Flexural experiments on prestressed glued bamboo and lumber beam for material selection

Flexural experiments on prestressed glued bamboo and lumber beam for material selection

Nan GuoHaotian Wang Hongliang Zuo

Northeast Forestry University, School of Civil Engineering, Harbin 150040, China

Corresponding Author Email: 
| |
30 June 2018
| Citation



This paper attempts to lay down a material selection criterion for prestressed glued bamboo and lumber (GB&L) beam and other components using bamboo-lumber composite as the main compression member. Through flexural experiments on nine prestressed GB&L beams, the author explored the effects of material type and composite pattern on flexural behaviours, and analysed the performance indices like ultimate bearing capacity and ultimate displacement. The main conclusions are as follows: The typical failure mode of the GB&L beam includes the compressive buckling failure atop the beam at the trisection points, the tensile failure at the bottom, and the horizontal tearing failure. The ultimate load of bamboo and lumber beam was 36%~56% higher than that of poplar beam. Among the GB&L beams, the alternatively arranged section specimen enjoyed the best strength, the compression strain atop the beam fell between 8,000 and 16,000, and the tensile strain at the bottom ranged from 4,000 to 12,000. The strains were much better than those of glued lumber beams, and comparable to those of reconsolidated bamboo beams. Throughout the loading process, the compressive zone was always larger than the tensile zone, and the compressive strain was more obvious than the tensile strain, indicating the full utilization of compressive strength in GB&L beams. The findings of this paper lay the basis for the material selection of prestressed GB&L beam and other compressive components.


prestressed glued bamboo and lumber (GB&L) beam, flexural experiment, ultimate load, failure pattern

1. Introduction
2. Experiment overview
3. Analysis of failure mode and failure mechanism
4. Results and analysis
5. Conclusions

This paper is supported by the Fundamental Research Funds for the Central Universities (Grant No.: 2572017DB02), the Post-Doctoral Scientific Research and Development Fund of Heilongjiang Province in 2016 (Grant No.: LBH-Q16011), and the Science and Technology Research Project of State Forestry Administration (Grant No.: 2014-04).


Anshari B., Guan Z. W., Kitamori A., Jung K., Komatsu K. (2011). Structural behaviour of glued laminated timber beams pre-stressed by compressed wood. Construction and Building Materials, Vol. 29, pp. 24-32.

Cao Y., Wu Y. Q. (2008). Evaluation of statistical strength of bamboo fiber and mechanical properties of fiber reinforced green composite. Journal of Central South University of Technology, Vol. 15, No. 1, pp. 564-567. https://doi.org/10.1007/s11771-008-0422-z

Franke S., Franke B., Harte A. M. (2015). Failure modes and reinforcement techniques for timber beams-State of the art. Construction and Building Materials, Vol. 97, No. 3, pp. 2-13. https://doi.org/10.1016/j.conbuildmat.2015.06.021

Guo N., Chen H. H., Zhang P. Y., Zuo H. L. (2016). The research of parallel to the grain compression performance test of laminated glued bamboo-wood composites. Technical Gazetee, Vol. 23, No. 1, pp. 129-135. https://doi.org/10.17559/TV-20160108190015

Guo N., Jiang H. X. (2016). The finite element analysis on short-time flexural behavior of glue-lumber string beam. International Journal of Earth Sciences and Engineering, Vol. 9, No. 2, pp. 743-749.

Guo N., Liu X. X., He T. (2013). The research on methods of glue-lumber compressive properties test. Information Technology Journal, Vol. 22, No. 12, pp. 6646-6650. https://doi.org/10.3923/itj.2013.6646.6650

Hynynen A. (2016). Futurein wood timber construction in boosting local development. European Spatial Research and Policy, Vol. 23, No. 1, pp. 127-139. https://doi.org/10.1515/esrp-2016-0007

Leijten A. J. M., Franke S., Quenneville P., Gupta R. (2012). Bearing strength capacity of continuous supported timber beams unified approach for test methods and structural design codes. Journal of Structural Engineering, Vol. 138, No. 2, pp. 266-272. https://doi.org/10.1061/(asce)st.1943-541x.0000454

Lin C., Yang H. F., Liu W. Q., Lu W. D., Ling Z. B., Hao J. D. (2014). Prestressed glulam beams flexural performance test research. Journal of structural engineers, Vol. 30, No. 1, pp. 160-164.

Liu W. Q., Yang H. F. (2008). Experimental study on flexural behavior of engineered wood beams. Journal of Building Structures, Vol. 29, No. 1, pp. 90-95.

Luca V. D., Marano C. (2012). Prestressed glulam timbers reinforced with steel bars. Construction and Building Materials, Vol. 30, No. 5, pp. 206-217. https://doi.org/10.1016/j.conbuildmat.2011.11.016

Ma X. X., Wang G., Jiang Z. H., Xian Y., Li H. D. (2014). Comparison of bending creep behavior of bamboo-based composites manufactured by two types of stacking secquences. Bioresources, Vol. 9, No. 3, pp. 5461-5472.

Miljanović S., Zlatar M. (2015). Theoretical and experimental research of external prestressed timber beams in variable moisture conditions. Coupled Systems Mechanics, Vol. 4, No. 2, pp. 191-209. https://doi.org/10.12989/csm.2015.4.2.191

Miller J. F., Bulleit W. M. (2011). Analysis of mechanically laminated timber beams using shear keys. Journal of Structural Engineering, Vol. 137, No. 1, pp. 124-132. https://doi.org/10.1061/(ASCE)ST.1943-541X.0000273

Negrão J. H. (2016). Preliminary study on wire prestressing methods for timber pieces reinforcement. Construction and Building Materials, Vol. 102, No. 1, pp. 1093-1100. https://doi.org/10.1016/j.conbuildmat.2014.11.050