Loging bridges

Why Loging Bridges Need?

When a plantations company starting the bussines, they preparing the land before plant any tree on it. Block system now commonly used as separating line and have many benefit. This line ussualy formed as access road.

Access road in thousands hectares have so many point crossing the water line. In the begining we use loging bridges as temporary construction. The construction using residual wood from land clearing, so this construction have no material cost. Loging bridges as temporary construction should be replaced by permanent construction like concrete bridges, box culvert or steel bridges before aged 5 years. After 5 years wood conditions would be very weak. The life design of loging bridges match with palm tree that starting to harvest in 3 years. It means that the bridges will handling more load frequently.

The Designs

There are two main part of the bridges :

1) Bridge Foundations

Foundations for loging bridges also using wood. There are two common type of log foundations :

a. Pig Head Foundations

Log formations by set wood in 3 side, front river and 2 side as high as road level. This type of foundations will be strong enough to hold the soil pressure from behind tthe structure, also can reduce the water stream from collapsing the bridge.

b. Wood Pile Foundations

In this type of foundations bridge deck put on some wood pile.


2. Bridge deck

Bridge deck using log put and arranged in horizontal positions together. Soil layer used as finishing touch to binding the log and provide smooth surfaces for truck passes the bridges.



The constructions need excavators. Time to complete this work depend on the length of bridges and depth of the river. One week is a fair average time. You can estimate cost by calculate HM of heavy equipment.



Facility Maintenance and Repairing

Maintenance and Repairing Work

Civil engineer (asistant) in estates have scope of works to maintane and repair facilities like housing, roads, bridges, mill or bulking facility. Whatt is maintenance : works do to keep facility in optimum conditions before its broken.

Whatt is repairing : activity to repair facility after broken and back to initial conditions.

Requirement of Maintenance

Maintenance should do periodically. Budget of maintenance works provided every years based on schedule of maintenance. How to arrange schedule of maintenance?

First we must know design criteria for our facilities. Example : septictank volume 1 m3 will full in 4 years and need to be taken out, wall coating need to repainting after 2 years. So we can also estimate the cost for maintenance.

How about repairing?

Repairing cost seems can not to be estimated. But we actualy can estimate the cost.

Here the example : From our experience data, this year 5% of door lock all housing was broken because of usage. So, next year we can budgeting 5 % cost of door lock. The same way for maintenance access road. If 15% area was sinking in rain season and need to fill by stone again we must budgeting for next year. Even we try to put all the risk for repairing, we can not address all. The important think is, every time you have broken facilities you must make report form and asking the money for repairing.

Who is Responsible?

Facility User is responsible for any deffect in their facilities. User must report the list of broken facilities and what need to repair send to civil asistant to verivy. After verivied, additional budget cost can be approved by General affair.