Bamboo Splints Research Articles

Učinak uzoraka utora na čvrstoću prionljivosti u betonu ojačanom bambusom

The use of bamboo as a reinforcement material in concrete has garnered attention in recent years due to its low cost, renewability, and high strength-to-weight ratio. However, the bond strength between bamboo and concrete is a crucial factor affecting the overall performance of bamboo-reinforced concrete structures. In this study, the bond between bamboo and concrete is investigated through pull-out tests. Three different groove patterns - rectangular, semi-circular, and V-notch - are examined for their bond strength. Various chemical treatments are also being explored to reduce the water absorption capacity of bamboo splints. The highest bond strengths achieved after using Bond Tite adhesive and bituminous paint are 1.94 MPa and 1.41 MPa, respectively. The findings of this study can be valuable in optimizing the design and construction of bamboo-reinforced concrete structures.

1 g shake table study on seismic strengthening of low-cost rammed earthen houses built of silt enriched soil using natural fiber reinforcement

Earthen houses are practiced as a traditional and low-cost housing in many countries around the globe. These houses were exposed to unacceptable earthquake (EQ) risks despite their environmental benefits. Past earthquakes including the recent past 2017 Tripura EQ has evidenced significant damages mostly in earthen/masonry houses which are built in a non-engineered manner. In this context, the current study aims to investigate the seismic behavior and failure patterns of both unreinforced and using proposed retrofitted rammed earth model houses (with and without openings) built using typical Tripura soils having higher silt content using unidirectional shake table experiments on total 26 physical models. Besides, both seismic strength and structural stability are also examined for retrofitted earthen houses. The study indicates that, proposed novel low-cost natural fiber made textile encasing reinforcement technique has exhibited promising seismic performance of such houses from the view point of structural strength and ductile behavior as compared to traditional cementitious additives and fiber blended stabilized retrofitted houses as well untreated houses. The fundamental lateral period of model unreinforced and reinforced houses found within the range of 0.08 to 0.15 s respectively which indicates increased stiffness of walls due to strengthening may decrease the lateral period maximum up to 46.67%. On the other hand, the maximum increase in seismic strength was observed in order of 4.50 to 6.31 times in the case of bitumen treated bamboo fiber textile based encased houses with L-shaped bamboo splint corner reinforcement whereas traditional cementitious stabilized method has offered maximum 1.13 to 1.83 times increment in lateral strength. Further, the effect of different parametric variations such as area of openings (doors and windows), thickness to height ratio, variation in compaction methodologies on seismic performances of unreinforced rammed earthen houses were also studied in detail. Finally, regression based closed form predictive expressions for seismic strength of rammed earthen houses and without retrofitting are proposed herein. The performed cost analysis study will also help to assess the effectiveness of proposed strengthening techniques.

FLEXURAL AND DURABILITY CHARACTERIZATION OF CONCRETE REINFORCED WITH TREATED BAMBOO AS AN ALTERNATIVE BUILDING MATERIAL

Abstract The cost and environmental problems associated with steel as a reinforcement material in concrete has necessitated the need to research for alternative reinforcement materials, and bamboo is one of them. The flexural and durability characteristics of bamboo reinforced concrete (BRC) samples under harsh environmental condition was simulated by curing samples in an alkaline solution. Bamboo splints that were coated with sanded bitumen were used to reinforce the concrete samples with unreinforced concrete (UC) serving as control. The BRC samples were cured in normal water and an equal number were cured in 5% Sodium Hydroxide (NaOH) alkaline solution. Samples from both curing conditions and another of the control were tested for flexural strengths after 7, 14, 28, 56, and 76 days of curing respectively and results compared. Water absorption rates after each curing period were also taken. Ultrasonic pulse velocity (UPV) tests were also conducted on the samples to find out the composite qualities. The results showed that BRC had twice as much flexural strength than UC but reduced in strength by 17.9% in the alkaline environment after 28 days of curing. In addition to possessing acceptable strength values under normal water and alkaline solution curing situations by ponding, all the samples had elastic dynamic modulus and static modulus values that exceeded minimum recommended values by the relevant standards.

Axial load behavior of unreinforced and reinforced hollow interlocking compressed stabilized earth block masonry walls

This study investigates the axial load behavior of unreinforced and reinforced hollow interlocking compressed stabilized earth block masonry walls. Sixty walls were constructed and tested under axial compression. The variables include block type (unreinforced and coir fibre reinforced), grout condition (ungrouted and grouted), channel blocks, reinforcement type (steel bars and bamboo splints) and configuration (vertical and mesh type). The results show that addition of coir fibres significantly increase the axial load capacity and ductility of walls, regardless of all other variables considered. Grouting of masonry cores increases the load capacity of unreinforced and fibre-reinforced walls (without bamboo/steel reinforcement), however slightly affecting the deflection capacity. The channel block had a detrimental effect on the load and deflection capacity of both unreinforced and reinforced walls. Bamboo/steel reinforced vertically significantly contributed to the axial load and deformability of walls, despite the presence or absence of channel blocks. Both bamboo and steel reinforced walls behaved in a similar manner; yet bamboo splints showing slightly lesser load and deflection capacity than steel. The axial load and deflection capacity of bamboo reinforced grouted walls are about 78.54% to 90.00% and 79.50% to 94.60% respectively as compared to steel reinforced counterparts. Bamboo/steel mesh reinforced walls with channel blocks exhibited better performance compared to corresponding specimens with only vertical reinforcement. However, the improvement was marginal, due to larger spacing between the horizontal reinforcement. Nevertheless, the presence of horizontal reinforcement greatly improved the failure behavior by restraining the buckling of vertical reinforcement. Overall, fibre and vertical steel reinforced grouted wall specimens without channel blocks (FSVRGMW) showed the best performance in terms of compressive strength. The design equations in MSJC-11 predicted the load capacity of unreinforced and reinforced masonry walls more conservatively. Finally, it can be stated that MSJC-11 recommendation of internally reinforced grouted walls must be treated as unreinforced walls, if no horizontal reinforcements was provided, is not reasonable.

Compressive and shear behavior of cement stabilized rammed earth wallettes reinforced with coir, bamboo splints and steel bars

This paper investigates the effect of coir, bamboo and steel reinforcement on the axial and diagonal compressive strength of cement stabilized rammed earth wallettes. Two types of rammed earth wallettes were cast (rectangular and square) to study the failure pattern and effect of different height to thickness ratios on axial compressive strength. Rectangular sample type was tested only under axial compression whereas square sample type was tested under axial as well as diagonal compression. 10% cement stabilizer and 1% coir of 25 mm length were used throughout the experimental program. Experimental results reveal that addition of coir improved the compressive strength of samples by about 17.93% − 37.82% and also enhanced the failure mechanism from sudden/brittle to a gradual ductile failure. The strength of rectangular samples decreases by about 4.95% − 6.52% and deformation increases by 19.52% − 26.46% respectively when compared with square samples. The maximum compressive and shear strength was recorded with cement stabilized 4-steel coir reinforced rammed earth (CS4SCRRE) samples and the maximum deformation was observed with cement stabilized 4-bamboo coir reinforced rammed earth (CS4BCRRE) samples. Prediction model has been developed and validated with respect to theoretical and experimental values. Strong correlations exist between the predicted and experimental values and found suitable for predicting compressive strength and deformation of wallettes.

Bamboo stick diameter, volume and aspect ratios effect on the compressive behavior of bamboo sticks reinforced concrete mixed with sea sand and seawater

Over the past decade, bamboo has received much attention due to its sustainability and strength. The advantages of bamboo over other natural fibres include its abundant existence, high yield, and the ability to quickly reach a maximum height and strength in 3–8 years. Bamboo can be used as an independent structural material and concrete reinforcement in the forms of bamboo culms, bamboo splints, and bamboo composite bars for low-rise and low-cost buildings. In this study, bamboo sticks were adopted as reinforcement for concrete cubes. The following influencing factors were considered: bamboo stick volume ratios of 0.6 %, 1.2 %, and 2.4 %, bamboo stick diameters of 1 mm, 1.5 mm, and 2 mm, and bamboo stick aspect ratios of 10, 20, and 30. The test result shows that with the addition of 0.6 % of sticks, the BSRC compressive strength rose by 3.24 and 17.33 % for length-to-diameter ratios 20 and 30, respectively. The compressive strength of specimens was enhanced by adding 1.2 % and 2.4 % bamboo sticks with a length-to-diameter ratio of 10 by 21.38 and 20.94 %, respectively. The obtained results were compared with the mechanical properties of conventional concrete cubes. Currently, river sand and fresh water are the most often used materials in manufacturing concrete. The widespread use of river sand and freshwater has resulted in major environmental issues. Because many places of the world lack appropriate supplies of fresh water, overuse of this resource is not advised. As a result, saltwater and sea sand were used to create both bamboo stick reinforced concrete and plain concrete specimens. Lastly, a model of strength and stress–strain was proposed.

Flexural behavior of hollow interlocking compressed stabilized earth-block masonry walls under out-of-plane loading

The present study aims to investigate the out-of-plane flexural behavior of hollow interlocking compressed stabilized earth block (ICSEB) masonry walls reinforced with bamboo and steel bars. The effect of grouting, channel block and reinforcement layout (vertical and mesh type) was assessed. A total of thirty masonry walls were fabricated using fibre reinforced blocks and categorized into five groups: two groups of ungrouted and grouted (without bamboo or steel reinforcement) masonry wall specimens and three groups of grouted masonry wall specimens reinforced with bamboo splints and steel bars. All the specimens were subjected to a constant pre-compression load while lateral load parallel to bed joints was gradually applied until failure. In addition, the experimental moment capacity of reinforced masonry walls was compared with the MSJC-11 formulations to assess the applicability. A statistical regression analysis was then performed on the test results to predict the ultimate moment and deformation capacity of all wall specimens. Test results suggest that grout alone has significantly contributed to the load carrying capacity of wall specimens but with a marginal improvement in deformability. While, channel blocks has no significant effect on load carrying capacity of reinforced grouted masonry wall specimens. Bamboo splints and steel bars as internal reinforcements are very effective in preventing the sudden failure and also enhancing the flexural resistance of masonry walls. Steel mesh showed the highest load carrying capacity, lateral deformation and energy absorption capacity. The addition of bamboo or steel reinforcement combined with grout improved the ultimate load carrying, deformation capacity and energy absorption of walls by 114.88%–260.55%, 19%–35.52% and 168.25%–489.28% respectively.The MSJC-11 code overestimated the moment capacity of reinforced masonry walls; whereas the regression models developed accurately predicted the moment capacity and lateral deformation of the masonry walls.

Study on Twining Technologies Adopted by Bamboo Sutra Wrappers of the Tang Dynasty

Bamboo sutra wrapper is made of bamboo splints fastened together with silk threads using the warp twining method. Bamboo sutra wrappers dating to the Tang and Song dynasties are mainly found in Cave 17. They are usually in a rectangular shape with the geometrical, dotted or floral pattern which are quite favored in the Tang dynasty. Affected by Buddhism, sutra wrappers of this kind have also been found in other Asian countries such as Japan and Korea, with a similarity in structure, dimension and twining method.

Strength of two-way Semantan Bamboo reinforced concrete slabs

Steel has been widely known as the essential material for reinforcement. However, many researches have been conducted in order to find an alternative sustainable material to replace steel. In this study, bamboo has been chosen to replace steel as reinforcement is introduced as one of the alternative material for reinforcement of concrete. The Semantan Bamboo (Gigantochloa Scortechinii) splint with a size of 20 mm x 10 mm (Thickness) was used as the main reinforcement. Three samples of two-way concrete slabs were prepared with a dimension of 1200 mm x 1200 mm x 100 mm. One sample will be constructed without reinforcement, while the remaining two samples will be reinforced with 1.5%, 2.5%, 3.5% and 4.5% of bamboo. All the samples will undergo concentrated punch loads and control slab without reinforcement. The results show that the maximum punching shears that the slabs can sustain more 60 kN. The slabs fail by the cracking of concrete at the bottom of the slab under the concentrated load.

Influence of Sisal Fibers on the Properties of Rammed Earth

The use of rammed earth has been increasing widely during recent years in many countries as an alternative material for building houses due to its valuable characteristics such as affordability, environment friendly, comfort, strength and durability. This thesis presents the result of an experimental study to evaluate the compressive strength and bond strength properties of untreated, treated bamboo splints and steel reinforced cement stabilized rammed earth blocks. To overcome the deficiencies of blocks, sisal fibers are added to improve the performance of CSRE blocks. Fibers are secondary reinforced materials and acts as crack arresters which improves the strength of cement stabilized rammed earth blocks. In this experimental study, red soil is mixed by adding four different percentages (5%, 10%, 15%, and 20%) of OPC and sisal fiber with 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% by weight of soil respectively. The bamboo splints were treated by soaking them in chemical solution of boric acid, Copper -Sulphate and Potassium Di-chromate (1.5:3:4).The resin-based adhesive with coarse sand will be applied to the top of bamboo splints. After 28days of curing period the cubes were tested for compressive strength, pull-out test is done for a series of CSRE blocks in which Bamboo splints and steel bars are embedded to find out its bond strength.

Análisis de vigas de hormigón con refuerzo adicional a la armadura de talas de bambú

The aim of this paper is to evaluate, through bending tests, the structural behavior of reinforced concrete beams additionally reinforced by bamboo splints. The bamboo splints are prepared from the stems of the Bambusa vulgaris species. To examine the strength of adhesion between the bamboo splint and concrete, pull out tests are performed for the specimens. The results of the pullout tests of the test samples show the strengthening of the nodes leading to an increase of the normal tension and rupture of splint and not its slip. According to the results of the bending beams, the presence of bamboo splints increases their load capacity when compared with the reference beams. This is indicative of a reduction in the amount of steel required as the structural element. The insertion of the bamboo splints in the beams provides a better performance in terms of the deflection and also leads to a slight increase in the load capacity of the beams. It is worth mentioning that the beams additionally reinforced by bamboo splints exhibit the same pattern of cracking as for reference beams

Structural behavior of reinforced concrete beams strengthened with bamboo splints

The aim of this paper is to evaluate through bending tests the structural behavior of reinforced concrete beams additionally reinforced with bamboo splints coated with rubber latex. The bamboo splints are prepared from the stems of the Bambusa vulgaris species and are reinforced in the nodal regions. To examine the strength of adhesion between the bamboo splint and concrete, pull out tests are performed for the specimens. The results of the pullout tests of the test samples show the strengthening of the nodes leading to an increase in the normal tension and rupture of the splint instead of its slip. According to the results of the bending beams, the presence of bamboo splints increases their load capacity when compared with the reference beams. This fact indicates a reduction in the amount of steel required as the structural element. Strengthening the nodes of the bamboo splints provides better performance in terms of deflection and also leads to a slight increase in the beams load capacity. It is worth mentioning that the beams additionally reinforced with bamboo splints reinforced in the nodal region present the same cracking pattern as that of reference beams.

Technological properties of particleboards produced using mixture of pines and bamboo

ABSTRACT: This paper aimed to evaluate the technological properties of particleboards produced with particles of unconventional species, bamboo of the species Phyllostachys edulis, and of the genus traditionally used by the sector for the production of the particulate panels in Brazil, Pinus spp.The bamboo splints of 3 years old were collected in Frei Rogério, Santa Catarina, being transformed into particles in a mill hammer, while the particles of Pinus spp. were collected from the industrial process of MDP production in Bonet Madeiras e Papéis Ltda Company in Santa Cecília, Santa Catarina. The company used eight-year-old logs of P. taeda and P. elliottii from the thinning process, without distinction of the species. The experiment was composed of five compositions with mixing the bamboo and wood particles in different proportions ((T1)100:0%; (T2)75:25%; (T3)50:50%; (T4)25:75%; (T5)0:100%). The panels were produced nominal density of 700 kg / m³ and pressing cycle of 160ºC and 40 kgf/cm² for 8 minutes. Results reporting physical and mechanical properties of panels were evaluated through Analysis of Variance and Tukey´s Test at 95% probability. The results evidenced that bamboo particles presented potential for the production of particleboard. The most promising results were presented with the addition of 50% of bamboo in the panel composition (T3), mainly by means observed for dimensional stability, as for strength and stiffness. Values of internal bond presented significantly lower averages with the addition of more than 25% of bamboo.

Strength and behaviour of bamboo reinforced concrete wall panels under two way in-plane action

An experimental investigation has been carried out on the use of an environmentally sustainable material, bamboo, in the construction of precast concrete structural wall panels. The strength and behaviour of three prototype bamboo reinforced concrete wall panel specimens under two-way in-plane action was studied. The specimens with varying aspect ratio and thinness ratio were tested to fail under a uniformly distributed in-plane load applied at an eccentricity of t/6. The aspect ratio of the specimens considered includes 1.667, 1.818 and 2 and the thinness ratio includes 12.5, 13.75 and 15. The influence of aspect ratio and thinness ratio of bamboo reinforced concrete wall panels, on its strength and behaviour was discussed. Varnished and sand blasted bamboo splints of 20 mm width and thickness varying from 8 to 15 mm were used as reinforcement in concrete. Based on the study, an empirical equation was developed considering the geometrical parameters of bamboo reinforced concrete wall panels for predicting its ultimate strength under two way in-plane action.

Effect of protection against hot climate on growth performance, physiological response and endocrine profile of growing lambs under semi-arid tropical environment.

In the hot semi-arid tropical region, extreme summer is a major constraint in sheep production. The growth performance of growing lambs is impaired during the summer. Therefore, the present study was conducted to assess the effect of protection against hot climate on growth performance, physiological response, and endocrine profile of growing lambs under semi-arid tropical environment. All the data in the experiment were presented as mean±SE. Thirty Malpura lambs with the age of 122.7±6.05days and body weight of 19.52±0.42kg were allotted into three groups, viz. G1 (control, lambs kept in open area under tree shade), G2 (lambs kept in conventional asbestos-roofed shed), and G3 (lambs kept in designed shed). The allotment was based on their initial body weight so that the mean body weight of each group was similar. In all three types of protection, lambs were provided with sufficient space to move and social interaction. In asbestos-roofed shed (G2), all the four sides from ground to the roof were fenced with strong galvanized iron chain link. But in G3, all the four sides were constructed in a manner that there was 0.13m air space between inner and outer solid brick columns of the wall up to 1.37m height, and rest up to the roof was fenced with bamboo splint net. The air space between the two columns of the wall was filled with sand, and it was kept in moist condition by continuous water drips which provide extra evaporative cooling. The designed shed was basically constructed with bamboo. Tree shade was assured under the natural shades of large trees. The shaded area was protected by wire fences. The experiment was conducted for 45days during very high temperature (May-June). The lambs were provided with ad libitum green fodder, dry roughage, 300g concentrate, and ad libitum drinking water. The respiration rate at morning and afternoon, pulse rate at morning and afternoon and rectal temperature at afternoon was significantly (P<0.05) lower in lambs of G3 as compared to other groups. The final body weight did not differ significantly between the groups, but average daily gain (g/day) was higher in G3 (150.06±11.13) as compared to the G1 (109.69±18.10). The feed conversion rate (FCR) was significantly (P<0.05) better in G3 (5.49±0.08) as compared to G1 (7.65±0.08) and G2 (6.60±0.08). The hemoglobin level was significantly (P<0.05) higher in G1. The endocrine profile did not vary significantly (P>0.05) among the groups, but insulin-like growth factor-1 (IGF-1) was higher in G3. It can be concluded from this study the lambs provided with better protection during summer remained in more comfortable condition, showed better FCR, and although not statistically significant showed better growth performance.

Corrugated bamboo as reinforcement in concrete

This study investigated improving bamboo–concrete bond by increasing mechanical interlock. Pull-out tests were used to measure the bond between bamboo and concrete. Corrugated and non-corrugated bamboo splints were tested, with four different patterns of corrugation. The effectiveness of using linseed oil for waterproofing corrugated and non-corrugated bamboo splints was also investigated. The bond stress and slip at the loaded and free ends were measured and recorded. The results show that the bamboo–concrete bond can be improved with the use of waterproofed corrugated bamboo splints. The bond achieved using waterproofed corrugated bamboo splints was comparable to the bond achieved using splints treated with expensive epoxy treatments. Although certain patterns were found to be more effective in achieving a strong bond with concrete, all the corrugation patterns with 2 mm projections achieved better results in comparison with non-corrugated splints. Linseed oil was found to be effective in improving the bond between corrugated splints and concrete.

Use of Wire Suture for the Management of Fractures in Calves

Various reduction and fixation techniques have been introduced for the treatment of different types of fractures. Therefore, this study was planned to evaluate two methods of fracture treatments in calves having complete fractures due to automobile accident. In addition, a retrospective study was done to observe the occurrence of fractures in calves. Calves presented with the history of automobile accident and clinical signs suggestive of fractures were subjected to detailed physical, orthopaedic and radiographic examination to confirm fractures. For treatment 20 fractures case were included, where 8 cases were treated with closed reduction with external fixation using bamboo splints and plaster of paris. Whereas, open reduction with internal fixation using stainless steel orthopaedic wires and modified thomas splints were used to treat 12 fractures in long bones of calves aged 8 days to 5 months.All calves treated with open reduction and internal fixation showed good weight bearing in the immediate post-operative period. The fixators applied to different bones were well-tolerated, and the animals could lie down, stand and walk freely with the fixator without any problems after 60 days. Post operative radiography confirmed that bone fragments were well maintained until healing occurred and radiograph showed negligible callus and a radioluscent line (less remarkeble radiolucent area) at 60 days. There was no periosteal reaction around the wire suture at the fracture site. So, wire suture provided good alignment and stabilization of fracture fragments, rapid union of fracture resulting in early functional usage of limb. In contrast, two calves cured among 8 calves treated with closed reduction and external fixation, this study resulted that prognosis was not favorable in calves The results of this study exemplify the successful use of wire sutures in the treatment of complete fractures of the long bones in calves.

Bond behaviour of bamboo splints in cement-stabilised rammed earth blocks

This paper represents an effort to study the bond characteristics of plain and noded bamboo splints embedded in cement-stabilised rammed earth (CSRE) blocks. A series of CSRE pullout test specimens and two species of bamboo, namely Melocanna Baccifera and Bambusa Balcooa having an average tensile strength of 384 and 310 MPa, respectively, were fabricated using 4–10% Portland cement. These bamboo species are commonly available and widely used for construction in the north-eastern part of India. Besides considering the effects of soil strength, cement content, splint size and type on bond force and slip, the effect of embedded area was also briefly considered as part of the test programme. The test result showed that pullout bond resistance is correlated to rammed earth compressive strength, splint size and type, and embedded area.

Study on Different Substrates in Stable Surface Flow Wetland

This paper discussed the feasibility and advantage of the removal efficiency of low concentration sewage using three Stable Surface Flow Wetlands (SSFW) with bamboo splint and palm silk as substrates. Under the same hydraulic loading, the result of experiment indicated that the removal rate of COD,TP, TN were 73.97%, 61.42%, 28.98% respectively in SSFW with a bamboo splint substrate, and the corresponding removal rate of SSFW with a palm silk substrate were 78.37%, 69.42%, 24.4%; while substrate without a bamboo splint and a palm silk were 66.61%, 58.71%, 22.23%. The above information demonstrates that the removal efficiency of TN with a bamboo splint is better while the removal efficiency of COD and TP with palm silk is better. Bamboo splint and palm silk have their own advantages when they are applied to SSFW as substrate, which provide theoretical basis for the selection and matching of substrate.

Comportamento estrutural de vigas de concreto reforçadas com ripas de bambu cravejadas de pinos

Uma das deficiências do bambu reforçando vigas de concreto armado está relacionada com deslocamentos relativos entre os dois materiais. A investigação aqui reportada teve como objetivo avaliar experimentalmente a possibilidade de se melhorar o trabalho conjunto bambu-concreto, através do cravejamento de pinos nas ripas de bambu usadas como reforço. Para tanto, oito vigas de concreto foram ensaiadas, das quais seis foram reforçadas com ripas de bambu Dendrocalamus giganteus Munro cravejadas de pinos e duas armadas com ripas de bambu sem a presença dos pinos, como referência. Usaram-se dois tipos de pino: de aço ou de bambu, em número de dois, três ou quatro pinos entre nós. Curvas força-deslocamento e força-deformação dos materiais são apresentadas e discutidas, em que os resultados mostraram que a cravação dos pinos produziu um aumento de rigidez das vigas; contudo, o furo feito para colocação do pino reduziu localmente a seção transversal da ripa de bambu e, consequentemente, a resistência última das vigas. Finalmente, resultados similares foram obtidos em vigas reforçadas com pino de aço ou de bambu.