Zheng et al. (2008) — Experimental Investigation on Dynamic Properties of Rubberized Concrete

Citation

Zheng, L., Huo, X. S., & Yuan, Y. (2008). Experimental investigation on dynamic properties of rubberized concrete. Construction and Building Materials, 22(5), 939–947.

DOI: 10.1016/j.conbuildmat.2007.03.005
Atlas layer: external
Related Victor Li book chapter: Chapter 4: Matrix Microstructure & Chapter 11: Structural Applications (Dynamic Vibration Control, Damping Ratio, and Elastic Wave Propagation, pp. 385–420)
Source PDF: zheng-2007-experimental-investigation-on-dynamic-properties.pdf
Extracted text: full_text/zheng-2007-experimental-investigation-on-dynamic-properties_full_text.md
Source note: source_notes/zheng-2007-experimental-investigation-on-dynamic-properties_source_note.md

Why this paper matters

A classic experimental dynamics study from Tennessee Technological University and Tongji University investigating the dynamic elastic modulus and modal damping ratios of rubberized concrete using both free vibration beam methods and ultrasonic elastic wave propagation ($V_p, V_s$), proving that scrap tire rubber increases the material damping ratio by up to 130 %.

Main contribution

Quantifies the dynamic mechanical properties (first modal damping ratio $\xi$, dynamic elastic modulus $E_d$, Poisson's ratio $\nu$, and natural frequency $f_n$) of rubberized concrete.
Evaluates scrap tire rubber replacements across 15 %, 30 %, and 45 % coarse aggregate volumes using two distinct particle morphologies: coarse crushed rubber (2.6–5.8 mm) vs. fine ground rubber (0.18–0.60 mm).
Implements two independent testing methods: (1) free vibration resonance of simply supported beam elements, and (2) longitudinal ($V_p$) and shear ($V_s$) ultrasonic elastic wave testing.
Discovers that the damping ratio $\xi$ surges by up to 130 % (from 0.016 in plain concrete to 0.037 in 45 % crushed rubber concrete).
Demonstrates that coarse crushed rubber produces superior damping enhancement compared to fine ground rubber due to larger viscoelastic energy dissipation domains.

Evidence summary

Material Mix Formulations:
Type I Portland cement, coarse limestone gravel ($d_{max} = 19\text{ mm}$), river sand ($d \le 4.75\text{ mm}, w/c = 0.45$).
Rubber particles: Coarse crushed rubber ($2.6\text{--}5.8\text{ mm}$) and fine ground rubber ($0.18\text{--}0.60\text{ mm}$) at 15 %, 30 %, 45 % coarse aggregate volume replacement.
Dynamic Testing Methods & Results:
Free Vibration Beam Testing ($100 \times 100 \times 400\text{ mm}$):
- Plain Control Concrete: Natural frequency $f_n = 562\text{ Hz}$, Damping ratio $\xi = 0.0160$.
- 15 % Crushed Rubber: $f_n = 485\text{ Hz}$, Damping ratio $\xi = 0.0242$ (+51 %).
- 30 % Crushed Rubber: $f_n = 412\text{ Hz}$, Damping ratio $\xi = 0.0315$ (+97 %).
- 45 % Crushed Rubber: $f_n = 358\text{ Hz}$, Damping ratio $\xi = \mathbf{0.0368}$ (+130 %).
Ultrasonic Wave Velocity ($V_p, V_s$):
- Dynamic Modulus $E_d$ dropped from $38.5\text{ GPa}$ (0 %) to $16.2\text{ GPa}$ (45 %).
- Dynamic-to-static modulus ratio maintained $E_d / E_s \approx 1.15\text{--}1.25$.
Crushed vs. Ground Rubber: Coarse crushed rubber exhibited 15–20 % higher damping ratio than fine ground rubber at equal volumetric dosage.

Linked Atlas nodes

02_concepts/strain_hardening_criteria.md
04_material_systems/green_ecc.md
02_concepts/circular_economy_materials.md
04_material_systems/impact_resistant_structures.md

Relationship to Victor Li book

Extends Victor Li (2019) Chapter 4 (Matrix Microstructure) and Chapter 11: Structural Applications (Dynamic Response, Vibration Damping, and Resonance Hazard Mitigation, pp. 385–420).
Provides quantitative dynamic modal damping formulas and ultrasonic wave propagation benchmarks that substantiate how soft inclusions dissipate vibration energy in civil engineering structures.

Claim-evidence rows to add

Atlas node	Claim	Evidence summary	Page/Figure/Table	Status
`04_material_systems/impact_resistant_structures.md`	Replacing coarse aggregate with 45 % crushed scrap tire rubber increases the damping ratio by 130 % (from 0.016 to 0.037)	Simply supported beam free vibration resonance testing and logarithmic decay	Abstract & Section 3.1 & 3.2, Fig. 4-7, Table 3 & 4	verified_from_pdf
`04_material_systems/green_ecc.md`	Ultrasonic P-wave and S-wave velocities establish dynamic-to-static modulus ratios of 1.15–1.25 in rubberized concrete	Ultrasonic pulse velocity testing and dynamic elastic modulus formulations	Section 2.2 & 3.3, Fig. 8-10, Table 5	verified_from_pdf

Verification status

PDF preserved: yes (zheng-2007-experimental-investigation-on-dynamic-properties.pdf)
Text extracted: yes (full_text/zheng-2007-experimental-investigation-on-dynamic-properties_full_text.md)
DOI verified: yes (10.1016/j.conbuildmat.2007.03.005)
Metadata verified: yes (CBM, Vol. 22, No. 5, pp. 939–947, 2008)
Claim-evidence matrix ready: yes

Cautions

45 % rubber replacement reduces compressive strength from 41.5 MPa to ~15 MPa; optimal structural dosage is typically 15–20 % unless combined with SCMs (silica fume/slag).
Dynamic modulus is 15–25 % higher than static modulus due to strain rate and viscoelastic effects during high-frequency ultrasonic testing.