approach to concrete mix design is essential for the construction industry since it is one of the major sectors responsible for CO2 emissions worldwide. The use of high-strength concrete (HSC) is an eco-efficient alternative concrete solution since it requires lower binder contents per unit of compressive strength. The objective of the present work is to propose a new mix design method for sustainable HSC wherein cement consumption and CO2 emissions are reduced in comparison to HSC designed using existing mix design methods. In the proposed method, the proportions between fine materials and aggregates are based on particle packing technics. The method was validated by producing a HSC using both silica fume and stone powder as mineral admixtures, as well as a mix of one fine and two coarse aggregates. The results indicate that a compressive strength of 104 MPa and a dynamic modulus of elasticity of 60 GPa were obtained with 336 kg/m3 of cement. This represents a cement consumption of only 3.2 kg to deliver 1 MPa of compressive strength. Notably, this value is lower than the values obtained in the literature for HSC, thus demonstrating that the proposed method enables the production of more sustainable HSC. Furthermore, all studied concretes presented very high workability (slump>200 mm), excellent quality according to the ultrasonic pulse velocities (>5150 m/s) and insignificant corrosion risk due to the electrical resistivity test (>200 KΩcm). These results demonstrate that—in addition to producing more sustainable HSC—the proposed method allows concrete to achieve the required parameters in both fresh and hardened states.

Lateritic soil based-compressed earth bricks stabilized with phosphate binder

This work aimed to investigate the possibility of using binder obtained from calcined laterite and phosphoric acid as a novel stabilizing for the manufacturing of compressed earth bricks (CEB). Various proportions of binder from up to 20 wt% were used to stabilize the soils. Fourier Transformed Infrared Spectroscopy (FTIR), X-ray diffraction (XRD) thermal analysis (TGA-DSC), Scanning Electron Microscopy (SEM), water absorption and compressive strength tests were used to characterize the obtained products. The results showed that CEBs developed are highly resistant (similar to concrete) with dry compressive strength ranging from 17 MPa to 38 MPa and wet compressive strength from 6.3 MPa to 16.9 MPa. All the CEBs are also water-resistant and the water absorption was between 9.36-14.18 %. The increase of the binder content improves the performance of the compressed earth bricks. The new binder developed, which is based on the ferro-silico-aluminophosphate network, is effective for the stabilization of the lateritic soil for producing compressed earth bricks.

In-situ synthesis and superhigh modulus of network structured TiC/Ti composites based on diamond-Ti system

Abstract In order to enhance the elastic modulus and strength of titanium, novel continuous network structured TiC particle reinforced Ti (TiC/Ti) composites were successfully fabricated by hot pressing sintering based on diamond-Ti system. The results showed that 5 vol% fine diamond powders can be homogeneously adhered onto the surface of large Ti powders by lower energy ball milling process of 250 rpm/5 h/3:1. The mixed powders resulted in equiaxed network microstructure of TiC/Ti composites formed by continuous TiC particle reinforcement around large Ti powders after in-situ reaction between diamond and Ti. However, high energy ball milling process of 300 rpm/10 h/10:1 must be employed due to excessive diamond powders, which can result in TiC/Ti composites with a novel flattened network microstructure. Among the composites, the one introduced by 10 vol% diamond exhibited the highest elastic modulus of 184 GPa, which was increased by 64% compared with pure Ti (112 GPa). The composites with 5 vol% and 7.5 vol% diamond presented 830 MPa and 1480 MPa compressive yield strengths respectively, which were 1.9- and 3.4-fold that of pure Ti (429 MPa). The superior elastic modulus and strength of the composites was mainly attributed to the continuous TiC network microstructure and remained reinforcement-lean region based on the Hashin-Shtrikman theory.

Production of a lightweight masonry block using alkaline activated natural pozzolana and natural fibers

Lightweight geopolymers are alternative low-carbon footprint building materials with high potential to produce value added products for the construction industry such as low-density masonry units. This work focuses on presenting the development of a new lightweight masonry block using natural pozzolana-based geopolymer mortar, hydrogen peroxide as a foaming agent and jute fibers as reinforcement additive. The experimental plan allowed the optimization of the production process and the definition of the optimum quantities of hydrogen peroxide content, pozzolana: fine aggregate ratios and the appropriate amount of fibers to be incorporated. The experimental results demonstrate the feasibility of the production of new masonry units, which can achieve up to 8.1 MPa of compressive strength after 28 days of fabrication with reduced bulk densities of 1269 kg/m3.

Performance of Substrate Reinforced Concrete Slabs with Geopolymer Concrete Overlay

Geopolymer concrete (GPC) has been used increasingly in recent years and has been applied to various structural components. Considerable interest has been developed in using geopolymer in concrete to increase the load carrying capacity of the structural members in service. It has been used recently to increase the flexural capacity of concrete slabs by applying overlay layer of GPC onto an existing slab, a technique known as cement base bonded overlay. The objective of this research is the investigation of the flexural behavior of substrate cement reinforced concrete (RC) slabs with a GPC overlay. Seven RC slabs with 300 x 1700 x 100 mm, 33 MPa compressive strength after 28 days and reinforced with steel with a diameter of 8 mm. Because the performance of these composite slabs depends on the bonding between the substrate and overlay concrete, six different techniques were used for preparing the RC substrate surfaces including, (as smooth as cast (AS), carving 2mm width and 1 mm deep (Carv), dowels 8 mm Z section (DZ), painting with epoxy resin on the surface (ER), surface roughened by a stiff brush in both the transverse and longitudinal directions (T&L) D and surface roughened in the transverse directions by a stiff brush (TD). The evaluated properties were load-deflection relationship, strain distribution curves and the interface slip.Based on the experimental tests, the ductile performance of the slab depends not only on adding GPC to the topping but mainly on the type of interface roughness. Moreover, the ductility ratio may be arranged in desponding order as (TD), (T&L) D, (ER), (Carv), (DZ) and (AS). The biggest slip happened for slab control at 0.25mm, signifying poor bonding strength at the interface. Slab (L&T) D, with zero mm of slippage, showed the best interface slip.

MECHANICAL PROPERTIES OF RICE HUSK ASH (RHA) BRICK AS PARTIAL REPLACEMENT OF CLAY

Clay has been used as main material in fabrication of bricks however the use of waste materials in brick manufacturing has been introduced for conservation of dwindling clay resources, as well as preventing environmental and ecological damages caused by quarrying and depletion of raw materials. Bricks that available in some regions have poor quality, low compressive strength, higher water absorption and uneven surfaces Therefore in this study, rice husk ash has been utilized for the preparation of bricks in partial replacement of clay. The specimens were cast with different replacement levels of clay varying as 0%, 5%, 10%, 15%, and 20% with rice husk ash. The specimens were tested for water absorption and compressive strength accordingly to Malaysian Standard EN 1008:2010 for 2 hours. Experimental shows that excessive addition of rice husk ash has higher water absorption and low compressive strength as rice husk ash percentage increases rice husk ash characteristics predominate. The bonding between the clay particle and the rice husk ash particles is weak. By adding 10% of rice husk ash by weight is the best brick properties which 6.80 MPa of compressive strength and 16.30% of water absorption. The water absorption of RHA brick developed did not exceed 20% hence promoted to be partial replacement of clay.

Old Dumped Fly Ash as a Sand Replacement in Cement Composites

The use of industrial residues to replace natural resources for the production of building materials is economically and ecologically justified. Fly ash (FA) taken directly from electro-filters is commonly used as a cement replacement material. This is not the case, however, for old dumped fly ash (ODFA) that has been accumulating in on-site waste dumps for decades and currently has no practical use. It causes environmental degradation, which is not fully controlled by the governments of developed countries. The aim of the study was to assess the possibility of using ODFA as a partial replacement for sand in cement composites. ODFA replaced part of the sand mass (20% and 30%) in composites with a limited amount of cement (a cement-saving measure) and sand (saving non-renewable raw material resources). ODFA was activated by the addition of different proportions of hydrated lime, the purposes of which was to trigger a pozzolanic reaction in ODFA. The quantitative composition of the samples was chosen in such a way as to ensure the maximum durability and longevity of composites with a limited amount of cement. The 28-day samples were exposed to seawater attack for 120 days. After this period, the compressive strength of each sample series was determined. The results suggest the possibility of using ODFA with hydrated lime to lay town district road foundations and bike paths of 3.5 to 5 MPA compressive strength. What is more, these composites can be used in very aggressive environments.

Novel Advanced Composite Bamboo Structural Members with Bio-Based and Synthetic Matrices for Sustainable Construction

This paper experimentally investigates the properties of unprecedented new advanced composite structural members in compressions made of bamboo culms formed with different bio-based and synthetic matrices. Due to extensive CO2 emissions corresponded to the production of construction materials, it is essential to produce high-performance environmental-friendly construction materials from bio-based renewable resources such as bamboo. However, the use of bamboo culms in construction has been hindered by their inherent specific geometric hollow shape. To address this issue, small-diameter bamboo species were used in this study to form solid structural composite cross-sections to desired shapes. An experimental study was conducted on the compressive properties of six composite structural members made of commonly available bamboo species (Phyllostachys edulis or Moso) with different matrices including a bio-based furan resin, a cementitious grout, and epoxy. In order to prevent premature buckling of bamboo components within the engineered columns, and in an attempt to propose a bio-based structural column, three layers of hemp wrap where applied to provide confinement for bamboo culms. The results of the tests confirm that the bamboo-furan and bamboo-grout composite columns both have the potential to reach a remarkable compressive strength of 30 MPa. However, the bamboo-epoxy composite specimen, considering the excellent mechanical properties of the epoxy matrix, delivered a benchmark to demonstrate the potentials of bamboo-based structural sections by reaching 76 MPa compressive strength before crushing. The bamboo-epoxy composite provided new prospects for future work on the 100% bio-based versions of the bamboo-based sections with improved bio-matrices (by using bio-epoxy and improved furan resins with compatible mixes) and innovative confinement types. With the promising results of this study, there is a real opportunity of creating contemporary engineered bamboo-based structures as a sustainable replacement to the existing steel, concrete and timber structures.

Production and Characterization of Hybrid Briquettes from Corncobs and Oil Palm Trunk Bark under a Low Pressure Densification Technique

The objective of this research was to investigate the quality of hybrid briquettes developed from corncobs (CC) and oil palm trunk bark (OPTB) under a low-pressure densification technique. The materials were combined in varying ratios of CC to OPTB (100:0, 75:25, 50:50, 25:75, 0:100) and wastepaper pulp (10% by weight) was added to each mixture as a binder. The briquettes were produced using a manually operated 20-tonne hydraulic piston press at 28 °C temperature and ≤7 MPa compaction pressure. The mechanical strength of the briquettes was determined by the drop test and compression test methods, while a bomb calorimeter was used to determine the calorific values. The results showed that the physical properties of hybrid briquettes ranged from 9.24–10.00% moisture content, 0.38–0.40 g/cm3 density, and 87.60%–92.00% water resistance. Mechanical strength showed a 98.28%–99.08% shatter index and 18.47–21.75 MPa compressive strength, while calorific values ranged from 16.54–16.91 MJ/kg. The hybrid briquettes fared better than the CC briquettes. The significance of this study lies in the production of briquettes with suitable physical, mechanical and thermal properties by utilizing OPTB which have hitherto not been used, mixed with corncobs. This could bring substantial environmental and socio-economic benefits to rural communities of the developing countries.