by Carl A. Eckelnam Eva Haviarova Huseyin Akcey Department of Forestry and Natural Resource Purdue University United States

Transcription

1 Use of Small Diameter Timber Resources for Light Timber Frame Constructions, Emergency Shelters, Small Industrial Buildings, Furniture and Assorted Wood Products by Carl A. Eckelnam Eva Haviarova Huseyin Akcey Department of Forestry and Natural Resource Purdue University United States

2 Research Outcomes We have shown that low cost, durable furniture and light timber frame buildings can be constructed from essentially waste wood materials using only the simplest manufacturing techniques with round mortise and tenon joint construction Shortages of school furniture and building frames can be eliminated with little environmental impact While promoting rural community development

3 Presentation Outline Available material resources School furniture products development and production Light timber frame building construction and use Alternative connectors and joinery research

4 Small-Diameter Trees Many forest stands worldwide are over-stocked with small-diameter trees They should be selectively thinned More extensive use of existing timber resources would extend supplies, reduce waste and improve the forest health

5 Plantation Thinnings Plantations need to be thinned to optimize tree growth Presently, plantation thinnings have insufficient market value to justify their removal

6 Residue Material from Tree Plantations Large quantities of potentially useful but largely unused wood materials presently exist and are available for conversion into value-added wood products

7 Potential Products Structural applications offer a high-potential value-added market for small-diameter stems Furniture (especially school furniture) is another valuable product, particularly in under-developed countries

8 School Furniture

9 Costa Rica

10 Costa Rica

11 Traditional Joinery - Square Mortise and Tenon Joint Costa Rica

12 New Joinery - Round Mortise and Tenon Joint

13 Round Mortise and Tenon Manufacturing

14 Solid Wood Construction Combination of strong and weak solid wood species Round mortise and tenon joints Shrink and swell jointing method

15 Performance Testing Direct evaluation of the prototype strength and durability Identification of the areas of possible improvement

16 Manufacturing Process Structure Diagram for Chair

17 Manufacturing Process Structure Diagram for Table

18 Process Analysis Material Flow

19 Pilot Study Summary Product Design Finished Product Manufacturing System Delivery

20 Pilot Study Results Costa Rica

21 Production at Institute of Technology Costa Rica Costa Rican workers were trained to understand the principles of new construction

22 Ergonomic Studies and Technology Transfer in C.R. school furniture placed around of the country

23 Success Stories Jamaica

24 Success Stories Uganda The Humble Way (Orphanage)

25 Success Stories Uganda

26 School Furniture Need for Afghanistan School Furniture Graveyards: - A very common sight at Afghan schools - Only year or two old poorly made furniture given to schools by various aid agencies

27 School Furniture Need for Afghanistan ,400 desks and chairs were provided ,600 desks and chairs are needed

28 Light Timber Frame Construction

29 Need for Housing in Developing Countries (Africa)

30 Round Mortise and Tenon Construction Provide simple and straightforward method of constructing building frames Differs essentially only in the geometry compared to rectangular mortise and tenon construction Tenons are efficient load carriers and are highly resistant to cyclic loading in bending Basic strength characteristics and suitability for use in building frame construction was thoroughly studied

31 Horizontal Drill Press A simple low cost horizontal drill press was built to machine tenons

32 Horizontal Drill Press Alternative horizontal drill press was developed in Costa Rica

33 Machining of Members Tenons for the frame are cut with 2, 3, 4-inch diameter by 12-inch deep hole saws produced by a commercial supplier The excess material was removed from around the tenon with a miter saw Mortises were drilled in the members with 2, 3, 4-inch diameter Forstner bits

34 Parts Fabrication Material was first cut to size Tenons were cut on the ends of the members Mortises were drilled into the sides of the members Standardized parts that can be incorporated into modular construction

35 Frame Construction Corner posts, wall studs, and doorpost tenons were inserted into the corresponding sill mortises Joints were pinned to the sills

36 Frame Construction The ridge rafter beam along with the side rafter plates were extended in order to provide the fly rafters needed for an overhang The walls and roof were sheathed with standard grades of plywood

37 Construction Benefits Easy and rapid assembly from a stock of standardized parts Disassembly took 15 min, and re-assembly 40 min Costly connectors are eliminated Basic or no tools are necessary Unskilled labor can be used to erect a frame High resistance to vertical and lateral loading (hurricanes and earthquakes)

38 Test Models Standardized parts can be easily incorporated into modular constructions to serve a wide variety of needs: backyard storage sheds, shelters, farm building, light industrial buildings, multipurpose buildings-- in both developed and under-developed countries

39 Modular Constructions Rangers Huts Costa Rica

40 Modular Constructions Exhibit building

41 Cottage Industry

42 Alternative Connectors and Joinery

43 Joint Strength Tests - Withdrawal Resistance -Bending Resistance - Shear Test

44 Potential Timber Frame Connectors Through-bolt with dowel nut Through-Bolt with Cross Pipe and Nut Construction

45 Through-Bolt with Cross Pipe and Nut Construction Tension Specimens Nut Located Inside of Cross Pipe Avg. strength is 13,570 lbs in for 3-3/4 in-sq Yellow poplar.

46 Through-Bolt with Cross Pipe and Nut Construction Tension Specimens Nut Located on the Outside of the Cross Pipe Avg. strength is 11,250 lbs in for 3-3/4 in-sq Yellow poplar.

47 Through-Bolt with Cross Pipe and Nut Construction Tension Specimens Reinforced with Cross Bolts Avg. strength is 19,270 lbs in for 1-1/4 pipe 3-3/4 in-sq Yellow poplar. Avg. strength is 23,160 lbs in for 1-1/2 pipe 3-3/4 in-sq Yellow poplar.

48 Through-Bolt with Cross Pipe and Nut Construction Tension Specimens Reinforced with Washers Avg. strength is 19,950 lbs in for 3-3/4 in-sq Yellow poplar.

49 Potential Timber Frame Connectors Tension Specimens Reinforced with Pipe Inserts Avg. strength is 22,890 lbs in for 5-1/4 in-sq Yellow poplar.

50 Through-Bolt with Cross Pipe and Nut Construction Round Tension Specimens Reinforced with Hoop (1/4 in Rod) Avg. strength without reinforcement - 7,238 lbs Avg. strength with reinforcement - 17,740 lbs

51 Truss Applications Round mortise and tenon and trough-bolt with cross pipe and nut connections in truss applications

52 Foot Bridges

53 Summary Areas of interest: developing areas of the world, rural community with small businesses opportunities, indigenous habitats Designs attributes: simple, very durable, attractive, low cost, standardized and modular, structurally proven, specifically adapted to the local area, materials and production processes available Building construction products: light timber frames for low cost houses, small schools, farms, and light industrial building Furniture construction products: institutional furniture, household furniture, furniture for special needs, and playgrounds Manufacturing: cottage type industries or advanced factories, using the simplest manufacturing techniques, few tools and limited worker skills, with quality control build in the process Joinery: round mortise and tenon timber frame and furniture joints, low cost through bolt with cross pipe and nut timber frame connectors Technology transfer: developed and ready to be adopted by appropriate agencies, user groups, or individuals

54 Acknowledgments Rado Gazo Henry Quesada Aldo Ramirez Coretti Rafael Serrano Robert Leavitt Yusuf Erdil Scott Bailey Gary Moorehead