What Does An Expert Engineering and Construction Witness Do?

What Does An Expert Engineering and Construction Witness Do?

An expert witness can provide critical, educated opinions on evidence. Gavel image courtesy pixabay.com

A judicial expert, professional witness or expert witness is a witness with the skill, experience and education to have specialized knowledge in a particular subject.

An expert witness has necessary scientific or technical expertise that enables them to offer a specialized opinion as evidence in a court of law. The person’s opinion almost always pertains to evidence or facts within their scope of expertise. This is called an expert opinion.

An expert witness may also be asked to deliver expert evidence about facts from their area of knowledge.

The legal basis for expert witness testimony comes from Scots Law, Davie v Magistrates of Edinburgh (1953). It states that where an expert witness has specialized skills or knowledge in a subject being examined by the court, and that person has been called to court to elaborate on that area for the court, the witness may give evidence of his opinion on their area of expertise. Continue reading

Weather Watch: El Niño And Slope Stability

Weather Watch: El Niño And Slope Stability

Hurricane image courtesy pixabay.com

As we get closer to California’s rainy season, which is usually between November and March, meteorologists are warning of a record-breaking El Niño. El Niño is a warm weather pattern that can cause heavy rain in the Pacific Ocean and surrounding land masses, such as the Pacific Rim countries, including portions of the Western United States.

Over the last six months, California has experienced several major rainstorms. While this has been great for our rain-deprived residents, it’s wreaked havoc on the parched landscape created by the state’s record drought.  In fact, the drought has caused the soils to dry out, leading to surface cracks that will fill with rainwater. Continue reading

Keeping Up With HOA Maintenance

HOA Maintenance

HOA Maintenance Image Courtesy Pixabay.com

When you live in a Homeowner’s Association (HOA), you get some great perks, such as an HOA maintenance team. Some associations also boast parks and pools, full-service yard care. The maintenance teams usually keep those facilities in great condition. If you’re not familiar with how these associations can afford offer these benefits, they typically collect a monthly fee from all residents within the association. Usually agreement to pay these fees is a prerequisite to purchasing a home within the association’s communities.

HOA’s often include homes or condominiums in their communities. We’ve recently been working with condo-based associations that are having difficulties with keeping up their HOA maintenance programs. Continue reading

Stabilizing Seawalls

Stabilizing Seawalls

Image courtesy Pixabay.com

For those who live on a coastline, the sea can be a beautiful sight to wake up to. But as beautiful as it is, its awesome power can be harsh on manmade structures. Unfortunately, you can’t always see the damage before it is too late. Periodic engineering inspections can prevent many problems.

People have worked tirelessly to keep back the elements of the ocean and improve the safety of homes exposed to it. One of the first lines of defense is the bulkhead, or seawall. The use of seawalls goes back thousands of years. Did you know there were seawalls during the time of Constantine I and Byzantium? Things have come a long way since then.

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Dealing with Damage Due to Wind

Dealing With Damage Due To Wind

Damage due to wind can be extensive. Image courtesy pixabay.com

If you’ve ever been in a windstorm, you know that wind is a powerful force of nature and damage due to wind can be extensive. There are several types of wind events. One type of event, called a Microburst, is a downward burst of air from the base of a thunderstorm. Traveling toward the ground at nearly 60 miles per hour, they can increase speed to nearly 100 miles per hour when they hit the ground – causing extensive damage to buildings and trees.

Microbursts are usually formed when dry air combines with rain within a cloud formation. When the dry air causes the rain to evaporate, the temperature of the air lowers. The cooler air will drop down through the cloud formation, gaining speed as it moves toward the ground. If it falls through an area with a large and steady change in temperature, the cooler air will fall faster as the air around it becomes warmer and less dense near the ground. When the air mass reaches the surface, it travels in all directions at high speeds. Continue reading

Dealing With A Roof Collapse

Aftermath of a roof collapse

Aftermath of a roof collapse – image courtesy of pixabay.com

A roof collapse can be sudden, dangerous, and devastating. Often, excessive loads can be the cause of a collapse. These loads can be weather related, involving things such as heavy snow or pooling rainwater. Another cause may be improper roof repair, such as failure to remove shingles or tiles when re-roofing or repairing leaks.

Roofs are typically designed to support their own weight (consisting of framing members, sheathing, and roofing materials), plus the weight of expected live loads.  Live loads consist of people who might need to walk on the roof to service equipment or to perform roof repairs, and the estimated weight of ponded rain (if the roofs are flat), and accumulated snow (if the building is in a snow area).  Each of these conditions must be considered in the design of the supporting members.  One problem that is particular to flat roofs is the deformation of roofing support members that can cause water to pond on the roof.  Once the water begins to pond, the framing members deflect more, which leads to more ponding, which leads to more deformation.  An unstable condition is created in these roofs that can eventually lead to collapse of the roof. Continue reading

What Happens When A Car Hits Your Property

 

What Happens When A Car Hits Your Property?

What happens when a car hits your property? Image courtesy pixabay.com

A few days ago, I was driving through a neighborhood and I saw a car that had jumped a curb and careened in to a home, knocking out a front window and wall. It’s the kind of vehicle accident that could happen to anyone; cars are big, heavy and easy to lose control of. It reminded me of one of Helfrich-Associates’ current projects. So, what happens when a car hits your property?

Our team was recently called by an insurance company and asked to determine how to temporarily support a building after a vehicle had crashed in to it. Continue reading

Case Study: DoubleTree by Hilton Hotel at Berkeley Marina

Case Study: DoubleTree by Hilton Hotel at Berkeley

The DoubleTree by Hilton Hotel at Berkeley.

This week we’ll be covering our latest case study. In early 2011 Helfrich-Associates was asked to examine a hotel in the city of Berkeley and evaluate the structural integrity of a portion of the hotel.

The DoubleTree by Hilton Hotel at Berkeley Marina is located less than 5 miles from Emeryville and only 20 minutes from Oakland International Airport. The hotel is situated on Berkeley Marina.

The hotel, built in the 1970s, had a building that was suffering from titling due to uneven soil conditions. The building in question, number three (3), was built on a 12-inch thick, reinforced mat foundation that was not sufficient to deal with the settling of soft soils. As a result the building had tilted more than 20 inches. Continue reading

Case Study: Severe Sewer-Main Blockage

Manhole Cover

Image of manhole cover courtesy pixabay.com

Sewage backups – they can be one of the most hazardous things that can happen in a place of business or home. Not only can they cause significant health issues for anyone exposed to the area, but they may also cause thousands of dollars in damage to underground piping and any surrounding areas.

In May, 2014 Helfrich-Associates was called in to assess an insurance claim for sewer damage in The City of Burbank, California. The damage occurred when a sewer-main blockage caused sewage to spill onto a commercial property. Continue reading

Warning: Falling Rocks

Alpine: Photo of Damage

A photograph of the damage from falling rock.

Remember when, at the beginning of the Indiana Jones movie, Raiders of the Lost Ark, the scene where Indy takes a golden statue off of a pedestal and a giant boulder begins to tumble down a ramp, almost crushing our hero? Well, imagine that boulder at the top of a hill near your property. Now imagine it rolling down the hill, except your home or commercial structure isn’t Indiana Jones, and it can’t escape!

Helfrich-Associates recently was invited to help resolve just such a situation in Alpine, California. Continue reading