08021-012 Sands Timber Final Report

Sands Timber Lake is a 60 acre man made impoundment near Blockton, Iowa. The lake is the centerpiece of a 235 acre park, which is owned and managed by the Taylor County Conservation Board. The park is equipped with modern campsites, hiking trails, picnic areas, and a playground. Bordering the western shoreline of the lake is a beautiful hardwood timber which inspired the parks name. Sands Timber Lake has a 4,100 acre drainage area comprised of timber, grassland, and row crop. The lake is fed by four large classic gullies which branch off into many smaller gullies dissecting the drainage area. Since construction in 1993, Sands Timber Lake has been an extremely poor fishery. In 2006 Sands Timber Lake was added to the EPA’s 303d list of impaired water bodies. Turbid water was identified as the primary stressor. In 2007 a bathometric map was made which depicts lake-bottom contours and elevations which, when compared to the original survey of the area, revealed an alarming amount of siltation. What was once a twenty-three foot deep lake in 1994 has now been reduced to a mere fourteen feet. In addition to depth being lost, the lake’s surface has been reduced by nearly ten acres, destroying vital fish habitats. Local interest in preserving and enhancing the lake has led to the completion of a thorough watershed assessment and treatment plan. Included in the plan are several elements, the first being upland treatment. Locals are insistent that if conservation is not implemented in the watershed the lake will continue to degrade and park usage will continue to decline.

Timber Abutment Piling and Back Wall Rehabilitation and Repair, TR-616, 2012

Based on previous National Bridge Inventory data, the state of Iowa has nearly 20,000 bridges on low-volume roads (LVRs). Thus, these bridges are the responsibility of the county engineers. Of the bridges on the county roads, 24 percent are structurally deficient and 5 percent are functionally obsolete. A large number of the older bridges on the LVRs are built on timber piling with timber back walls. In many cases, as timber abutments and piers age, the piling and back wall planks deteriorate at a rate faster than the bridge superstructure. As a result, a large percentage of the structurally deficient bridges on LVRs are classified as such because of the condition of the timber substructure elements. As funds for replacing bridges decline and construction costs increase, effective rehabilitation and strengthening techniques for extending the life of the timber substructures in bridges with structurally sound superstructures has become even more important. Several counties have implemented various techniques to strengthen/repair damaged piling, however, there is minimal data documenting the effectiveness of these techniques. There are numerous instances where cracked and failed pilings have been repaired. However, there are no experimental data on the effectiveness of the repairs or on the percentage of load transferred from the superstructure to the sound pile below. To address the research needs, a review and evaluation of current maintenance and rehabilitation methods was completed. Additionally, a nationwide survey was conducted to learn the methods used beyond Iowa. Field investigation and live-load testing of bridges with certain Iowa methods was completed. Lastly, laboratory testing of new strengthening and rehabilitation methods was performed.

Modeling carbon sequestration and timber production in a regional case study

Abstract

Evaluation of the multicriteria approval method for timber-harvesting group decision support

Abstract

Evaluation of the surface erosion from different timber yarding methods in Honduras

Surface runoff and sediment production from different timber yarding practices, some using Best Management Practices (BMPs) recommended for Honduras, were monitored in experimental plots during the rainy seasons of two consecutive years in pine forest highlands of central Honduras. Different timber yarding systems were applied to pseudo-replicated plots during the rainy seasons of 1999 and 2000. In 1999, two treatments were studied: tractor yarding and skyline cable (a recommended BMP). In 2000, four treatments were evaluated: tractor skidding, skyline cable, animal skidding (another recommended BMP), and undisturbed forest (reference). During the rainy seasons of these years, surface runoff volumes and sediment yield were measured at five 1.5m x 10m erosion plots in each treated area. The results showed significant differences between traditional tractor yarding and the recommended skyline cable and animal skidding methods. Tractor yarding produced six to ten times more erosion during the rainy seasons than cable and animal yarding. The improved soil retention of cable and animal yarding was especially important during September when the highest rainfall occurred in this climate.

Numerical evaluation of the modulus of longitudinal elasticity in structural round timber elements of the Eucalyptus genus

Currently, the standards that deal with the determination of the properties of rigidity and strength for structural round timber elements do not take in consideration in their calculations and mathematical models the influence of the existing irregularities in the geometry of these elements. This study has as objective to determine the effective value of the modulus of longitudinal elasticity for structural round timber pieces of the Eucalyptus citriodora genus by a technique of optimization allied to the Inverse Analysis Method, to the Finite Element Method and the Least Square Method.

The position effect of structural Eucalyptus round timber on the flexural modulus of elasticity

Round timber has great use in civil construction, performing the function of beams, columns, foundations, poles for power distribution among others, with the advantage of not being processed, such as lumber. The structural design of round timber requires determining the elastic properties, mainly the modulus of elasticity. The Brazilian standards responsible for the stiffness and strength determination of round timber are in effect for over twenty years with no technical review. Round timber, for generally present an axis with non-zero curvature according to the position of the element in the bending test, may exhibit different values of modulus of elasticity. This study aims to analyze the position effect of Eucalyptus grandis round timber on the flexural modulus of elasticity. The three-point bending test was evaluated in two different positions based on the longitudinal rotation of the round timber element. The results revealed that at least two different positions of the round timber element are desired to obtain significant modulus of elasticity.

Crown timber regulations

Crown timber regulations which include: 2 double-sided printed pages issued by the Department of Crown Lands (2 copies). Included with this are 3 printed slips of paper. 2 of these are Order and Regulations by S. Richards, Commissioner of Crown Lands, dated May 28, 1869 and 1 is a notice of sale of timber berths dated Aug.1, 1872 by Richard Wm. Scott, commissioner, 1869, 1872.